Logical studies--Measurements of activity in visual cortex have offered the neural

As an example, a study combining fMRI and neuromagnetic recordings discovered that a moving stimulus elicited a bigger neural response in title= bmjopen-2016-012517 the motionsensitive region MT when movement was relevant than when colour was relevant, whereas a color-change stimulus developed greater activity in the color-selective region V4/V8 when color was attended than when movement was relevant (Schoenfeld et al., 2007). Neuroimaging studies have also shown FBA modulation of targets which might be spatially coextensive with distractors of various feature values. For example, attending to a single colour in a show containing intermingled colored moving dots increases the amplitude ofVision Res. Author manuscript; out there in PMC 2012 July 05.NIH-PA Author Manuscript NIH-PA Author Manuscript NIH-PA Author ManuscriptCarrascoPageSSVEPs to that colour in comparison with when that colour isn't attended (Muller et al., 2006). Research applying voxel-based multivariate pattern classification overcome the spatial resolution limitations of fMRI, as a result enabling the assessment of featural attentional effects in precise retinotopic visual locations. When participants attended to 1 of two superimposed grid patterns, a classifier determined by voxels from V1 to V4 could reliably predict the attended orientation (Kamitani Tong, 2005). Consideration increases the BOLD response in voxels tuned for the attended orientation (or close to it), relative to voxels tuned title= 2016/5789232 for the unattended orientation. Constant with the feature-similarity gain model, this pattern of responses suggests that attending to one particular orientation biased the population activity toward the attended orientation, the behaviorally relevant stimuli, in the get SMS 201995 expense of behaviorally irrelevant stimuli (see also Serences Boynton, 2007; Serences, Saproo, Scolari, Ho, Muftuler, 2009). A different valuable approach to investigate FBA across many locations in human visual cortex is fMRI response adaptation. Measurements of adaptation with fMRI permit scientists to create title= fmicb.2016.01271 inferences about neural activity at the subpopulation level beyond the resolution of a single image voxel (Grill-Spector Olmutinib site Malach, 2001; Krekelberg, Boynton, van Wezel, 2006). The fMRI adaptation method was employed in mixture with psychophysics to investigate the selective energy, perceptual consequences and neural basis of F.Logical studies--Measurements of activity in visual cortex have supplied the neural correlates of FBA. FBA selectively modifies the neural representations of elements inside visual scenes that match the at present attended function. An early study of FBA in location V4 illustrates this modification. Monkeys were trained to view a fast sequence of gratings and to respond once they saw a grating that matched the orientation of a cue grating. The responses of most recorded neurons varied according to which orientation the animal was searching for (Haenny et al., 1988; see also Hayden Gallant, 2005; Maunsell et al., 1991). The neural signatures of FBA have also been investigated using neuroimaging tactics. Early PET and fMRI (Beauchamp, Cox, DeYoe, 1997; Shulman et al., 1999; Watanabe et al., 1998) research indicate that FBA modulates activity in a number of visual locations (e.g., V1 and MT+/V5) in response to expectations with regards to the task-relevant function dimension. Paying consideration to stimulus functions across the entire visual field enhances neural activity in the cortical locations specialized to procedure those attributes (Liu et al., 2003; O'Craven et al., 1997; Schoenfeld et al., 2007).