Neural correlates of prefrontal cortex-hippocampus interactions during hippocampus-dependent cognitive functions
Impairments in cognitive functions in patients with depression, schizophrenia, and age-related mental decline have been repeatedly associated with altered hippocampal-prefrontal interactions which can be modulated by changes in the dopamine system. Contextual fear-conditioning and source memory paradigms are model tasks for quantifying such hippocampal-prefrontal interactions and are known to be impaired in schizophrenia, depression, and healthy ageing.
Dysfunction of the hippocampus and the prefrontal cortex should be evident by a modified recruitment and connectivity as revealed by both functional magnetic resonance imaging (fMRI) and event-related potentials (ERPs) in multi-channel electroencephalography (EEG), as well as in the analysis of neural oscillations and phase-locking in different frequency bands. New predictions derived from neurocomputational models developed in other subprojects of the BCCN will be tested by additional data analysis.
The subproject C6 will deliver neuropsychological assessment (e.g., executive functions, attention, and memory) of patients and control subjects using a computerized testing battery. To examine the effects of ageing, depression, schizophrenia and dopamine receptor density in contextual fear-conditioning, all subjects participate in an fMRI scanning session whereas effects on source memory will be tested on a subsample using ERPs.