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Education

• Ph.D., Boston University
• Post Doc Fellowship, University of California
• George Washington University

Research Interests

• The neural basis of visual short-term memory-ÌýÌýÌýA critical question in human cognition is how the brain maintains information across eye movements and distraction. Without this capacity, we would experience the outside world as a series of disconnected glimpses. Between the visual system and frontal cortex, activity in areas of the dorsal parietal cortex, also involved in visual attention, reflect the number of items held in visual short-term memory.ÌýTo what degree do the mechanismsÌýÌýin theÌýparietal cortex that support memory overlap with visual attention mechanisms? What can this brain activity tell us about the processes underlying visual short-term memory and attention?
  Hemispheric asymmetries in visual attention and short-term memory-ÌýÌýFrom the earliest stages, visual information is separated into left and right visual hemifields, each processedÌýby cortical areas in the opposite, or contralateral, hemisphere. I am currently investigating how the differences in visual field representations across cortical areas result in how weÌýperceive a unified world.ÌýHow does the right parietal cortex code information not only from the left, or contralateral, hemifieldÌýÌýbut from across the visual field? What can asymmetries in healthy individuals reveal about neuropsychological disorders such as hemispatial neglect, which occur predominantly after damage to the right hemisphere? What are the behavioral consequences of these asymmetries in healthy individuals?

  Ventral parietal cortex involvement in memory and attention-ÌýÌýThe angular gyrus, adjacent toÌýtopogaphicallyÌýdefined parietal cortex, is a part of an attention network that shows reduced activity when we hold visual items in memory. However, this area has also been implicated in a myriad of cognitive functions including binding of visual features in the right hemisphere and binding of visual and semantic information in the left hemisphere.ÌýHow can we reconcile these functions of the angular gyrus? Can we localize areas of the ventral parietal cortex involved in specific cognitive processes?

Recent Publications

Sheremata, S.L., Shomstein, S. (under review) Task set induces dynamic reallocation of resources in visual short-term memory.Ìý

Sheremata, S.L., Silver, M.A.Ìý(2015)ÌýHemisphere-dependent attentional modulation ofÌýhuman parietalÌývisual field representations.ÌýJournal of NeuroscienceÌý35(2): 508-17.ÌýÌý

Sheremata, S.L.,ÌýShomstein, S. (2014)ÌýHemifield asymmetries differentiate VSTM for single- and multiple-feature objects.ÌýAttention, Perception, & PsychophysicsÌý76(6) 1609-19.ÌýÌý

Yoon, J.,ÌýSheremata, S.L., Rokem, A., Silver, M.A. (2013) Windows to the soul: Vision science as a tool for studying biological mechanisms of information processing deficits in schizophrenia.ÌýFrontiers in PsychopathologyÌý4(681).ÌýÌý

Somers, D.C.,ÌýSheremata, S.L.Ìý(2013) Attention maps in the brainÌýWIREs Cognitive Science: Cognitive ScienceÌý4(4) 327-40.ÌýÌý

Kong, L., Michalka, S.W., Rosen, M.L.,ÌýSheremata, S.L., Swisher, J.D., Shinn-Cunningham, B.S., Somers, D.C. (2012) Auditory spatial attention representations in the human cerebral cortexÌýCerebral Cortex.

Kosovicheva, A.K.,ÌýSheremata, S.L., Rokem, A., Landau, A.N., Silver, M.A. (2012) Cholinergic enhancement reduces orientation-specific surround suppression but not visual crowdingÌýFrontiers in Behavioral NeuroscienceÌý6(61).ÌýÌý

Sheremata, S.L.,ÌýBettencourt, K.C., Somers, D.C. (2010) Hemispheric asymmetry in visuotopic posterior parietal cortex emerges with visual short-term memory loadÌýJournal of NeuroscienceÌý30(38):12581-8.ÌýÌý

Sheremata, S.L., Sakagami M. (2006) Increasing distractor strength improves accuracyÌýPerceptual and Motor SkillsÌý102(2): 509-516.Ìý

Chen, Y., Levy, D.L.,ÌýSheremata, S.L., Holzman, P.S. (2006) Bipolar and schizophrenic patients differ in patterns of visual motion discriminationÌýSchizophrenia ResearchÌý88(1-3):208-216.ÌýÌý

Sheremata, S.L., Chen, Y. (2004) Co-administration of atypical antipsychotics and antidepressants disturbs contrast detection in schizophrenia.Schizophrenia ResearchÌý70(1):81-89.ÌýÌý

Chen, Y., Levy, D.L.,ÌýSheremata, S.L., Holzman, P.S.Ìý(2004) Compromised late-stage motion processing in schizophreniaÌýBiological PsychiatryÌý55(8):834-41.ÌýÌý

Chen, Y., Levy, D.L.,ÌýSheremata, S.L., Nakayama, K., Matthysse, S., Holzman, P.S.Ìý(2003) Effects of typical, atypical, and no antipsychotic drugs on visual contrast detection in schizophrenia.ÌýAmerican Journal of PsychiatryÌý160(10):1795-801.ÌýÌý

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Scholarly Activities