Tait DS, Brown VJ (2004) Cell-body lesions of basal forebrain impair reversal learning but not attentional set-shifting in rats. Neuroscience 2004 Abstracts 779.12. Society for Neuroscience, San Diego, CA.
Summary: There is considerable evidence for a role of basal forebrain acetylcholine in a wide range of attentional tasks (see Sarter & Bruno, 2000, Neurosci, 95:933-952), but previous work from this laboratory found that basal forebrain cholinergic projections are not critical for the acquisition, maintenance and shifting of attentional set (Tait et al, 2002 SfN abstr 286.2). As GABAergic basal forebrain projections to cortex may be important for “cognitive flexibility” (Sarter & Bruno, 2002, Eur J Nsci, 15:1867-1873), the present study assessed the effects of non-specific basal forebrain lesions. Male Lister hooded rats received infusions of 200nl 0.06M ibotenic acid into basal forebrain, at coordinates: nosebar –3.3; AP –0.9; ML ±2.9; DV –6.9. We used the rat attentional-set shifting task (Birrell & Brown, 2000, JNsci, 20:4320-4324), in which rats forage in digging bowls for food rewards, to assess discrimination learning (based on the odor of the bowls or the medium in which the food was hidden), reversal learning and attentional-set shifting (when the relevant aspect of the stimulus is switched; for example, a rat previously attending to odor, now must attend to digging medium or vice versa). There was no impairment in discrimination acquisition or in shifting of attentional-set. Lesioned rats were impaired only on the first of three discrimination reversals, taking significantly longer to reach criterion than controls. Prior evidence indicating no effect of selective BF cholinergic depletion via 192-IgG-saporin administration on reversal performance (Tait et al, 2002) leads us to conclude that the non-cholinergic neurons – most likely the GABAergic projection to prefrontal cortex and thalamus – have an important role in reversal learning. These data are strikingly similar to the effects of excitotoxic basal forebrain lesions in monkeys (Roberts et al, 1992, NSci, 472:251-264).
Related Products: 192-IgG-SAP (Cat. #IT-01)