In several brain imaging studies performed during attacks, though not in all, [49, 50] the vascular and metabolic changes accompanying the migraine aura spread more anteriorly in patients with complex neurological symptoms and hemiplegia than in those with only visual disturbances.
Several brain imaging studies have also been conducted to assess modifications in cerebral activity following EMDR treatment, some of them are briefly presented below.
The insula activation we identified during the prickling sensation corresponds closely with the insula activation found in several brain imaging studies during the presentation of unpleasant stimuli (e.g. pain [38], or disgust [39; 40]).
Several brain-imaging studies have reported changes in regional brain morphology in visual association cortices in individuals learning how to juggle a three-ball cascade.
Dr. Nora Volkow, director of the National Institute on Drug Abuse, has shown in several brain-imaging studies that people addicted to such drugs as cocaine, heroin and alcohol have fewer dopamine receptors in the brain's reward pathways than nonaddicts.
In depression, the default mode network also appears to be overactive: Several brain-scan studies have shown a pattern in depression of balky transitions from introspective thought to work that requires conscious effort and frequent slippage into the default mode during cognitive tasks.
Further, neuroimaging studies have demonstrated structural differences and deficits in the activation of several brain areas, and studies using neurophysiology have suggested a disturbed neuronal inhibition within individuals with ADHD [ 2, 8– 11].
Ultimately, it may be this development of "gut sense" (which several early stage brain studies focusing on the insular cortex suggest may be facilitated by mindfulness practice that will help us as we inevitably, each one of us, have to face situations where a medical therapy or behavioral practice is offered in the context of real scientific uncertainty.
Several brain imaging (fMRI) studies [4], [5] suggest that perceptual persistence of motion-defined forms, post motion offset, are related to activations in brain regions along the ventral visual pathway, which are involved in object perception [e.g. 24,25,26].
