Biomedical subjects

Steven P Tipper

Publications and source records attributed to Steven P Tipper.

3 recordsLinked to original sources

PubMed2003

Long-term inhibition of return of attention.

During search of the environment, the inhibition of the return (IOR) of attention to already-examined information ensures that the target will ultimately be detected. Until now, inhibition was assumed to support search of information during one processing episode. However, in some situations search may have to be completed long after it was begun. We therefore propose that inhibition can be associated with an episode encoded into memory such that later retrieval reinstates inhibitory processing and encourages examination of new information. In two experiments in which attention was drawn to face stimuli with an exogenous cue, we demonstrated for the first time the existence of long-term IOR. Interestingly. this was the case only for faces in the left visual field, perhaps because more efficient processing of faces in the right hemisphere than the left hemisphere results in richer, more retrievable memory representations.

Adolescent↗

PubMed2002

Object-based representations facilitate memory for inhibitory processes.

Previous work has shown that in a sequential cueing task, inhibition of the return of attention (IOR) can be observed for up to four or five loci. We have argued that the inhibition processes mediating IOR are associated with object-based representations, and it is object-based representations that are maintained in memory. Experiments presented here show that, compared with standard conditions in which a number of identical grey squares are cued, cueing empty locations tends to reduce the memory for prior inhibitory processes; while cueing objects which are distinctive in colour and shape tends to increase memory for inhibition. Converging with other recent findings, we conclude that memory for the inhibitory processes of attention facilitates visual search and that this memory is dependent on object-based representations.

Attention↗

PubMed2002

A rapid effect of caffeinated beverages on two choice reaction time tasks.

Though consumers of tea and coffee can report feeling beneficial subjective effects of consumption virtually immediately, tests for objective effects of caffeine immediately post-consumption have been rare. Two experiments examined caffeine's ability to influence reaction time in choice reaction time tasks, using a dose of caffeine typical of a cup of tea or instant coffee, and testing at short post-consumption delays. Two groups of participants were given 60 mg of caffeine, after overnight abstinence, either in a hot tea drink, or a hot water drink. Two control groups also received hot tea or water, but without caffeine. In Experiment 1, participants were given a keypress task before the drink (baseline), immediately after the drink, and 40 min after the drink. In Experiment 2, a touch-screen test was given either 1, 14, or 27 min post consumption. Caffeine was found to reduce the effect of a distracter on reaction time in the keypress test and to reduce reaction time in a component of the touch-screen task; however, in neither experiment were these effects significantly modulated by post-consumption delay length. Thus, the speed of caffeine's action on psychomotor performance was shown to be on the order of minutes.

Adolescent↗