There is no unique mental imagery cortical network; the formation of mental imagery involves many regions of the brain, as mental imagery shares many common brain regions with other cognitive functions. Neurological evidence has shown that in the creation of imagery, neural activity spans prefrontal, parietal, temporal and visual areas. Within the neuroscience of imagery, it is often split into three primary aspects: the triggering of imagery, its generation/manipulation, and the underlying vividness of the imagery. The mechanism underlying the vividness of imagery which may explain disorders like<unk>  is controversial amongst the literature. The current findings of the mechanism of<unk>  are related to two regions of the brain: the early visual cortex and the frontal cortex. Recent research has shown the relationship between the size (surface area) of the early visual cortex (V1-V3), specifically V1 and to a lesser degree V2 (but not V3), negatively predicts imagery strength within individuals. This relationship is evidenced across both clinical and non-clinical populations see below. In contrast, there is a positive relationship between the surface area of the frontal cortex and visual imagery strength. This aligns with the reciprocal relationship between the size of primary visual cortices and frontal cortices, with a smaller V1 correlating to a larger frontal cortex. Within the general principle of human cortical organization, there is an anatomical trade-off between primary sensory cortices such as the primary visual cortex and frontal areas. Several lines of evidence suggest that the respective sizes of these areas within individuals predict their vividness of imagery. Additionally, genetics play a part in determining the surface area of V1, suggesting that genetics may indirectly contribute to<unk> . Beyond the size of these regions, there is evidence that lower resting activity and excitability levels within the primary visual cortex predicts stronger mental imagery and vice versa. This has been confirmed by artificially lowering the excitability of the visual cortex, which subsequently led to increased imagery strength. The relationship between the frontal lobe and the visual cortex form an ‘imagery network’ where the ratio in size and excitability of these two areas relate to imagery strength amongst individuals. Neuroimaging studies using functional magnetic resonance imaging (fMRI) have additionally demonstrated that<unk> cs have significantly stronger connectivity between their prefrontal cortices (Brodmann's Areas 9, 10, 11 in particular) and their visual cortex in comparison to aphantasiacs. The mechanism behind vivid imagery appears to come down to the size and excitability of the visual-occipital network and the frontal areas as well as the strength of connectivity between these brain regions. However, these factors can only explain the variations in mental imagery; the specific mechanisms that cause<unk>  are still not well documented.
Hyperphantasia
Acrodynia
Palilalia
Hypoglossia
Hypophonia
Latrodectism
Tourettism
Misophonia