Dissociation of the component processes of attention in healthy adults.

Cohen's [Cohen, R. (1993). The Neuropsychology of Attention. New York: Plenum Publishing] model of attention proposes four interrelated processes, namely Sensory Selective Attention, Response Selection/Control, Focus/Capacity, and Sustained Attention. Though this model has been supported in patient samples, it has not been examined in a healthy adult cohort. Using Principal Components Analysis, we examined the explanatory power of this model in 342 adults screened for significant medical and psychiatric history. The four derived components accounted for 58.7% of the total variance. Results were generally supportive of Cohen's [Cohen, R. (1993). The Neuropsychology of Attention. New York: Plenum Publishing] model, though further clarification of the relationship between processing speed and more complex aspects of attention (e.g. working memory, set shifting) is needed. These findings support the notion that attention is not a unitary process, but instead comprised of distinct components. Future studies including both neuropsychological testing and functional neuroimaging may provide important insight into the underpinnings of attentional processes.