THE COGNITIVE NEUROPSYCHOLOGY OF ATTENTION - A FRONTAL-LOBE PERSPECTIVE

Recent research on the cognitive sequelae of focal frontal damage has significantly advanced our understanding of the role of the frontal lobes in attentional function. Although early studies using traditional psychometric tests had suggested that attention was not grossly impaired in patients with focal frontal lobe lesions, more recent studies have demonstrated deficits in dissociable capacities such as the direction of extrapersonal attention, selective attention, inhibition, orienting responses, habituation, and sustained attention. Behaviourally, these deficits may be manifested as distractibility, neglect, and impulsivity. There is some suggestion of localisation of attentional processes within the frontal cortex, with the right frontal lobe being particularly implicated in the mediation of sustained and directed attention. However, there does not yet appear to be any conclusive evidence in the focal frontal literature concerning the localisation of other attentional processes. Prescriptions for future research include more thorough replications of empirical data, the use of better designed control procedures to isolate component cognitive processes of attention, and the application of novel approaches and technologies such as neural network simulations and functional neuro-imaging.