[7] Neurological evidence has shown that in the creation of imagery, neural activity spans prefrontal, parietal, temporal and visual areas.
[9] 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.
[6][12] 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.
[8] 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.
[8] Neuroimaging studies using functional magnetic resonance imaging (fMRI) have additionally demonstrated that hyperphantasics have significantly stronger connectivity between their prefrontal cortices (Brodmann's Areas 9, 10, 11 in particular) and their visual cortex in comparison to aphantasics.
[10] 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.
This entails more openness to "new experiences, broad interests, an active imagination and a likelihood of experiencing more positive and negative emotions more keenly than other people".
Hyperphantasics are significantly more likely to work in traditionally creative roles within "Arts, Design, Entertainment, Sports, and Media" in comparison to their aphantasic counterparts.
[6] The vividness of mental imagery has a key role in the development and continuation of intrusive memories, so for those with PTSD, having hyperphantasia is a substantial risk factor.