ABSTRACT
We studied the influence of attention on the timecourse of Stroop-like conflict. Thirty-two volunteers performed a Stroop matching task in which they had to compare either the color (n = 16) or meaning (n = 16) of two stimuli. The first stimulus was always a color-name printed in yellow, red, or blue (i.e., Stroop stimulus), and the second stimulus was either a color-bar (Experiment 1) or color-word in white ink (Experiment 2). Stimulus onset asynchrony (SOA) was varied parametrically. Interference by incongruent Stroop stimuli was clearly modulated by SOA manipulation in both cases. The results are discussed in terms of interactions between translational and attentional models in which the degree of Stroop-like interference is attributed to time implementation of attentional mechanisms during color-to-color and color-to-word matching contexts
Subject(s)
Humans , Male , Female , Young Adult , Reaction Time , Attention , Stroop Test , CognitionABSTRACT
The frontal eye field (FEF) of monkeys has been repeatedly implicated in the generation of saccadic eye movements by various experimental approaches. Electrical stimulation of most of the FEF produces saccadic eye movements, many cells have activities related to saccades, and it has anatomical connections with many other oculomotor ares. Surprisingly, complete lesions of the FEF have remarkably little effect on oculomotor behavior. Only when more cognitive aspects are tested is a deficit clearly detected. In contrast, acute inactivation of the FEF on monkeys with the GABA agonist muscimol produced much more severe oculomotor impairment. This difference is probably due to the acute nature of the muscimol effect, which does not allow time for reorganization of the control of eye movements before testing begins. In addition, acute activation of the FEF with the GABA antagonist bicuculline caused the monkey to make irrepressible saccades of the same dimensions as those electrically elicited at the site. These experiments further confirm the strong involvement of the FEF in the control of saccadic eye movements and fixation.