Waite JJ (1999) Cholinergic deafferentation of the hippocampus or cortex produces differential modulation of attentional processing. Neuroscience 1999 Abstracts 754.4. Society for Neuroscience, Miami, FL.
Summary: Dissociation of attentional changes produced by lesion of the cholinergic neurons in the medial septum (MS) and nucleus basalis magnocellularis (NBM) was investigated by selective lesion with the immunotoxin 192 IgG-saporin followed by testing in the multiple choice serial reaction time task. Male F-344 rats were trained in the 5-choice reaction time task. After criterion performance was attained, the toxin was administered intraparenchymally into the MS (75 ng/site bilateral) and/or NBM (150 ng/site bilateral) to selectively destroy cholinergic neurons projecting to hippocampus and cortex, respectively. Residual ChAT activity, expressed as percent of PBS-infused control, was: in frontal cortex, 28% (NBM); 88% (MS); and 21% (NBM+MS); in hippocampus, 103% (NBM); 18% (MS); and 19% (NBM+ MS). Animals reacquired the baseline task to equivalent levels among groups, based on both accuracy and omissions within ten sessions. MS rats performed with greatest accuracy when the intertrial interval (ITI) was short. They always had fewest omissions. Accuracy for this group suffered when the ITI was long and when a noise was presented just before the light stimulus. NBM rats had the most omissions, but accuracy was generally as good or better than controls and the MS group. Rats with both MS and NBM lesions were frequently between MS and NBM performance curves, putting them close to controls in many tests. They performed worse than all groups in terms of accuracy when the ITI was short and when the light intensity was reduced. Thus, the double lesion had an additive effect when the salience of stimulus was reduced and when the frequency of trials was faster. Supported by NIH NS33371.
Related Products: 192-IgG-SAP (Cat. #IT-01)