Pamela D. Butler, PhD, Director
Isaac Schechter, PsyD, Research Scientist
Dongsoo Kim, PhD, Research Scientist
Vance Zemon, PhD, Consultant
Maria Jalbrzikowski, Research Assistant
Roey Pasternak, Research Assistant

The Experimental Psychopathology Laboratory is part of the Program in Cognitive Neuroscience and Schizophrenia, directed by Daniel C. Javitt, MD, PhD.

Sensory processing deficits constitute a central feature of schizophrenia and have been linked to functional outcome. The Experimental Psychopathology Laboratory focuses on understanding early sensory processing dysfunction in schizophrenia, particularly in the visual system, using combined psychophysical, electrophysiological, and MRI approaches. We have found deficits particularly in the magnocellular visual pathway (e.g., Butler et al., 2001; 2003), which conducts low-resolution visual information rapidly to cortex, and is involved in attentional capture and processing of overall stimulus organization. MRI studies of white matter integrity suggest that pathology may begin in the thalamus (dorsal lateral geniculate nucleus) or primary visual cortex and that this pathology is related to visual processing deficits (Butler et al., 2003).

Our research goals are: 1) to further characterize visual pathway dysfunction in schizophrenia; 2) to examine the role of magnocellular dysfunction in higher level cognitive deficits in schizophrenia; and 3) to examine structural correlates of visual processing dysfunction in schizophrenia.

Dr. Butler's work focuses on understanding the neural substrate of magnocellular dysfunction, including connections with N-methyl-D-aspartate (NMDA) dysfunction and with decreased white matter integrity. She is also examining relationships between magnocellular dysfunction and higher-level problems in schizophrenia such as emotion processing deficits. Dr. Schechter's work focuses on deficits in gestalt processing, illusions, and stereopsis - all of which involve magnocellular functioning (e.g., Schechter et al., 2004). He has also investigated the contributions of magnocellular and parvocellular systems to backward masking dysfunction in schizophrenia (e.g., Schechter et al., 2003). Dr. Kim's work focuses on lateral interactions in visual cortex and motion processing as well as high density ERP studies of visual deficits in schizophrenia (e.g., Kim et al., submitted). Dr. Vance Zemon, an expert in visual neuroscience, electrophysiology, and psychophysics is a consultant on our grant-funded projects (e.g, Zemon et al., submitted).

Our laboratory has collaborations with a number of other investigators. These include Dr. Daniel C. Javitt, director of the Program in Cognitive Neuroscience and Schizophrenia at the Nathan Kline Institute (NKI). His work is focused on understanding the neurobiology of schizophrenia - particularly with regard to early sensory processing problems and their functional consequences. We collaborate with Dr. John J. Foxe, director of the Cognitive Neurophysiology Laboratory at NKI (e.g, Leitman et al., submitted). His laboratory utilizes high-density ERP techniques and fMRI to study cognitive function. In addition, we collaborate with Drs. Matthew Hoptman and Kelvin Lim to examine white matter integrity in schizophrenia and with Dr. Nadine Revheim to examine relationships between visual processing deficits and social cognition/functional outcome. Drs. Hoptman and Revheim are at NKI and Dr. Lim is at the University of Minnesota.

Articles

Butler PD, Schechter I, Zemon V, Schwartz SG, Greenstein VC, Gordon J, Schroeder CE, Javitt, DC. Dysfunction of early stage visual processing in schizophrenia. Am J Psychiatry 2001;158:1126-1133.

Butler PD, DeSanti LA, Maddox J, Harkavy-Friedman J, Amador XF, Goetz RR, Javitt DC, Gorman JM. Visual backward-masking deficits in schizophrenia: relationship to visual pathway function and symptomatology. Schizophrenia Research 2002:59:199-209.

Butler PD, Lim KO, Nierenberg J, Hoptman MJ, Choi SJ, Schechter I, Zemon V, Saperstein AM, Javitt DC. Primary visual dysfunction in schizophrenia: relationship to white matter integrity inferred from diffusion tenson imaging. Schizophrenia Research 2003: 60(1):190.

Kim D, Zemon V, Saperstein A, Butler PD, Javitt DC. Dysfunction of early stage visual processing in schizophrenia: Harmonic analysis, submitted.

Leitman DL, Foxe JJ, Butler, PD, Saperstein A, Revheim N, Javitt DC. Early Sensory- Cortical Antecedents of Affective Speech Recognition Deficits in Schizophrenia, submitted

Schechter I, Butler PD, Silipo G, Zemon V, Javitt DC. Magnocellular and parvocellular contributions to backward masking dysfunction in schizophrenia. Schizophrenia Research 2003;64:91-101.

Schechter I, Pasternak R, Saperstein, AM, Butler, PD, Javitt DC. Adding a Dimension to Visual Deficits: Stereopsis Impairments in Schziophrenia. Biological Psychiatry, 2004: 55(8S):25S.

Zemon V, Butler PD, Gordon J, Jalbrzikowski M, Javitt DC, Piesco J, Russo J, Schechter I. Neural dysfunction in schizophrenia: contrast-response functions and a nonlinear model. Society for Neuroscience Abstracts, submitted.

For further information, contact Dr. Butler at