The aim of this study was to assess the effects of anxiety on attentional performance with neutral stimuli. It was set up as follows: a fourfold comparison was made of trait anxiety and state anxiety. Sixty-two undergraduate students were included in the study, and four groups of subjects were set up by a median split of the scores obtained on the Spielberger Trait and State Anxiety Inventory (STAI): high trait-high state (N = 18); high trait-low state (N = 11); low trait-low state (N = 23); low trait-high state (N = 10). A computerized battery of neuropsychological tests, the ACE battery, was administered to provide a multidimensional assessment of attention. The ACE battery comprises five tests which assess the following aspects of attention: ability to monitor a routine task; temporal preparation; visual detection; memory span; visual spatial attention and memory. High state anxious subjects displayed impairment in executive functions, manifested by a significantly higher level of motor preparation in a simple reaction time (RT) task and a speed accuracy trade-off in a divided attention task; high trait anxious subjects performed significantly better on the visual detection task. No trait × state interaction was found. It was concluded that high state anxiety is associated with psychomotor alertness and high trait anxiety with perceptual alertness. These two dimensions of psychometric anxiety seem to have effects on attention that are independent of one another and which should be analysed separately in the future.

Previous findings suggest that motoric response preparation cannot be initiated in parallel with memory scanning. In the present study, response preparation was initiated with the aid of a precue to examine whether such preparation can be maintained or continued while memory scanning is active. In Experiment 1, each trial began with a colored square indicating which hand might be needed to respond. A probe letter's memory set membership determined whether the primed response should be made or withheld. Lateralized readiness potentials were initiated by the square precue and continued to increase after letter presentation, suggesting that once response preparation had been initiated it was continued in parallel with memory scanning. Experiment 2 suggested that the difficulty of the concurrent memory search had little effect on the continuation of response preparation. The results support the view that motoric response preparation consists of at least two qualitatively distinct phases—initiation and continuation.

The effects on performance of unattended stimulus–response spatial relationships in choice reaction time tasks (i.e., the Simon effect) have been attributed to automatic activation of the response ipsilateral to stimulus location. We tested this assumption using the lateralized readiness potential (LRP). The response key labels changed randomly from trial to trial and were presented either 400 ms before (immediate-reaction trials) or 400 ms after (delayed-reaction trials) stimulus. The critical test for the automatic activation hypothesis was on delayed-reaction trials, in which LRP deflections were expected in the interval between stimulus and response-key labels. Contrary to this prediction, there were no LRP signs of response activation within that interval.

The effects on performance of unattended stimulus–response spatial relationships in choice reaction time tasks (i.e., the Simon effect) have been attributed to automatic activation of the response ipsilateral to stimulus location. We tested this assumption using the lateralized readiness potential (LRP). The response key labels changed randomly from trial to trial and were presented either 400 ms before (immediate-reaction trials) or 400 ms after (delayed-reaction trials) stimulus. The critical test for the automatic activation hypothesis was on delayed-reaction trials, in which LRP deflections were expected in the interval between stimulus and response-key labels. Contrary to this prediction, there were no LRP signs of response activation within that interval.