@article {2188, title = {Discovery of genomic loci of the human cerebral cortex using genetically informed brain atlases.}, journal = {Science}, volume = {375}, year = {2022}, month = {2022 02 04}, pages = {522-528}, abstract = {

To determine the impact of genetic variants on the brain, we used genetically informed brain atlases in genome-wide association studies of regional cortical surface area and thickness in 39,898 adults and 9136 children. We uncovered 440 genome-wide significant loci in the discovery cohort and 800 from a post hoc combined meta-analysis. Loci in adulthood were largely captured in childhood, showing signatures of negative selection, and were linked to early neurodevelopment and pathways associated with neuropsychiatric risk. Opposing gradations of decreased surface area and increased thickness were associated with common inversion polymorphisms. Inferior frontal regions, encompassing Broca{\textquoteright}s area, which is important for speech, were enriched for human-specific genomic elements. Thus, a mixed genetic landscape of conserved and human-specific features is concordant with brain hierarchy and morphogenetic gradients.

}, keywords = {Adult, Aged, Aged, 80 and over, Cerebral Cortex, Child, Chromatin, Cohort Studies, Female, Gene Ontology, Genetic Association Studies, Genetic Loci, Genetic Variation, Genome, Human, Genome-Wide Association Study, Humans, Magnetic Resonance Imaging, Male, Mental Disorders, Middle Aged, Molecular Sequence Annotation, Multifactorial Inheritance, Polymorphism, Single Nucleotide, Regulatory Sequences, Nucleic Acid}, issn = {1095-9203}, doi = {10.1126/science.abe8457}, author = {Makowski, Carolina and van der Meer, Dennis and Dong, Weixiu and Wang, Hao and Wu, Yan and Zou, Jingjing and Liu, Cin and Rosenthal, Sara B and Hagler, Donald J and Fan, Chun Chieh and Kremen, William S and Andreassen, Ole A and Jernigan, Terry L and Dale, Anders M and Zhang, Kun and Visscher, Peter M and Yang, Jian and Chen, Chi-Hua} } @article {2289, title = {Lessons from the Stories of Women in Neuroscience.}, journal = {J Neurosci}, volume = {42}, year = {2022}, month = {2022 Jun 15}, pages = {4769-4773}, abstract = {

Women have been contributing to the field of neuroscience since its inception, but their accomplishments are often overlooked. Lack of recognition, among other issues, has led to progressively fewer women at each academic stage; although half of neuroscience graduate students are women, women comprise less than one-third of neuroscience faculty, and even fewer full professors. Those who reach this level continue to struggle to get their work recognized. Women from historically excluded backgrounds are even more starkly underrepresented and face added challenges related to racial, ethnic, and other biases. To increase the visibility of women in neuroscience, promote their voices, and learn about their career journeys, we created Stories of Women in Neuroscience (Stories of WiN). Stories of WiN shares the scientific and personal stories of women neuroscientists with diverse backgrounds, identities, research interests, and at various career stages. From \>70 women highlighted thus far, a major theme has emerged: there is not a single archetype of a woman neuroscientist, nor a single path to "success." Yet, through these diverse experiences run common threads, such as the importance of positive early research experiences, managing imposter syndrome, the necessity of work-life balance, and the challenges of fitting into-or resisting-the "scientist mold" within a patriarchal, racialized academic system. These commonalities reveal important considerations for supporting women neuroscientists. Through the lens of women highlighted by Stories of WiN, we explore the similarities among their journeys and detail specific actionable items to help encourage, support, and sustain women in neuroscience.

}, keywords = {Anxiety Disorders, Ethnicity, Female, Humans, Male, Neurosciences, Racial Groups, Self Concept}, issn = {1529-2401}, doi = {10.1523/JNEUROSCI.0536-22.2022}, author = {Sibener, Leslie J and Kirchgessner, Megan A and Steiner, Sheila and Santiago, Chiaki and Cassataro, Daniela and Rossa, Marley and Profaci, Caterina P and Padilla-Coreano, Nancy} } @article {1788, title = {Imaging brain activity during complex social behaviors in Drosophila with Flyception2.}, journal = {Nat Commun}, volume = {11}, year = {2020}, month = {2020 01 30}, pages = {623}, abstract = {

Optical in vivo recordings from freely walking Drosophila are currently possible only for limited behaviors. Here, we expand the range of accessible behaviors with a retroreflective marker-based tracking and ratiometric brain imaging system, permitting brain activity imaging even in copulating male flies. We discover that P1 neurons, active during courtship, are inactive during copulation, whereas GABAergic mAL neurons remain active during copulation, suggesting a countervailing role of mAL in opposing P1 activity during mating.

}, keywords = {Animals, Brain, Copulation, Courtship, Drosophila, Drosophila Proteins, Female, GABAergic Neurons, Male, Neuroimaging, Neurons, Olfactory Cortex, Sexual Behavior, Animal, Social Behavior}, issn = {2041-1723}, doi = {10.1038/s41467-020-14487-7}, author = {Grover, Dhruv and Katsuki, Takeo and Li, Jinfang and Dawkins, Thomas J and Greenspan, Ralph J} } @article {1669, title = {Setd5 haploinsufficiency alters neuronal network connectivity and leads to autistic-like behaviors in mice.}, journal = {Transl Psychiatry}, volume = {9}, year = {2019}, month = {2019 01 17}, pages = {24}, abstract = {

SETD5, a gene linked to intellectual disability (ID) and autism spectrum disorder (ASD), is a member of the SET-domain family and encodes a putative histone methyltransferase (HMT). To date, the mechanism by which SETD5 haploinsufficiency causes ASD/ID remains an unanswered question. Setd5 is the highly conserved mouse homolog, and although the Setd5 null mouse is embryonic lethal, the heterozygote is viable. Morphological tracing and multielectrode array was used on cultured cortical neurons. MRI was conducted of adult mouse brains and immunohistochemistry of juvenile mouse brains. RNA-Seq was used to investigate gene expression in the developing cortex. Behavioral assays were conducted on adult mice. Setd5 cortical neurons displayed significantly reduced synaptic density and neuritic outgrowth in vitro, with corresponding decreases in network activity and synchrony by electrophysiology. A specific subpopulation of fetal Setd5 cortical neurons showed altered gene expression of neurodevelopment-related genes. Setd5 animals manifested several autism-like behaviors, including hyperactivity, cognitive deficit, and altered social interactions. Anatomical differences were observed in Setd5 adult brains, accompanied by a deficit of deep-layer cortical neurons in the developing brain. Our data converge on a picture of abnormal neurodevelopment driven by Setd5 haploinsufficiency, consistent with a highly penetrant risk factor.

}, keywords = {Animals, Autism Spectrum Disorder, Behavior, Animal, Brain, Female, Genetic Predisposition to Disease, Haploinsufficiency, Heterozygote, Magnetic Resonance Imaging, Male, Methyltransferases, Mice, Mice, Knockout, Mutation, Neurons}, issn = {2158-3188}, doi = {10.1038/s41398-018-0344-y}, author = {Moore, Spencer M and Seidman, Jason S and Ellegood, Jacob and Gao, Richard and Savchenko, Alex and Troutman, Ty D and Abe, Yohei and Stender, Josh and Lee, Daehoon and Wang, Sicong and Voytek, Bradley and Lerch, Jason P and Suh, Hoonkyo and Glass, Christopher K and Muotri, Alysson R} } @article {1687, title = {How struggling adult readers use contextual information when comprehending speech: Evidence from event-related potentials.}, journal = {Int J Psychophysiol}, volume = {125}, year = {2018}, month = {2018 03}, pages = {1-9}, abstract = {

We investigated how struggling adult readers make use of sentence context to facilitate word processing when comprehending spoken language, conditions under which print decoding is not a barrier to comprehension. Stimuli were strongly and weakly constraining sentences (as measured by cloze probability), which ended with the most expected word based on those constraints or an unexpected but plausible word. Community-dwelling adults with varying literacy skills listened to continuous speech while their EEG was recorded. Participants, regardless of literacy level, showed N400 effects yoked to the cloze probability of the targets, with larger N400 amplitudes for less expected than more expected words. However, literacy-related differences emerged in an earlier time window of 170-300 ms: higher literacy adults produced a reduced negativity for strongly predictable targets over anterior channels, similar to previously reported effects on the Phonological Mapping Negativity (PMN), whereas low-literacy adults did not. Collectively, these findings suggest that in auditory sentence processing literacy may not notably affect the incremental activation of semantic features, but that comprehenders with underdeveloped literacy skills may be less likely to engage predictive processing. Thus, basic mechanisms of comprehension may be recruited differently as a function of literacy development-even in spoken language.

}, keywords = {Adult, Aged, Brain Mapping, Comprehension, Electroencephalography, Evoked Potentials, Female, Humans, Literacy, Male, Middle Aged, Neuropsychological Tests, Photic Stimulation, Reaction Time, Reading, Speech, Young Adult}, issn = {1872-7697}, doi = {10.1016/j.ijpsycho.2018.01.013}, author = {Ng, Shukhan and Payne, Brennan R and Stine-Morrow, Elizabeth A L and Federmeier, Kara D} } @article {1674, title = {Peripheral inflammation related to lower fMRI activation during a working memory task and resting functional connectivity among older adults: a preliminary study.}, journal = {Int J Geriatr Psychiatry}, volume = {32}, year = {2017}, month = {2017 Mar}, pages = {341-349}, abstract = {

OBJECTIVE: Peripheral inflammation has been associated with adverse effects on cognition and brain structure in late life, a process called {\textquoteright}inflammaging.{\textquoteright} Identifying biomarkers of preclinical cognitive decline is critical in the development of preventative therapies, and peripheral inflammation may be able to serve as an indicator of cognitive decline. However, little is known regarding the relationship between peripheral inflammation and brain structure and function among older adults.

METHODS: Twenty-four older adults (mean age = 78) underwent a functional magnetic resonance imaging (fMRI) resting state functional connectivity scan, and a subset (n = 14) completed the n-Back working memory task in the scanner. All participants completed a blood draw, and inflammation was measured with interleukin 6 (IL-6) and C-Reactive Protein (CRP).

RESULTS: Surprisingly, age was unrelated to measures of inflammation (IL-6, CRP) or brain function (default mode network (DMN) connectivity; working memory performance; blood oxygenation level dependent (BOLD) activation with higher working memory load). However, lower functional connectivity between the left parietal seed and all other DMN regions was associated with higher levels of IL-6 and CRP. Additionally, greater plasma concentration of IL-6 was associated with lower BOLD activation in the left middle frontal gyrus in response to increased working memory load.

CONCLUSIONS: These preliminary findings support the importance of IL-6 and CRP in brain function among older adults. Frontal and parietal regions may be particularly sensitive to the effects of inflammation. Additionally, these findings provide preliminary evidence of inflammatory contributions to level of neural activity, even after accounting for vascular risk factors.

}, keywords = {Aged, Brain Mapping, C-Reactive Protein, Cognition, Cognitive Dysfunction, Female, Frontal Lobe, Humans, Inflammation, Interleukin-6, Magnetic Resonance Imaging, Male, Memory, Short-Term, Parietal Lobe, Rest}, issn = {1099-1166}, doi = {10.1002/gps.4482}, author = {Dev, Sheena I and Moore, Raeanne C and Soontornniyomkij, Benchawanna and Achim, Cristian L and Jeste, Dilip V and Eyler, Lisa T} } @article {123, title = {Delayed intramuscular human neurotrophin-3 improves recovery in adult and elderly rats after stroke.}, journal = {Brain}, volume = {139}, year = {2016}, month = {2016 Jan}, pages = {259-75}, abstract = {

There is an urgent need for a therapy that reverses disability after stroke when initiated in a time frame suitable for the majority of new victims. We show here that intramuscular delivery of neurotrophin-3 (NT3, encoded by NTF3) can induce sensorimotor recovery when treatment is initiated 24 h after stroke. Specifically, in two randomized, blinded preclinical trials, we show improved sensory and locomotor function in adult (6 months) and elderly (18 months) rats treated 24 h following cortical ischaemic stroke with human NT3 delivered using a clinically approved serotype of adeno-associated viral vector (AAV1). Importantly, AAV1-hNT3 was given in a clinically-feasible timeframe using a straightforward, targeted route (injections into disabled forelimb muscles). Magnetic resonance imaging and histology showed that recovery was not due to neuroprotection, as expected given the delayed treatment. Rather, treatment caused corticospinal axons from the less affected hemisphere to sprout in the spinal cord. This treatment is the first gene therapy that reverses disability after stroke when administered intramuscularly in an elderly body. Importantly, phase I and II clinical trials by others show that repeated, peripherally administered high doses of recombinant NT3 are safe and well tolerated in humans with other conditions. This paves the way for NT3 as a therapy for stroke.

}, keywords = {Adenoviridae, Age Factors, Animals, Endothelin-1, Female, Genetic Vectors, Humans, Injections, Intramuscular, Locomotion, Magnetic Resonance Imaging, Microinjections, Muscle, Skeletal, Neuroimaging, Neurotrophin 3, Pyramidal Tracts, Rats, Recovery of Function, Spinal Cord, Stroke, Time Factors}, issn = {1460-2156}, doi = {10.1093/brain/awv341}, author = {Duricki, Denise A and Hutson, Thomas H and Kathe, Claudia and Soleman, Sara and Gonzalez-Carter, Daniel and Petruska, Jeffrey C and Shine, H David and Chen, Qin and Wood, Tobias C and Bernanos, Michel and Cash, Diana and Williams, Steven C R and Gage, Fred H and Moon, Lawrence D F} } @article {1680, title = {Optogenetic manipulation of neural circuits in awake marmosets.}, journal = {J Neurophysiol}, volume = {116}, year = {2016}, month = {2016 09 01}, pages = {1286-94}, abstract = {

Optogenetics has revolutionized the study of functional neuronal circuitry (Boyden ES, Zhang F, Bamberg E, Nagel G, Deisseroth K. Nat Neurosci 8: 1263-1268, 2005; Deisseroth K. Nat Methods 8: 26-29, 2011). Although these techniques have been most successfully implemented in rodent models, they have the potential to be similarly impactful in studies of nonhuman primate brains. Common marmosets (Callithrix jacchus) have recently emerged as a candidate primate model for gene editing, providing a potentially powerful model for studies of neural circuitry and disease in primates. The application of viral transduction methods in marmosets for identifying and manipulating neuronal circuitry is a crucial step in developing this species for neuroscience research. In the present study we developed a novel, chronic method to successfully induce rapid photostimulation in individual cortical neurons transduced by adeno-associated virus to express channelrhodopsin (ChR2) in awake marmosets. We found that large proportions of neurons could be effectively photoactivated following viral transduction and that this procedure could be repeated for several months. These data suggest that techniques for viral transduction and optical manipulation of neuronal populations are suitable for marmosets and can be combined with existing behavioral preparations in the species to elucidate the functional neural circuitry underlying perceptual and cognitive processes.

}, keywords = {Action Potentials, Animals, Bacterial Proteins, Brain, Callithrix, Dependovirus, Female, Genetic Vectors, Luminescent Proteins, Microelectrodes, Models, Animal, Neural Pathways, Neurons, Optogenetics, Photic Stimulation, Rhodopsin, Serogroup, Wakefulness}, issn = {1522-1598}, doi = {10.1152/jn.00197.2016}, author = {MacDougall, Matthew and Nummela, Samuel U and Coop, Shanna and Disney, Anita and Mitchell, Jude F and Miller, Cory T} } @article {1673, title = {Distinct neural correlates of emotional and cognitive empathy in older adults.}, journal = {Psychiatry Res}, volume = {232}, year = {2015}, month = {2015 Apr 30}, pages = {42-50}, abstract = {

Empathy is thought to be a mechanism underlying prosocial behavior across the lifespan, yet little is known about how levels of empathy relate to individual differences in brain functioning among older adults. In this exploratory study, we examined the neural correlates of affective and cognitive empathy in older adults. Thirty older adults (M=79 years) underwent fMRI scanning and neuropsychological testing and completed a test of affective and cognitive empathy. Brain response during processing of cognitive and emotional stimuli was measured by fMRI in a priori and task-related regions and was correlated with levels of empathy. Older adults with higher levels of affective empathy showed more deactivation in the amygdala and insula during a working memory task, whereas those with higher cognitive empathy showed greater insula activation during a response inhibition task. Our preliminary findings suggest that brain systems linked to emotional and social processing respond differently among older adults with more or less affective and cognitive empathy. That these relationships can be seen both during affective and non-emotional tasks of "cold" cognitive abilities suggests that empathy may impact social behavior through both emotional and cognitive mechanisms.

}, keywords = {Affect, Aged, Aged, 80 and over, Aging, Brain, Brain Mapping, Cognition, Emotions, Empathy, Female, Humans, Magnetic Resonance Imaging, Male, Neuropsychological Tests, Social Behavior, Social Perception}, issn = {1872-7123}, doi = {10.1016/j.pscychresns.2014.10.016}, author = {Moore, Raeanne C and Dev, Sheena I and Jeste, Dilip V and Dziobek, Isabel and Eyler, Lisa T} } @article {199, title = {From suffering to caring: a model of differences among older adults in levels of compassion.}, journal = {Int J Geriatr Psychiatry}, volume = {30}, year = {2015}, month = {2015 Feb}, pages = {185-91}, abstract = {

OBJECTIVE: Compassion is an important contributor to pro-social behavior and maintenance of interpersonal relationships, yet little is known about what factors influence compassion in late life. The aim of this study was to test theories about how past and current stressors and emotional functioning, resilience, and demographic indicators of life experiences are related to compassion among older adults.

METHODS: One thousand and six older adults (50-99 years) completed a comprehensive survey including self-report measures of compassion, resilience, past and present stress, and emotional functioning (i.e., stressful life events, perceived stress, and current and prior depression and anxiety), and demographic information. The sample was randomly split, and exploratory and confirmatory regression analyses were conducted testing hypothesized relationships with compassion.

RESULTS: Exploratory stepwise regression analysis (n = 650) indicated that participants who reported higher levels of compassion were more likely to be female, not currently in a married/married-like relationship, reported higher resilience levels, and had experienced more significant life events. Age, income level, past and current mental distress, and interactions between resilience and other predictors were not significantly related to compassion. The associations between greater self-reported compassion and being female, having greater resilience, and having experienced more significant life events were supported by a confirmatory stepwise regression analysis (n = 356).

CONCLUSIONS: Older women report more compassion than older men. Resilience and significant life events, independently, also appear to facilitate a desire to help others, while current stress and past and present emotional functioning are less relevant. Specificity of findings to older adults is not yet known.

}, keywords = {Age Factors, Aged, Aged, 80 and over, Empathy, Female, Humans, Life Change Events, Male, Marital Status, Middle Aged, Regression Analysis, Resilience, Psychological, Sex Factors, Socioeconomic Factors}, issn = {1099-1166}, doi = {10.1002/gps.4123}, author = {Moore, Raeanne C and Martin, A{\textquoteright}verria Sirkin and Kaup, Allison R and Thompson, Wesley K and Peters, Matthew E and Jeste, Dilip V and Golshan, Shahrokh and Eyler, Lisa T} } @article {1682, title = {Mean signal and response time influences on multivoxel signals of contextual retrieval in the medial temporal lobe.}, journal = {Brain Behav}, volume = {5}, year = {2015}, month = {2015 Feb}, pages = {e00302}, abstract = {

INTRODUCTION: The medial temporal lobe supports integrating the "what," "where," and "when" of an experience into a unified memory. However, it remains unclear how representations of these contextual features are neurally encoded and distributed across medial temporal lobe subregions.

METHODS: This study conducted functional magnetic resonance imaging of the medial temporal lobe, while participants retrieved pair, spatial, and temporal source memories. Multivoxel classifiers were trained to distinguish between retrieval conditions before and after correction for mean signal and response times, to more thoroughly characterize the multivoxel signal associated with memory context.

RESULTS: Activity in perirhinal and parahippocampal cortex dissociated between memory for associated items and memory for their spatiotemporal context, and hippocampal activity was linked to memory for spatial context. However, perirhinal and hippocampal classifiers were, respectively, driven by effects of mean signal amplitude and task difficulty, whereas the parahippocampal classifier survived correction for these effects.

CONCLUSION: These findings demonstrate dissociable coding mechanisms for episodic memory context across the medial temporal lobe, and further highlight a critical distinction between multivoxel representations driven by spatially distributed activity patterns, and those driven by the regional signal.

}, keywords = {Adult, Brain Mapping, Female, Humans, Magnetic Resonance Imaging, Male, Memory, Photic Stimulation, Temporal Lobe, Young Adult}, issn = {2162-3279}, doi = {10.1002/brb3.302}, author = {Reas, Emilie T and Brewer, James B} } @article {126, title = {REST Regulates Non-Cell-Autonomous Neuronal Differentiation and Maturation of Neural Progenitor Cells via Secretogranin II.}, journal = {J Neurosci}, volume = {35}, year = {2015}, month = {2015 Nov 4}, pages = {14872-84}, abstract = {

UNLABELLED: RE-1 silencing transcription factor (REST), a master negative regulator of neuronal differentiation, controls neurogenesis by preventing the differentiation of neural stem cells. Here we focused on the role of REST in the early steps of differentiation and maturation of adult hippocampal progenitors (AHPs). REST knockdown promoted differentiation and affected the maturation of rat AHPs. Surprisingly, REST knockdown cells enhanced the differentiation of neighboring wild-type AHPs, suggesting that REST may play a non-cell-autonomous role. Gene expression analysis identified Secretogranin II (Scg2) as the major secreted REST target responsible for the non-cell-autonomous phenotype. Loss-of-function of Scg2 inhibited differentiation in vitro, and exogenous SCG2 partially rescued this phenotype. Knockdown of REST in neural progenitors in mice led to precocious maturation into neurons at the expense of mushroom spines in vivo. In summary, we found that, in addition to its cell-autonomous function, REST regulates differentiation and maturation of AHPs non-cell-autonomously via SCG2.

SIGNIFICANCE STATEMENT: Our results reveal that REST regulates differentiation and maturation of neural progenitor cells in vitro by orchestrating both cell-intrinsic and non-cell-autonomous factors and that Scg2 is a major secretory target of REST with a differentiation-enhancing activity in a paracrine manner. In vivo, REST depletion causes accelerated differentiation of newborn neurons at the expense of spine defects, suggesting a potential role for REST in the timing of the maturation of granule neurons.

}, keywords = {Animals, Cell Differentiation, Cells, Cultured, Female, Hippocampus, Mice, Mice, Inbred C57BL, Neural Stem Cells, Neurogenesis, Neurons, Rats, Wistar, Repressor Proteins, Secretogranin II}, issn = {1529-2401}, doi = {10.1523/JNEUROSCI.4286-14.2015}, author = {Kim, Hyung Joon and Denli, Ahmet M and Wright, Rebecca and Baul, Tithi D and Clemenson, Gregory D and Morcos, Ari S and Zhao, Chunmei and Schafer, Simon T and Gage, Fred H and Kagalwala, Mohamedi N} } @article {205, title = {Age-related changes in tissue signal properties within cortical areas important for word understanding in 12- to 19-month-old infants.}, journal = {Cereb Cortex}, volume = {24}, year = {2014}, month = {2014 Jul}, pages = {1948-55}, abstract = {

Recently, our laboratory has shown that the neural mechanisms for encoding lexico-semantic information in adults operate functionally by 12-18 months of age within left frontotemporal cortices (Travis et al., 2011. Spatiotemporal neural dynamics of word understanding in 12- to 18-month-old-infants. Cereb Cortex. 8:1832-1839). However, there is minimal knowledge of the structural changes that occur within these and other cortical regions important for language development. To identify regional structural changes taking place during this important period in infant development, we examined age-related changes in tissue signal properties of gray matter (GM) and white matter (WM) intensity and contrast. T1-weighted surface-based measures were acquired from 12- to 19-month-old infants and analyzed using a general linear model. Significant age effects were observed for GM and WM intensity and contrast within bilateral inferior lateral and anterovental temporal regions, dorsomedial frontal, and superior parietal cortices. Region of interest (ROI) analyses revealed that GM and WM intensity and contrast significantly increased with age within the same left lateral temporal regions shown to generate lexico-semantic activity in infants and adults. These findings suggest that neurophysiological processes supporting linguistic and cognitive behaviors may develop before cellular and structural maturation is complete within associative cortices. These results have important implications for understanding the neurobiological mechanisms relating structural to functional brain development.

}, keywords = {Aging, Brain Mapping, Cerebral Cortex, Comprehension, Female, Humans, Image Processing, Computer-Assisted, Infant, Language Development, Magnetic Resonance Imaging, Male, Vocabulary}, issn = {1460-2199}, doi = {10.1093/cercor/bht052}, author = {Travis, Katherine E and Curran, Megan M and Torres, Christina and Leonard, Matthew K and Brown, Timothy T and Dale, Anders M and Elman, Jeffrey L and Halgren, Eric} } @article {203, title = {Gamma band activity and the P3 reflect post-perceptual processes, not visual awareness.}, journal = {Neuroimage}, volume = {101}, year = {2014}, month = {2014 Nov 1}, pages = {337-50}, abstract = {

A primary goal in cognitive neuroscience is to identify neural correlates of conscious perception (NCC). By contrasting conditions in which subjects are aware versus unaware of identical visual stimuli, a number of candidate NCCs have emerged; among them are induced gamma band activity in the EEG and the P3 event-related potential. In most previous studies, however, the critical stimuli were always directly relevant to the subjects{\textquoteright} task, such that aware versus unaware contrasts may well have included differences in post-perceptual processing in addition to differences in conscious perception per se. Here, in a series of EEG experiments, visual awareness and task relevance were manipulated independently. Induced gamma activity and the P3 were absent for task-irrelevant stimuli regardless of whether subjects were aware of such stimuli. For task-relevant stimuli, gamma and the P3 were robust and dissociable, indicating that each reflects distinct post-perceptual processes necessary for carrying-out the task but not for consciously perceiving the stimuli. Overall, this pattern of results challenges a number of previous proposals linking gamma band activity and the P3 to conscious perception.

}, keywords = {Adult, Attention, Awareness, Consciousness, Electroencephalography, Event-Related Potentials, P300, Female, Gamma Rhythm, Humans, Male, Psychomotor Performance, Visual Perception, Young Adult}, issn = {1095-9572}, doi = {10.1016/j.neuroimage.2014.07.024}, author = {Pitts, Michael A and Padwal, Jennifer and Fennelly, Daniel and Mart{\'\i}nez, Ant{\'\i}gona and Hillyard, Steven A} } @article {208, title = {Inhibitory motor control based on complex stopping goals relies on the same brain network as simple stopping.}, journal = {Neuroimage}, volume = {103}, year = {2014}, month = {2014 Dec}, pages = {225-34}, abstract = {

Much research has modeled action-stopping using the stop-signal task (SST), in which an impending response has to be stopped when an explicit stop-signal occurs. A limitation of the SST is that real-world action-stopping rarely involves explicit stop-signals. Instead, the stopping-system engages when environmental features match more complex stopping goals. For example, when stepping into the street, one monitors path, velocity, size, and types of objects and only stops if there is a vehicle approaching. Here, we developed a task in which participants compared the visual features of a multidimensional go-stimulus to a complex stopping-template, and stopped their go-response if all features matched the template. We used independent component analysis of EEG data to show that the same motor inhibition brain network that explains action-stopping in the SST also implements motor inhibition in the complex-stopping task. Furthermore, we found that partial feature overlap between go-stimulus and stopping-template led to motor slowing, which also corresponded with greater stopping-network activity. This shows that the same brain system for action-stopping to explicit stop-signals is recruited to slow or stop behavior when stimuli match a complex stopping goal. The results imply a generalizability of the brain{\textquoteright}s network for simple action-stopping to more ecologically valid scenarios.

}, keywords = {Adolescent, Adult, Brain, Brain Mapping, Electroencephalography, Female, Goals, Humans, Inhibition (Psychology), Male, Psychomotor Performance, Reaction Time, Young Adult}, issn = {1095-9572}, doi = {10.1016/j.neuroimage.2014.09.048}, author = {Wessel, Jan R and Aron, Adam R} } @article {185, title = {Neural language processing in adolescent first-language learners.}, journal = {Cereb Cortex}, volume = {24}, year = {2014}, month = {2014 Oct}, pages = {2772-83}, abstract = {

The relation between the timing of language input and development of neural organization for language processing in adulthood has been difficult to tease apart because language is ubiquitous in the environment of nearly all infants. However, within the congenitally deaf population are individuals who do not experience language until after early childhood. Here, we investigated the neural underpinnings of American Sign Language (ASL) in 2 adolescents who had no sustained language input until they were approximately 14 years old. Using anatomically constrained magnetoencephalography, we found that recently learned signed words mainly activated right superior parietal, anterior occipital, and dorsolateral prefrontal areas in these 2 individuals. This spatiotemporal activity pattern was significantly different from the left fronto-temporal pattern observed in young deaf adults who acquired ASL from birth, and from that of hearing young adults learning ASL as a second language for a similar length of time as the cases. These results provide direct evidence that the timing of language experience over human development affects the organization of neural language processing.

}, keywords = {Adolescent, Adult, Age Factors, Cerebral Cortex, Critical Period (Psychology), Deafness, Female, Functional Laterality, Humans, Language Development, Learning, Magnetoencephalography, Male, Semantics, Sign Language, Young Adult}, issn = {1460-2199}, doi = {10.1093/cercor/bht137}, author = {Ferjan Ramirez, Naja and Leonard, Matthew K and Torres, Christina and Hatrak, Marla and Halgren, Eric and Mayberry, Rachel I} } @article {140, title = {Non-cell-autonomous mechanism of activity-dependent neurotransmitter switching.}, journal = {Neuron}, volume = {82}, year = {2014}, month = {2014 Jun 4}, pages = {1004-16}, abstract = {

Activity-dependent neurotransmitter switching engages genetic programs regulating transmitter synthesis, but the mechanism by which activity is transduced is unknown. We suppressed activity in single neurons in the embryonic spinal cord to determine whether glutamate-gamma-aminobutyric acid (GABA) switching is cell autonomous. Transmitter respecification did not occur, suggesting that it is homeostatically regulated by the level of activity in surrounding neurons. Graded increase in the number of silenced neurons in cultures led to graded decrease in the number of neurons expressing GABA, supporting non-cell-autonomous transmitter switching. We found that brain-derived neurotrophic factor (BDNF) is expressed in the spinal cord during the period of transmitter respecification and that spike activity causes release of BDNF. Activation of TrkB receptors triggers a signaling cascade involving JNK-mediated activation of cJun that regulates tlx3, a glutamate/GABA selector gene, accounting for calcium-spike BDNF-dependent transmitter switching. Our findings identify a molecular mechanism for activity-dependent respecification of neurotransmitter phenotype in developing spinal neurons.

}, keywords = {Animals, Brain-Derived Neurotrophic Factor, Calcium, Cells, Cultured, Female, gamma-Aminobutyric Acid, Glutamic Acid, JNK Mitogen-Activated Protein Kinases, Neurons, Phosphorylation, Proto-Oncogene Proteins c-jun, Signal Transduction, Spinal Cord, Xenopus laevis}, issn = {1097-4199}, doi = {10.1016/j.neuron.2014.04.029}, author = {Guemez-Gamboa, Alicia and Xu, Lin and Meng, Da and Spitzer, Nicholas C} } @article {197, title = {Tool morphology constrains the effects of tool use on body representations.}, journal = {J Exp Psychol Hum Percept Perform}, volume = {40}, year = {2014}, month = {2014 Dec}, pages = {2143-53}, abstract = {

What factors constrain whether tool use modulates the user{\textquoteright}s body representations? To date, studies on representational plasticity following tool use have primarily focused on the act of using the tool. Here, we investigated whether the tool{\textquoteright}s morphology also serves to constrain plasticity. In 2 experiments, we varied whether the tool was morphologically similar to a target body part (Experiment 1, hand; Experiment 2, arm). Participants judged the tactile distance between pairs of points applied to their tool-using target body surface and forehead (control surface) before and after tool use. We applied touch in 2 orientations, allowing us to quantify how tool use modulates the representation{\textquoteright}s shape. Significant representational plasticity in hand shape (increase in width, decrease in length) was found when the tool was morphologically similar to a hand (Experiment 1A), but not when the tool was arm-shaped (Experiment 1B). Conversely, significant representational plasticity was found on the arm when the tool was arm-shaped (Experiment 2B), but not when hand-shaped (Experiment 2A). Taken together, our results indicate that morphological similarity between the tool and the effector constrains tool-induced representational plasticity. The embodiment of tools may thus depend on a match-to-template process between tool morphology and representation of the body.

}, keywords = {Adolescent, Adult, Body Image, Discrimination (Psychology), Distance Perception, Female, Form Perception, Humans, Judgment, Male, Size Perception, Tool Use Behavior, Touch Perception, Young Adult}, issn = {1939-1277}, doi = {10.1037/a0037777}, author = {Miller, Luke E and Longo, Matthew R and Saygin, Ayse P} } @article {200, title = {Contrast dependence and differential contributions from somatostatin- and parvalbumin-expressing neurons to spatial integration in mouse V1.}, journal = {J Neurosci}, volume = {33}, year = {2013}, month = {2013 Jul 3}, pages = {11145-54}, abstract = {

A characteristic feature in the primary visual cortex is that visual responses are suppressed as a stimulus extends beyond the classical receptive field. Here, we examined the role of inhibitory neurons expressing somatostatin (SOM$^{+}$) or parvalbumin (PV$^{+}$) on surround suppression and preferred receptive field size. We recorded multichannel extracellular activity in V1 of transgenic mice expressing channelrhodopsin in SOM$^{+}$ neurons or PV$^{+}$ neurons. Preferred size and surround suppression were measured using drifting square-wave gratings of varying radii and at two contrasts. Consistent with findings in primates, we found that the preferred size was larger for lower contrasts across all cortical depths, whereas the suppression index (SI) showed a trend to decrease with contrast. We then examined the effect of these metrics on units that were suppressed by photoactivation of either SOM$^{+}$ or PV$^{+}$ neurons. When activating SOM$^{+}$ neurons, we found a significant increase in SI at cortical depths \>400 μm, whereas activating PV$^{+}$ neurons caused a trend toward lower SIs regardless of cortical depth. Conversely, activating PV$^{+}$ neurons significantly increased preferred size across all cortical depths, similar to lowering contrast, whereas activating SOM$^{+}$ neurons had no systematic effect on preferred size across all depths. These data suggest that SOM$^{+}$ and PV$^{+}$ neurons contribute differently to spatial integration. Our findings are compatible with the notion that SOM$^{+}$ neurons mediate surround suppression, particularly in deeper cortex, whereas PV$^{+}$ activation decreases the drive of the input to cortex and therefore resembles the effects on spatial integration of lowering contrast.

}, keywords = {Animals, Contrast Sensitivity, Female, Male, Mice, Mice, Transgenic, Neurons, Parvalbumins, Photic Stimulation, Somatostatin, Space Perception, Visual Cortex}, issn = {1529-2401}, doi = {10.1523/JNEUROSCI.5320-12.2013}, author = {Nienborg, Hendrikje and Hasenstaub, Andrea and Nauhaus, Ian and Taniguchi, Hiroki and Huang, Z Josh and Callaway, Edward M} } @article {204, title = {Independence of early speech processing from word meaning.}, journal = {Cereb Cortex}, volume = {23}, year = {2013}, month = {2013 Oct}, pages = {2370-9}, abstract = {

We combined magnetoencephalography (MEG) with magnetic resonance imaging and electrocorticography to separate in anatomy and latency 2 fundamental stages underlying speech comprehension. The first acoustic-phonetic stage is selective for words relative to control stimuli individually matched on acoustic properties. It begins \~{}60 ms after stimulus onset and is localized to middle superior temporal cortex. It was replicated in another experiment, but is strongly dissociated from the response to tones in the same subjects. Within the same task, semantic priming of the same words by a related picture modulates cortical processing in a broader network, but this does not begin until \~{}217 ms. The earlier onset of acoustic-phonetic processing compared with lexico-semantic modulation was significant in each individual subject. The MEG source estimates were confirmed with intracranial local field potential and high gamma power responses acquired in 2 additional subjects performing the same task. These recordings further identified sites within superior temporal cortex that responded only to the acoustic-phonetic contrast at short latencies, or the lexico-semantic at long. The independence of the early acoustic-phonetic response from semantic context suggests a limited role for lexical feedback in early speech perception.

}, keywords = {Adult, Brain, Brain Mapping, Female, Humans, Magnetic Resonance Imaging, Magnetoencephalography, Male, Speech Perception, Young Adult}, issn = {1460-2199}, doi = {10.1093/cercor/bhs228}, author = {Travis, Katherine E and Leonard, Matthew K and Chan, Alexander M and Torres, Christina and Sizemore, Marisa L and Qu, Zhe and Eskandar, Emad and Dale, Anders M and Elman, Jeffrey L and Cash, Sydney S and Halgren, Eric} } @article {181, title = {Atypical social referencing in infant siblings of children with autism spectrum disorders.}, journal = {J Autism Dev Disord}, volume = {42}, year = {2012}, month = {2012 Dec}, pages = {2611-21}, abstract = {

Social referencing was investigated in 18-month-old siblings of children with autism spectrum disorders (ASD; "high-risk infants"). Infants were exposed to novel toys, which were emotionally tagged via adults{\textquoteright} facial and vocal signals. Infants{\textquoteright} information seeking (initiation of joint attention with an adult) and their approach/withdrawal behavior toward the toys before versus after the adults{\textquoteright} emotional signals was measured. Compared to both typically developing infants and high-risk infants without ASD, infants later diagnosed with ASD engaged in slower information seeking, suggesting that this aspect of referencing may be an early indicator of ASD. High-risk infants, both those who were and those who were not later diagnosed with ASD, exhibited impairments in regulating their behavior based on the adults{\textquoteright} emotional signals, suggesting that this aspect of social referencing may reflect an endophenotype for ASD.

}, keywords = {Attention, Child, Child Development, Child Development Disorders, Pervasive, Child, Preschool, Emotions, Endophenotypes, Female, Humans, Infant, Infant Behavior, Male, Risk Factors, Siblings, Social Behavior}, issn = {1573-3432}, doi = {10.1007/s10803-012-1518-8}, author = {Cornew, Lauren and Dobkins, Karen R and Akshoomoff, Natacha and McCleery, Joseph P and Carver, Leslie J} } @article {163, title = {Genes involved in sex pheromone discrimination in Drosophila melanogaster and their background-dependent effect.}, journal = {PLoS One}, volume = {7}, year = {2012}, month = {2012}, pages = {e30799}, abstract = {

Mate choice is based on the comparison of the sensory quality of potential mating partners, and sex pheromones play an important role in this process. In Drosophila melanogaster, contact pheromones differ between male and female in their content and in their effects on male courtship, both inhibitory and stimulatory. To investigate the genetic basis of sex pheromone discrimination, we experimentally selected males showing either a higher or lower ability to discriminate sex pheromones over 20 generations. This experimental selection was carried out in parallel on two different genetic backgrounds: wild-type and desat1 mutant, in which parental males showed high and low sex pheromone discrimination ability respectively. Male perception of male and female pheromones was separately affected during the process of selection. A comparison of transcriptomic activity between high and low discrimination lines revealed genes not only that varied according to the starting genetic background, but varied reciprocally. Mutants in two of these genes, Shaker and quick-to-court, were capable of producing similar effects on discrimination on their own, in some instances mimicking the selected lines, in others not. This suggests that discrimination of sex pheromones depends on genes whose activity is sensitive to genetic context and provides a rare, genetically defined example of the phenomenon known as "allele flips," in which interactions have reciprocal effects on different genetic backgrounds.

}, keywords = {Animals, Animals, Genetically Modified, Behavior, Animal, Breeding, Courtship, Drosophila melanogaster, Female, Genes, Insect, Male, Mutation, Olfactory Perception, Reproduction, Sex Attractants, Sexual Behavior, Animal, Species Specificity}, issn = {1932-6203}, doi = {10.1371/journal.pone.0030799}, author = {Houot, Benjamin and Fraichard, St{\'e}phane and Greenspan, Ralph J and Ferveur, Jean-Fran{\c c}ois} } @article {190, title = {Signed words in the congenitally deaf evoke typical late lexicosemantic responses with no early visual responses in left superior temporal cortex.}, journal = {J Neurosci}, volume = {32}, year = {2012}, month = {2012 Jul 11}, pages = {9700-5}, abstract = {

Congenitally deaf individuals receive little or no auditory input, and when raised by deaf parents, they acquire sign as their native and primary language. We asked two questions regarding how the deaf brain in humans adapts to sensory deprivation: (1) is meaning extracted and integrated from signs using the same classical left hemisphere frontotemporal network used for speech in hearing individuals, and (2) in deafness, is superior temporal cortex encompassing primary and secondary auditory regions reorganized to receive and process visual sensory information at short latencies? Using MEG constrained by individual cortical anatomy obtained with MRI, we examined an early time window associated with sensory processing and a late time window associated with lexicosemantic integration. We found that sign in deaf individuals and speech in hearing individuals activate a highly similar left frontotemporal network (including superior temporal regions surrounding auditory cortex) during lexicosemantic processing, but only speech in hearing individuals activates auditory regions during sensory processing. Thus, neural systems dedicated to processing high-level linguistic information are used for processing language regardless of modality or hearing status, and we do not find evidence for rewiring of afferent connections from visual systems to auditory cortex.

}, keywords = {Adolescent, Adult, Brain Mapping, Deafness, Evoked Potentials, Female, Functional Laterality, Humans, Magnetic Fields, Magnetic Resonance Imaging, Magnetoencephalography, Male, Photic Stimulation, Semantics, Sign Language, Temporal Lobe, Time Factors, Young Adult}, issn = {1529-2401}, doi = {10.1523/JNEUROSCI.1002-12.2012}, author = {Leonard, Matthew K and Ferjan Ramirez, Naja and Torres, Christina and Travis, Katherine E and Hatrak, Marla and Mayberry, Rachel I and Halgren, Eric} } @article {202, title = {Visual processing of contour patterns under conditions of inattentional blindness.}, journal = {J Cogn Neurosci}, volume = {24}, year = {2012}, month = {2012 Feb}, pages = {287-303}, abstract = {

An inattentional blindness paradigm was adapted to measure ERPs elicited by visual contour patterns that were or were not consciously perceived. In the first phase of the experiment, subjects performed an attentionally demanding task while task-irrelevant line segments formed square-shaped patterns or random configurations. After the square patterns had been presented 240 times, subjects{\textquoteright} awareness of these patterns was assessed. More than half of all subjects, when queried, failed to notice the square patterns and were thus considered inattentionally blind during this first phase. In the second phase of the experiment, the task and stimuli were the same, but following this phase, all of the subjects reported having seen the patterns. ERPs recorded over the occipital pole differed in amplitude from 220 to 260 msec for the pattern stimuli compared with the random arrays regardless of whether subjects were aware of the patterns. At subsequent latencies (300-340 msec) however, ERPs over bilateral occipital-parietal areas differed between patterns and random arrays only when subjects were aware of the patterns. Finally, in a third phase of the experiment, subjects viewed the same stimuli, but the task was altered so that the patterns became task relevant. Here, the same two difference components were evident but were followed by a series of additional components that were absent in the first two phases of the experiment. We hypothesize that the ERP difference at 220-260 msec reflects neural activity associated with automatic contour integration whereas the difference at 300-340 msec reflects visual awareness, both of which are dissociable from task-related postperceptual processing.

}, keywords = {Adult, Attention, Awareness, Brain, Brain Mapping, Electroencephalography, Evoked Potentials, Visual, Female, Humans, Male, Perceptual Masking, Photic Stimulation, Reaction Time, Visual Perception}, issn = {1530-8898}, doi = {10.1162/jocn_a_00111}, author = {Pitts, Michael A and Mart{\'\i}nez, Ant{\'\i}gona and Hillyard, Steven A} } @article {207, title = {Hippocampal signals for strong memory when associative memory is available and when it is not.}, journal = {Hippocampus}, volume = {21}, year = {2011}, month = {2011 Jan}, pages = {9-21}, abstract = {

The paired-associate task has been used with functional magnetic resonance imaging (fMRI) in studies that assessed the role of the medial temporal lobe (MTL) subserving recollection and familiarity.Some researchers have interpreted their results to mean that the hippocampus selectively subserves recollection and not familiarity[cf., Eichenbaum et al., (2007) Annu Rev Neurosci 30:123{\textendash}152]. Yet many of these results confound recollection and familiarity with strong and weak memories, and it is not clear whether the conclusions represent differences between memory processes or memory strength. In the current study, participants were scanned with fMRI during retrieval in a paired-associate task, and a new approach separated the analysis of memory strength from the analysis of memory processes. The data were sorted by confidence level in an old/new task, and the high-confidence responses were compared in categories when associative memory was highly accurate and when it was not available. The results show that high-confidence memory produced increased activity in the hippocampus,relative to the level for forgotten pairs, both when associative memory was available and when it was not. Two interpretations are discussed for the behavioral results for when associative memory was not available: one account based on familiarity and the other account based on noncriterial recollection. The conclusion is that recognition of the word-pairs was based on familiarity when associative memory was not available. Together with the fMRI results that activity in two regions associated with cognitive control (left ventrolateral prefrontal cortex and left inferior parietal lobule) was greater when responses were based on associative memory than when based on familiarity, the findings suggest that the hippocampus supports strong memory and that cortical regions make an additional contribution to recollection.

}, keywords = {Brain Mapping, Female, Hippocampus, Humans, Image Processing, Computer-Assisted, Magnetic Resonance Imaging, Male, Memory}, issn = {1098-1063}, doi = {10.1002/hipo.20716}, author = {Wais, Peter E} } @article {192, title = {Language proficiency modulates the recruitment of non-classical language areas in bilinguals.}, journal = {PLoS One}, volume = {6}, year = {2011}, month = {2011}, pages = {e18240}, abstract = {

Bilingualism provides a unique opportunity for understanding the relative roles of proficiency and order of acquisition in determining how the brain represents language. In a previous study, we combined magnetoencephalography (MEG) and magnetic resonance imaging (MRI) to examine the spatiotemporal dynamics of word processing in a group of Spanish-English bilinguals who were more proficient in their native language. We found that from the earliest stages of lexical processing, words in the second language evoke greater activity in bilateral posterior visual regions, while activity to the native language is largely confined to classical left hemisphere fronto-temporal areas. In the present study, we sought to examine whether these effects relate to language proficiency or order of language acquisition by testing Spanish-English bilingual subjects who had become dominant in their second language. Additionally, we wanted to determine whether activity in bilateral visual regions was related to the presentation of written words in our previous study, so we presented subjects with both written and auditory words. We found greater activity for the less proficient native language in bilateral posterior visual regions for both the visual and auditory modalities, which started during the earliest word encoding stages and continued through lexico-semantic processing. In classical left fronto-temporal regions, the two languages evoked similar activity. Therefore, it is the lack of proficiency rather than secondary acquisition order that determines the recruitment of non-classical areas for word processing.

}, keywords = {Adult, Brain Mapping, Female, Humans, Language, Language Development, Magnetic Resonance Imaging, Magnetoencephalography, Male, Multilingualism, Young Adult}, issn = {1932-6203}, doi = {10.1371/journal.pone.0018240}, author = {Leonard, Matthew K and Torres, Christina and Travis, Katherine E and Brown, Timothy T and Hagler, Donald J and Dale, Anders M and Elman, Jeffrey L and Halgren, Eric} } @article {212, title = {Neural substrates of time perception and impulsivity.}, journal = {Brain Res}, volume = {1406}, year = {2011}, month = {2011 Aug 11}, pages = {43-58}, abstract = {

Several studies provide empirical evidence for the association between impulsivity and time perception. However, little is known about the neural substrates underlying this function. This investigation examined the influence of impulsivity on neural activation patterns during the encoding and reproduction of intervals with durations of 3, 9 and 18s using event-related functional magnetic resonance imaging (fMRI). Twenty-seven subjects participated in this study, including 15 high impulsive subjects that were classified based on their self-rating. FMRI activation during the duration reproduction task was correlated with measures of two self-report questionnaires related to the concept of impulsivity (Barratt Impulsiveness Scale, BIS; Zimbardo Time Perspective Inventory, ZTPI). Behaviorally, those individuals who under-reproduced temporal intervals also showed lower scores on the ZTPI future perspective subscale and higher scores on the BIS. FMRI activation revealed an accumulating pattern of neural activity peaking at the end of the 9- and 18-s intervals within right posterior insula. Activations of brain regions during the reproduction phase of the timing task, such as those related to motor execution as well as to the {\textquoteright}core control network{\textquoteright} - encompassing the inferior frontal and medial frontal cortices, the anterior insula as well as the inferior parietal cortex - were significantly correlated with reproduced duration, as well as with BIS and ZTPI subscales. In particular, the greater activation in these regions the shorter were the reproduced intervals, the more impulsive was an individual and the less pronounced the future perspective. Activation in the core control network, thus, may form a biological marker for cognitive time management and for impulsiveness.

}, keywords = {Adolescent, Brain, Brain Mapping, Female, Humans, Image Processing, Computer-Assisted, Impulsive Behavior, Magnetic Resonance Imaging, Male, Neuropsychological Tests, Oxygen, Personality Inventory, Reaction Time, Self Report, Surveys and Questionnaires, Time Factors, Time Perception, Young Adult}, issn = {1872-6240}, doi = {10.1016/j.brainres.2011.06.048}, author = {Wittmann, Marc and Simmons, Alan N and Flagan, Taru and Lane, Scott D and Wackermann, Ji{\v r}{\'\i} and Paulus, Martin P} } @article {206, title = {Spatiotemporal neural dynamics of word understanding in 12- to 18-month-old-infants.}, journal = {Cereb Cortex}, volume = {21}, year = {2011}, month = {2011 Aug}, pages = {1832-9}, abstract = {

Learning words is central in human development. However, lacking clear evidence for how or where language is processed in the developing brain, it is unknown whether these processes are similar in infants and adults. Here, we use magnetoencephalography in combination with high-resolution structural magnetic resonance imaging to noninvasively estimate the spatiotemporal distribution of word-selective brain activity in 12- to 18-month-old infants. Infants watched pictures of common objects and listened to words that they understood. A subset of these infants also listened to familiar words compared with sensory control sounds. In both experiments, words evoked a characteristic event-related brain response peaking \~{}400 ms after word onset, which localized to left frontotemporal cortices. In adults, this activity, termed the N400m, is associated with lexico-semantic encoding. Like adults, we find that the amplitude of the infant N400m is also modulated by semantic priming, being reduced to words preceded by a semantically related picture. These findings suggest that similar left frontotemporal areas are used for encoding lexico-semantic information throughout the life span, from the earliest stages of word learning. Furthermore, this ontogenetic consistency implies that the neurophysiological processes underlying the N400m may be important both for understanding already known words and for learning new words.

}, keywords = {Adult, Brain Mapping, Cerebral Cortex, Evoked Potentials, Auditory, Female, Humans, Infant, Language Tests, Learning, Magnetic Resonance Imaging, Magnetoencephalography, Male, Neurons, Speech Perception, Vocabulary}, issn = {1460-2199}, doi = {10.1093/cercor/bhq259}, author = {Travis, Katherine E and Leonard, Matthew K and Brown, Timothy T and Hagler, Donald J and Curran, Megan and Dale, Anders M and Elman, Jeffrey L and Halgren, Eric} } @article {211, title = {Accumulation of neural activity in the posterior insula encodes the passage of time.}, journal = {Neuropsychologia}, volume = {48}, year = {2010}, month = {2010 Aug}, pages = {3110-20}, abstract = {

A number of studies have examined the perception of time with durations ranging from milliseconds to a few seconds, however the neural basis of these processes are still poorly understood and the neural substrates underlying the perception of multiple-second intervals are unknown. Here we present evidence of neural systems activity in circumscribed areas of the human brain involved in the encoding of intervals with durations of 9 and 18s in a temporal reproduction task using event-related functional magnetic resonance imaging (fMRI). During the encoding there was greater activation in more posterior parts of the medial frontal and insular cortex whereas the reproduction phase involved more anterior parts of these brain structures. Intriguingly, activation curves over time show an accumulating pattern of neural activity, which peaks at the end of the interval within bilateral posterior insula and superior temporal cortex when individuals are presented with 9- and 18-s tone intervals. This is consistent with an accumulator-type activity, which encodes duration in the multiple seconds range. Given the close connection between the dorsal posterior insula and ascending internal body signals, we suggest that the accumulation of physiological changes in body states constitutes our experience of time. This is the first time that an accumulation function in the posterior insula is detected that might be correlated with the encoding of time intervals.

}, keywords = {Adult, Analysis of Variance, Brain Mapping, Cerebral Cortex, Factor Analysis, Statistical, Female, Humans, Image Processing, Computer-Assisted, Magnetic Resonance Imaging, Male, Neuropsychological Tests, Oxygen, Reaction Time, Time Factors, Time Perception, Young Adult}, issn = {1873-3514}, doi = {10.1016/j.neuropsychologia.2010.06.023}, author = {Wittmann, Marc and Simmons, Alan N and Aron, Jennifer L and Paulus, Martin P} } @article {191, title = {Spatiotemporal dynamics of bilingual word processing.}, journal = {Neuroimage}, volume = {49}, year = {2010}, month = {2010 Feb 15}, pages = {3286-94}, abstract = {

Studies with monolingual adults have identified successive stages occurring in different brain regions for processing single written words. We combined magnetoencephalography and magnetic resonance imaging to compare these stages between the first (L1) and second (L2) languages in bilingual adults. L1 words in a size judgment task evoked a typical left-lateralized sequence of activity first in ventral occipitotemporal cortex (VOT: previously associated with visual word-form encoding) and then ventral frontotemporal regions (associated with lexico-semantic processing). Compared to L1, words in L2 activated right VOT more strongly from approximately 135 ms; this activation was attenuated when words became highly familiar with repetition. At approximately 400 ms, L2 responses were generally later than L1, more bilateral, and included the same lateral occipitotemporal areas as were activated by pictures. We propose that acquiring a language involves the recruitment of right hemisphere and posterior visual areas that are not necessary once fluency is achieved.

}, keywords = {Adolescent, Adult, Brain, Brain Mapping, Female, Functional Laterality, Humans, Magnetoencephalography, Male, Multilingualism, Nerve Net, Pattern Recognition, Visual, Reading, Semantics, Young Adult}, issn = {1095-9572}, doi = {10.1016/j.neuroimage.2009.12.009}, author = {Leonard, Matthew K and Brown, Timothy T and Travis, Katherine E and Gharapetian, Lusineh and Hagler, Donald J and Dale, Anders M and Elman, Jeffrey L and Halgren, Eric} } @article {194, title = {Atypical face versus object processing and hemispheric asymmetries in 10-month-old infants at risk for autism.}, journal = {Biol Psychiatry}, volume = {66}, year = {2009}, month = {2009 Nov 15}, pages = {950-7}, abstract = {

BACKGROUND: Previous studies have documented atypicalities in face/object processing in children and adults with autism spectrum disorders (ASDs). To investigate whether such atypicalities may reflect a genetically mediated risk factor present early in development, we measured face/object processing in 10-month-old high-risk infants who carry some of the genes associated with ASD because they have an older sibling diagnosed with the disorder.

METHODS: We employed event-related potentials (ERPs) to measure cortical responses to pictures of faces and objects, the objects being toys. Latencies and amplitudes of four ERP components (P100, N290, P400, and Nc) were compared between 20 high-risk infants and 20 low-risk control subjects (infants with no family history of ASD).

RESULTS: Responses to faces versus objects differed between high- and low-risk infants for the latencies of the N290 and P400. Differences were driven by faster responses to faces than objects in low-risk, but not high-risk, infants (P400) and, conversely, faster responses to objects than faces in high-risk, but not low-risk, infants (N290). Object responses were also faster in high-risk than low-risk infants (both N290 and P400). Left versus right hemisphere responses also differed between high- and low-risk infants for the amplitudes of the P100, N290, and P400; collapsed across faces/objects, low-risk, but not high-risk, infants exhibited hemisphere asymmetries.

CONCLUSIONS: Genetic risk for ASD is associated with atypical face versus object processing and an atypical lack of hemispheric asymmetry early in life. These atypicalities might contribute to development of the disorder.

}, keywords = {Analysis of Variance, Autistic Disorder, Brain, Brain Mapping, Cerebral Cortex, Child, Child, Preschool, Electroencephalography, Evoked Potentials, Face, Female, Fourier Analysis, Functional Laterality, Humans, Infant, Male, Neuropsychological Tests, Pattern Recognition, Visual, Photic Stimulation, Reaction Time, Risk}, issn = {1873-2402}, doi = {10.1016/j.biopsych.2009.07.031}, author = {McCleery, Joseph P and Akshoomoff, Natacha and Dobkins, Karen R and Carver, Leslie J} } @article {184, title = {Effects of gestational length, gender, postnatal age, and birth order on visual contrast sensitivity in infants.}, journal = {J Vis}, volume = {9}, year = {2009}, month = {2009}, pages = {19.1-21}, abstract = {

To investigate effects of visual experience versus preprogrammed mechanisms on visual development, we used multiple regression analysis to determine the extent to which a variety of variables (that differ in the extent to which they are tied to visual experience) predict luminance and chromatic (red/green) contrast sensitivity (CS), which are mediated by the magnocellular (M) and parvocellular (P) subcortical pathways, respectively. Our variables included gestational length (GL), birth weight (BW), gender, postnatal age (PNA), and birth order (BO). Two-month-olds (n = 60) and 6-month-olds (n = 122) were tested. Results revealed that (1) at 2 months, infants with longer GL have higher luminance CS; (2) at both ages, CS significantly increases over a approximately 21-day range of PNA, but this effect is stronger in 2- than 6-month-olds and stronger for chromatic than luminance CS; (3) at 2 months, boys have higher luminance CS than girls; and (4) at 2 months, firstborn infants have higher CS, while at 6 months, non-firstborn infants have higher CS. The results for PNA/GL are consistent with the possibility that P pathway development is more influenced by variables tied to visual experience (PNA), while M pathway development is more influenced by variables unrelated to visual experience (GL). Other variables, including prenatal environment, are also discussed.

}, keywords = {Age Factors, Analysis of Variance, Birth Order, Color Perception, Contrast Sensitivity, Female, Gender Identity, Gestational Age, Humans, Infant, Light, Male, Regression Analysis}, issn = {1534-7362}, doi = {10.1167/9.10.19}, author = {Dobkins, Karen R and Bosworth, Rain G and McCleery, Joseph P} } @article {142, title = {Selection, gene interaction, and flexible gene networks.}, journal = {Cold Spring Harb Symp Quant Biol}, volume = {74}, year = {2009}, month = {2009}, pages = {131-8}, abstract = {

Recent results from a variety of different kinds of experiments, mainly using behavior as an assay, and ranging from laboratory selection experiments to gene interaction studies, show that a much wider range of genes can affect phenotype than those identified as "core genes" in classical mutant screens. Moreover, very pleiotropic genes can produce specific phenotypes when mild variants are combined. These studies also show that gene networks readily change configuration and the relationships between interacting genes in response to the introduction of additional genetic variants, suggesting that the networks range widely and have a high degree of flexibility and malleability. Such flexibility, in turn, offers a plausible mechanism for the molding of phenotypes through microevolution, as a prerequisite to making a suitable environment for the acceptance of newly arising large-effect mutations in the transition from microevolution to macroevolution.

}, keywords = {Animals, Biological Evolution, Drosophila melanogaster, Epistasis, Genetic, Escherichia coli, Female, Gene Regulatory Networks, Genes, Insect, Genetic Association Studies, Male, Models, Genetic, Mutation, Selection, Genetic}, issn = {1943-4456}, doi = {10.1101/sqb.2009.74.029}, author = {Greenspan, R J} } @article {150, title = {Identification of genes involved in Drosophila melanogaster geotaxis, a complex behavioral trait.}, journal = {Nat Genet}, volume = {31}, year = {2002}, month = {2002 Aug}, pages = {349-53}, abstract = {

Identifying the genes involved in polygenic traits has been difficult. In the 1950s and 1960s, laboratory selection experiments for extreme geotaxic behavior in fruit flies established for the first time that a complex behavioral trait has a genetic basis. But the specific genes responsible for the behavior have never been identified using this classical model. To identify the individual genes involved in geotaxic response, we used cDNA microarrays to identify candidate genes and assessed fly lines mutant in these genes for behavioral confirmation. We have thus determined the identities of several genes that contribute to the complex, polygenic behavior of geotaxis.

}, keywords = {Animals, Animals, Genetically Modified, Behavior, Animal, DNA, Complementary, Drosophila melanogaster, Female, Genetics, Behavioral, Mutation, Oligonucleotide Array Sequence Analysis}, issn = {1061-4036}, doi = {10.1038/ng893}, author = {Toma, Daniel P and White, Kevin P and Hirsch, Jerry and Greenspan, Ralph J} } @article {152, title = {Correlates of sleep and waking in Drosophila melanogaster.}, journal = {Science}, volume = {287}, year = {2000}, month = {2000 Mar 10}, pages = {1834-7}, abstract = {

Drosophila exhibits a circadian rest-activity cycle, but it is not known whether fly rest constitutes sleep or is mere inactivity. It is shown here that, like mammalian sleep, rest in Drosophila is characterized by an increased arousal threshold and is homeostatically regulated independently of the circadian clock. As in mammals, rest is abundant in young flies, is reduced in older flies, and is modulated by stimulants and hypnotics. Several molecular markers modulated by sleep and waking in mammals are modulated by rest and activity in Drosophila, including cytochrome oxidase C, the endoplasmic reticulum chaperone protein BiP, and enzymes implicated in the catabolism of monoamines. Flies lacking one such enzyme, arylalkylamine N-acetyltransferase, show increased rest after rest deprivation. These results implicate the catabolism of monoamines in the regulation of sleep and waking in the fly and suggest that Drosophila may serve as a model system for the genetic dissection of sleep.

}, keywords = {Animals, Arylamine N-Acetyltransferase, Behavior, Animal, Biogenic Monoamines, Caffeine, Carrier Proteins, Circadian Rhythm, Cytochrome P-450 Enzyme System, Drosophila melanogaster, Drosophila Proteins, Fatty Acid Synthases, Female, Gene Dosage, Gene Expression Profiling, Genes, Insect, Homeostasis, HSC70 Heat-Shock Proteins, HSP70 Heat-Shock Proteins, Hydroxyzine, Mutation, Rest, Sleep, Transcription, Genetic, Wakefulness}, issn = {0036-8075}, author = {Shaw, P J and Cirelli, C and Greenspan, R J and Tononi, G} } @article {154, title = {Genetic feminization of brain structures and changed sexual orientation in male Drosophila.}, journal = {Science}, volume = {267}, year = {1995}, month = {1995 Feb 10}, pages = {902-5}, abstract = {

The neural basis of sexual orientation in Drosophila was studied by the production of males with regionally feminized brains. Such flies express the female form of the sex determination gene transformer in a limited number of neurons under the control of GAL4 enhancer trap inserts. This method facilitated the creation of lines with a stable pattern of feminization. In tests of sexual preferences, flies that were feminized in a portion of the antennal lobes or in a subset of the corpora pedunculata (mushroom bodies) courted both males and females. These two brain structures, both of which are involved in olfactory processing, may function in the recognition of sex-specific pheromones, in the control of sex-specific behaviors, or both.

}, keywords = {Animals, Bisexuality, Brain, Drosophila melanogaster, Female, Genes, Insect, Male, Sex Attractants, Sexual Behavior, Animal, Smell}, issn = {0036-8075}, author = {Ferveur, J F and St{\"o}rtkuhl, K F and Stocker, R F and Greenspan, R J} } @article {155, title = {Understanding the genetic construction of behavior.}, journal = {Sci Am}, volume = {272}, year = {1995}, month = {1995 Apr}, pages = {72-8}, keywords = {Animals, Drosophila melanogaster, Female, Genetics, Behavioral, Humans, Male, Sexual Behavior, Animal}, issn = {0036-8733}, author = {Greenspan, R J} }