INTERACTIONS BETWEEN LEARNING AND MEMORY SYSTEMS
The mammalian brain is organized into multiple, parallel neural systems that mediate different learning and memory processes. The hippocampus and amygdala occupy central positions in these memory systems, the former subserving episodic information within a spatiotemporal context, and the latter being critical for forming associations between emotive experiences and stimuli. The interaction between these systems can be co-operative, or competitive, although the factors which determine the exact nature of this interaction is unknown. Our research seeks to address two important questions:
To what extent is hippocampus- and amygdala-mediated information in reward and fear learning processed in distinct cortico-limbic-striatal loops, and
Does functional integration between information represented within these systems occur, and if so, how and where?
NEURAL AND NEUROCHEMICAL BASIS OF LEARNED APPROACH-AVOIDANCE DECISION MAKING
An approach-avoidance decision making involves the evaluation of the incentive value of stimuli based on innate knowledge and learned experiences. It is particularly important when we experience motivational conflict upon an encounter with ambivalent information. Deficits in approach avoidance conflict resolution are a notable feature of many psychological disease – for instance, in drug addiction, addicts may show increased tendencies to ‘approach’ drugs of abuse, even in the face of negative consequences. In contrast, in depression and anxiety, one may see the opposite tendency of avoidance predominate.
We are interested in understanding the neural and neurochemical basis of innate and cue-induced approach avoidance conflict resolution, with a particular focus on the role of limbic-striatal circuits and dopaminergic mechanisms, and the use of maze-based and operant paradigms.
We also use pharmacological models of mental disorders to explore how approach-avoidance decision making goes awry in addiction, depression and schizophrenia.
Our research is, and was
GRATEFULLY FUNDED BY...
The Wellcome Trust, UK
Human Frontiers Science Program
Natural Sciences and Engineering Research Council (NSERC), Canada
Canadian Institutes of Health Research (CIHR)
Connaught Foundation, Canada
University of Toronto Scarborough