Anterior medial temporal lobe in human cognition: memory for fear and the unexpected.
BACKGROUND
To survive, an organism must remember occurrences of value in its environment. These include those that pose a threat to survival, novel or unexpected stimuli, or a general class of stimuli that represent punishment or reward. There is substantial evidence that memory for novel and emotionally salient events is enhanced relative to familiar or emotionally neutral events.


METHODS
We present human functional magnetic resonance imaging (fMRI) experiments that address the neurobiological processes underlying upregulation of memory for novel or emotional events.


RESULTS
Enhanced memory for novel or unexpected stimuli is mediated by anterior hippocampus, whereas increased memory for emotional stimuli is mediated by a beta-adrenergic-dependent modulation of amygdala-hippocampal interactions. We introduce a hypothesis that medial temporal connectivity with autonomic control centres may be central to this memory enhancement.


CONCLUSIONS
Enhanced memory for stimuli that are of adaptive importance to survival is mediated by the anterior medial temporal lobe and effected via connections with the autonomic system.
Strange
Bryan A
BA
Institute of Neurology, London, UK. bstrange@fil.ion.ucl.ac.uk
Dolan
Raymond J
RJ
D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000679:Amygdala / Q000187:drug effects / Q000502:physiology; D001341:Autonomic Nervous System / Q000502:physiology; D003071:Cognition / Q000187:drug effects / Q000502:physiology*; D005239:Fear; D006624:Hippocampus / Q000187:drug effects / Q000502:physiology; D006801:Humans; D008568:Memory / Q000187:drug effects / Q000502:physiology*; D011939:Mental Recall / Q000187:drug effects; D011433:Propranolol / Q000494:pharmacology; D013702:Temporal Lobe / Q000187:drug effects / Q000502:physiology*
D000319:Adrenergic beta-Antagonists; D011433:Propranolol