#Paper

Annotations

(02/02/2024, 14:18:00 )

“A well- known example is top-down attention, a powerful mechanism for selective processing of behaviorally relevant information and filtering out irrelevant stimuli.” (Zhang et al., 2014, p. 660)

Involvement of the Frontal Eye Field (FEF) enhances V4 neurons and suppressed other locations

“especially the dorsolateral pre- frontal cortex and frontal eye field (FEF) (7–13). Electrical stimulation of the FEF enhanced V4 neuron responses at the retinotopically corresponding location and suppressed responses at other locations (11” (Zhang et al., 2014, p. 661)

Enhanced V1 responses & enhanced performance in a visual discrimination through Cingulum activation

“To further test the functional influence of Cg activity, we applied optogenetic manipulations in awake mice. Cg activation enhanced V1 responses” (Zhang et al., 2014, p. 661)

“We thus tested the behavioral effect of Cg activation in mice trained to perform a visual discrimination task. Cg activation significantly improved the performance (P < 0.02 for each of 5 mice, paired t test)” (Zhang et al., 2014, p. 661)

Top-down modualtion of visual processing

“We identified a region of mouse frontal cortex that can exert spatially specific top-down modulation of visual processing, which is a hallmark of selective attention. The spatial pattern of Cg projections (Fig. 1 and fig. S1) and its powerful modulation of visual processing indicate functional similarity between mouse Cg and primate FEF (although the FEF projects primarily to higher visual areas rather than V1).” (Zhang et al., 2014, p. 663)

“SOM+ neurons strongly inhibit pyramidal neurons in response to Cg input 200 mm away. That they also mediate suppression by visual stimuli outside of the re- ceptive field (26) suggests that both bottom-up visual processing and top-down attentional modulation use a common mechanism for surround suppression (37).” (Zhang et al., 2014, p. 664)