Tuesday, August 23, 2005

Neuroscience and Biobehavioral Reviews - Neuroscience & Biobehavioral Reviews : Regional dissociations within the hippocampus—memory and anxiety

Regional dissociations within the hippocampus—memory and anxiety

D. M. Bannermana, J. N. P. RawlinsCorresponding Author Contact Information, E-mail The Corresponding Author, a, S. B. McHugha, R. M. J. Deacona, B. K. Yeeb, T. Bastb, 1, W. -N. Zhangb, H. H. J. Pothuizenb and J. Feldonb

a Department of Experimental Psychology, University of Oxford, South Parks Road, Oxford OX1 3UD, UK
b Laboratory of Behavioural Neurobiology, Swiss Federal Institute of Technology Zurich, Schorenstrasse 16, Schwerzenbach CH-8603, Switzerland

Available online 24 June 2004.


Abstract

The amnestic effects of hippocampal lesions are well documented, leading to numerous memory-based theories of hippocampal function. It is debatable, however, whether any one of these theories can satisfactorily account for all the consequences of hippocampal damage: Hippocampal lesions also result in behavioural disinhibition and reduced anxiety. A growing number of studies now suggest that these diverse behavioural effects may be associated with different hippocampal subregions. There is evidence for at least two distinct functional domains, although recent neuroanatomical studies suggest this may be an underestimate. Selective lesion studies show that the hippocampus is functionally subdivided along the septotemporal axis into dorsal and ventral regions, each associated with a distinct set of behaviours. Dorsal hippocampus has a preferential role in certain forms of learning and memory, notably spatial learning, but ventral hippocampus may have a preferential role in brain processes associated with anxiety-related behaviours. The latter's role in emotional processing is also distinct from that of the amygdala, which is associated specifically with fear. Gray and McNaughton's theory can in principle incorporate these apparently distinct hippocampal functions, and provides a plausible unitary account for the multiple facets of hippocampal function.

Author Keywords: Hippocampus; Dorsal; Ventral; Amygdala; Spatial; Learning; Memory; Anxiety; Fear; Freezing; Startle

Monday, August 22, 2005

ScienceDirect - Intelligence : Second-to-fourth digit length, testosterone and spatial ability

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6W4M-4F49582-2&_user=1554326&_handle=V-WA-A-W-E-MsSAYVW-UUA-U-AAWDWADUEZ-AAWVDEDYEZ-WEVZCVZAY-E-U&_fmt=summary&_coverDate=06%2F30%2F2005&_rdoc=2&_orig=browse&_srch=%23toc%236546%232005%23999669996%23595079!&_cdi=6546&view=c&_acct=C000053158&_version=1&_urlVersion=0&_userid=1554326&md5=520aa771938a408c397744cd16d51184