Dissociation of attention in learning and action: effects of lesions of the amygdala central nucleus, medial prefrontal cortex, and posterior parietal cortex.
Many associative learning theories assert that the predictive accuracy of events affects the allocation of attention to them. More reliable predictors of future events are usually more likely to control action based on past learning, but less reliable predictors are often more likely to capture attention when new information is acquired. Previous studies showed that a circuit including the amygdala central nucleus (CEA) and the cholinergic substantia innominata/nucleus basalis magnocellularis (SI/nBM) is important for both sustained attention guiding action in a five-choice serial reaction time (5CSRT) task and for enhanced new learning about less predictive cues in a serial conditioning task. In this study, the authors found that lesions of the cholinergic afferents of the medial prefrontal cortex interfered with 5CSRT performance but not with surprise-induced enhancement of learning, whereas lesions of cholinergic afferents of posterior parietal cortex impaired the latter effects but did not affect 5CSRT performance. CEA lesions impaired performance in both tasks. These results are consistent with the view that CEA affects these distinct aspects of attention by influencing the activity of separate, specialized cortical regions via modulation of SI/nBM.