Attentional competition between visual stimuli in healthy individuals and neurological patients

摘要: In the rich and complex visual environment that surrounds us, stimuli compete for attention in a limited capacity perceptual system (Broadbent, 1958; Duncan, 1980; Treisman, 1969). this competition, winners reach awareness losers are disregarded fail to (Ward, Goodrich & Driver, 1994; Mattingley, Davis 1997). Theories of can be guided informed by study brain damaged patients who show specific impairments attending stimuli, particular extinction, commonly following right hemisphere damage resulting an inability perceive contralesional stimulus when it appears with simultaneous ipsilesional item, but no such impairment alone. The studies reported thesis created extinction-like pattern errors healthy volunteers using bottom-up (stimulus- driven) paradigm simple task detection was employed. When more demanding identification employed, both top-down (cueing) paradigms, rarely previously described anti-extinction observed, which perception weaker item facilitated (rather than impaired) ‘stronger’ display. Extinction were then explored patients. A novel ‘attentional waiting’ hypothesis discussed, proposes extinction may part same attentional mechanism where latter manifestation observed larger proportion showing if duration is increased.