(e.g., an observer is instructed to detect a red tilted : Différence entre versions

Version du 27 janvier 2018 à 14:22

Support for this proposal comes from studies in which cueing relevant characteristics (either size or color) aided functionality in visual search tasks, below some circumstances, by prioritizing processing of these stimuli and guiding spatial consideration to them just before other individuals (Moore Egeth, 1998; Shih Sperling, 1996). Even though these two studies conclude title= s12864-016-2896-7 that FBA will not enhance the signal, other behavioral and neurophysiological studies have offered evidence of enhancement. Also relevant for the role of FBA in visual search would be the getting that the impact of function guidance title= bmjopen-2016-012517 increases when a selection bias can make more than successive trials simply because the target function remains the same from trial to trial (Carrasco, Ponte, Rechea, Sampedro, 1998; Muller, Heller, Ziegler, 1995; Wolfe, Butcher, Lee, Hyle, 2003; Wolfe Horowitz, 2004). Single-unit recordings have provided direct evidence for feature choice for the duration of visual search: the responses of individual neurons are enhanced when attention is deployed to the function value they may be selective for (e.g., vertical orientation, upward motion direction or red colour). Many studies have examined region V4, that is critically involved in intermediate stages of visual processing, and implicated in figure-ground segmentation, grouping, kind recognition, shape perception, visual search and colour (Gallant, Shoup, Mazer, 2000; Pasupathy Connor, 1999; Schiller, 1995; Schiller Lee, 1991). Dynamic tuning shifts in V4 play a important part in these processes. As an illustration, an early study recommended that FBA may possibly adjust color selectivity, resulting in improved sensitivity to behaviorally relevant functions (Motter, 1994a, 1994b). Monkeys viewed arrays of mixed stimuli and had to attend to a subset of stimuli using a colour or luminance that matched a cue stimulus. V4 responses have been title= 2016/5789232 stronger when the stimulus in their receptive Odanacatib fields matched the cue. The response of V4 neurons was stronger to objects in their receptive fields that had the neurons' preferred options when the objects had been the search targets than once they were distractors (Bichot, Rossi, Desimone, 2005). Related benefits have been obtained in area MT when monkeys searched for targets defined by conjunctions of color and motion path (Buracas Albright, 2009).(e.g., an observer is instructed to detect a red tilted target amongst red vertical distractors), it would be useful for the observer to grant priority in processing tilted characteristics, or to boost their representation. In the case of conjunction search, an observer can be instructed to detect a red tilted target, or to discriminate its tilt (left vs. right), amidst blue tilted and red vertical distracters. Within this case, it will be helpful for the observer to prioritize the processing of red and/or tilted products. Certainly, some authors have proposed that an early stage on the search approach would be to select the subset of stimuli that contain no less than one of the target's functions (e.g., Egeth, Virzi, Garbart, 1984; McElree Carrasco, 1999; Wolfe Horowitz, 2004). Assistance for this proposal comes from research in which cueing relevant functions (either size or colour) aided performance in visual search tasks, under some situations, by prioritizing processing of those stimuli and guiding spatial interest to them ahead of other people (Moore Egeth, 1998; Shih Sperling, 1996).