Context- but not familiarity-dependent forms of object recognition are impaired following excitotoxic hippocampal lesions in rats.
Dual-process models of recognition memory in animals propose that recognition memory is supported by two independent processes that reflect the operation of distinct brain structures: a familiarity process that operates independently of the hippocampus and a context-dependent (episodic) memory process that is dependent on the hippocampus. A novel variant of an object recognition procedure was used to examine this proposal. Healthy rats showed a preference for exploring a novel object rather than a familiar object: a familiarity-dependent recognition effect. They also showed a preference for exploring a familiar object that was presented in a different spatiotemporal context rather than a familiar object that was presented either in a different spatial or temporal context: a context-dependent form of recognition that is sensitive to "what" object has been presented "where" and "when." Rats with excitotoxic hippocampal lesions showed the familiarity-dependent but not the context-dependent form of recognition. The results provide support for dual-process theories of recognition memory.
Good
M A
MA
School of Psychology, Cardiff University, Cardiff, United Kingdom. good@cardiff.ac.uk
Barnes
P
P
Staal
V
V
McGregor
A
A
Honey
R C
RC
D000818:Animals; D001930:Brain Injuries / Q000139:chemically induced / Q000150:complications* / Q000473:pathology; D006624:Hippocampus / Q000187:drug effects / Q000503:physiopathology*; D007051:Ibotenic Acid; D008297:Male; D008569:Memory Disorders / Q000209:etiology*; D011939:Mental Recall / Q000187:drug effects / Q000502:physiology*; D009483:Neuropsychological Tests; D010364:Pattern Recognition, Visual / Q000187:drug effects / Q000502:physiology*; D051381:Rats
D007051:Ibotenic Acid