Hippocampal activation during processing of previously seen visual stimulus pairs

Öngür, Dost; Zalesak, Martin; Weiss, Anthony P.; Ditman, Tali; Titone, Debra; Heckers, Stephan

doi:10.1016/j.pscychresns.2005.05.006

« Previous Next »Psychiatry Research: Neuroimaging
Volume 139, Issue 3 , Pages 191-198, 30 August 2005

Hippocampal activation during processing of previously seen visual stimulus pairs

Dost Öngür
- Schizophrenia and Bipolar Disorder Program, McLean Hospital, 115 Mill St., AB 347, Belmont, MA, USA
- Corresponding author. Tel.: +1 617 855 3922; fax: +1 617 855 2895.
- These authors contributed equally to this manuscript.
Martin Zalesak
- Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, USA
- These authors contributed equally to this manuscript.
Anthony P. Weiss
- Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, USA
Tali Ditman
- Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, USA
Debra Titone
- Department of Psychology, McGill University, Montreal, Quebec, Canada
Stephan Heckers
- Schizophrenia and Bipolar Disorder Program, McLean Hospital, 115 Mill St., AB 347, Belmont, MA, USA
- Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, USA

Received 13 October 2004; received in revised form 28 February 2005; accepted 16 May 2005.

Abstract

Activity in the hippocampus is modulated by novelty detection, and by the processing of conjunctions between two stimuli. We investigated whether the hippocampus is activated by discrimination of stimulus–stimulus relationships in novel versus familiar pairs of visual stimuli in 15 healthy subjects using functional magnetic resonance imaging. Subjects were asked to recognize the previously rewarded stimulus in each case. We found significantly greater activation of the right hippocampus when discriminating previously seen compared with novel pairs of visual stimuli. This activation was evident in individual subjects and was not related to stimulus novelty, reward contingency, or task instruction. Right hippocampal activation during discrimination of previously seen pairs of objects was correlated with activity in the anteromedial thalamus, cingulate cortex, and contralateral hippocampus.

Keywords: Hippocampus, Neuroimaging, fMRI, Paired object recognition, Configural memory