The Fusiform Imagery Node: Where vision meets concepts in the left temporal lobe

Abstract

We present a perspective that integrates clinical and neuroimaging evidence to argue that voluntary visual mental imagery is supported by a distributed network organized around the Fusiform Imagery Node (FIN) of the left fusiform gyrus. Lesion evidence shows that imagery is consistently impaired when the FIN is damaged or disconnected, while neuroimaging confirms robust, domain-independent activation of this cortical area. Recent 7T fMRI data further clarify the putative functional attributes of the FIN. First, the FIN appears to subserve domain-general processes, supporting imagery for objects, colors, words, faces, and spatial relationships, whereas adjacent ventral temporal regions display domain selectivity. Second, it encodes semantic information, as shown by shared multivoxel activity patterns between the FIN, the left inferior frontal gyrus, and the intraparietal sulcus, indicating common representational codes for semantic content. Third, FIN representational overlap between imagery and perception correlates with subjective vividness-the more perceptual-like the representation, the more vivid the experience. This overlap is absent in aphantasia. Fourth, the FIN exhibits functional connectivity with both frontoparietal control regions and domain-specific areas, consistent with a role as a semantic integration hub. Notably, FIN-prefrontal connectivity is markedly reduced in aphantasia. Fifth, the FIN is strongly left-lateralized, mirroring the asymmetry of the semantic system that provides a major input to imagery. Collectively, these features suggest that the FIN serves as a central bridge between semantic and visual information, essential for constructing mental images. Its connectivity may account for individual variability in imagery vividness-from aphantasia to typical imagery-and offers theoretical insight into the neural mechanisms of conscious processing and hemispheric asymmetries, with implications for both clinical and applied domains.

The Fusiform Imagery Node: Where vision meets concepts in the left temporal lobe

Abstract

We present a perspective that integrates clinical and neuroimaging evidence to argue that voluntary visual mental imagery is supported by a distributed network organized around the Fusiform Imagery Node (FIN) of the left fusiform gyrus. Lesion evidence shows that imagery is consistently impaired when the FIN is damaged or disconnected, while neuroimaging confirms robust, domain-independent activation of this cortical area. Recent 7T fMRI data further clarify the putative functional attributes of the FIN. First, the FIN appears to subserve domain-general processes, supporting imagery for objects, colors, words, faces, and spatial relationships, whereas adjacent ventral temporal regions display domain selectivity. Second, it encodes semantic information, as shown by shared multivoxel activity patterns between the FIN, the left inferior frontal gyrus, and the intraparietal sulcus, indicating common representational codes for semantic content. Third, FIN representational overlap between imagery and perception correlates with subjective vividness-the more perceptual-like the representation, the more vivid the experience. This overlap is absent in aphantasia. Fourth, the FIN exhibits functional connectivity with both frontoparietal control regions and domain-specific areas, consistent with a role as a semantic integration hub. Notably, FIN-prefrontal connectivity is markedly reduced in aphantasia. Fifth, the FIN is strongly left-lateralized, mirroring the asymmetry of the semantic system that provides a major input to imagery. Collectively, these features suggest that the FIN serves as a central bridge between semantic and visual information, essential for constructing mental images. Its connectivity may account for individual variability in imagery vividness-from aphantasia to typical imagery-and offers theoretical insight into the neural mechanisms of conscious processing and hemispheric asymmetries, with implications for both clinical and applied domains.