McGaughy JA, Rubin S, Stollstorff M, Baxter MG, Eichenbaum HB (2002) 192 IgG-saporin-induced cortical, cholinergic deafferentation in rats produces a dissociation in the function of prelimbic/infralimbic and orbitofrontal cortex in an attentional set-shifting task. Neuroscience 2002 Abstracts 674.4. Society for Neuroscience, Orlando, FL.
Summary: Converging data support the hypothesis that cholinergic afferents to the cortex mediate attentional processes. Rats with selective cholinergic lesions of the nucleus basalis magnocellularis produced by 192 IgG-saporin (SAP) show deficits in attentional performance. These deficits are highly correlated with diminished cholinergic efflux in the infralimbic/prelimbic (IL/PL) cortex during attentional testing. Excitotoxic lesions of the IL/PL in rats trained in an attentional set-shifting task did not impair the initial discimination, a novel discrimination with the previously relevant dimension (intradimensional shift; IDS) or reversal learning, but did impair the ability to shift attention to the previously irrelevant stimulus dimension (extradimensional shifting; EDS). It is not known from the previous study whether the loss of cortical, cholinergic afferents alone would be sufficient to produce the EDS deficit. Consequently, infusions of SAP(0.01 μg/μl; 0.25 μl) were made into either the IL/PL or the orbitofrontal (OF) cortex. Rats were then trained in the same attentional set-shifting task. Subjects had to discriminate between stimuli based on one of two perceptual dimensions, odor or digging media with both dimensions present on all trials. Preliminary analyses show that neither OF nor IL/PL lesions impair the initial discrimination or the IDS. However, IL/PL lesions impair the EDS whereas OF lesions impair reversal learning. These data support dissociable roles of cholinergic afferents to OF and IL/PL in attentional set-shifting.
Related Products: 192-IgG-SAP (Cat. #IT-01)