No abstract

The ventral visual pathway is well known to be involved in recognizing and categorizing objects (Kanwisher and Dilks, 2013). Three color-biased areas have also been found between face and place selective areas in the ventral visual pathway (Lafer-Sousa et al., 2016). To understand the function of these color-biased areas in a region known for object recognition, we analyzed the Natural Scenes Dataset (NSD; Allen et al., 2022), a large 7T fMRI dataset from 8 participants who viewed up to 30,000 trials of images of colored natural scenes. In a whole-brain analysis, we correlated the average color saturation of the images and the voxel responses, revealing color-biased areas that diverge into two streams in the ventral visual pathway, beginning in V4 and extending medially and laterally of the Fusiform Face Area in both hemispheres. We drew regions of interest (ROIs) for the two streams and found that the images for each ROI that evoked the largest responses had certain characteristics: They contained food, contained circular objects, had higher color saturation, contained warmer hues, and had more luminance entropy. A multiple linear regression showed that the presence of food in images was the strongest predictor of voxel responses in the medial and lateral color-biased regions for all eight participants, but that color saturation also contributed independently to voxel responses. Our results show that these areas are food-selective and color biased. We suggest that these streams might be involved in using color to recognize and judge the properties of food.

Both animal and human studies on numerosity have shown the importance of the parietal cortex for numerosity processing. However, most studies have focused on the perceptual processing of numerosity. Still, it is unclear how and where numerosity information is coded when this information is retained during a working memory delay phase. Such temporal storage could be realized by the same structures as perceptual processes, or be transformed to a more abstract representation, potentially involving prefrontal regions. FMRI decoding studies allow the identification of brain areas that exhibit multi‐voxel activation patterns specific to the content of working memory. Here, we used an assumption‐free searchlight‐decoding approach to test where numerosity‐specific codes can be found during a 12 s retention period. Participants (n = 24) performed a retro‐cue delayed match‐to‐sample task, in which numerosity information was presented as visual dot arrays. We found mnemonic numerosity‐specific activation in the right lateral portion of the intraparietal sulcus; an area well‐known for perceptual processing of numerosity. The applied retro‐cue design dissociated working memory delay activity from perceptual processes and showed that the intraparietal sulcus also maintained working memory representation independent of perception.