Executive functions in obsessive-compulsive disorder: An activation likelihood estimate meta-analysis of fMRI studies.

OBJECTIVES: To identify activation changes assessed in functional magnetic resonance imaging (fMRI) studies of obsessive-compulsive disorder (OCD) through Activation Likelihood Estimate meta-analysis. METHODS: We included 28 peer-reviewed standard stereotactic space studies assessing adult OCD patients (OCDpts) vs. healthy controls (HCs) with fMRI during executive task performance. RESULTS: In within-group analyses, HCs showed task-related activations in bilateral inferior frontal gyri, right middle frontal gyrus, right inferior parietal lobule, right claustrum, bilateral cingulate gyri, and left caudate body. OCDpts showed task-related left-sided activations in the superior, medial, and inferior frontal gyri, and thalamus, and bilateral activations in the middle frontal gyri, inferior parietal lobule, and insular cortices. Subtraction analysis showed increased left middle frontal gyrus activation in OCDpts. In between-groups analyses, OCDpts hypoactivated the right caudate body, left putamen, left ACC, and right medial and middle frontal gyri. Right caudate hypoactivation persisted also after applying Family-wise error algorithms. CONCLUSIONS: This meta-analysis confirms that during executive functioning OCDpts show a functional deficit of the right caudate body, which could represent a major neural functional correlate of their illness.

Pain perception and hypnosis: findings from recent functional neuroimaging studies.

Hypnosis modulates pain perception and tolerance by affecting cortical and subcortical activity in brain regions involved in these processes. By reviewing functional neuroimaging studies focusing on pain perception under hypnosis, the authors aimed to identify brain activation-deactivation patterns occurring in hypnosis-modulated pain conditions. Different changes in brain functionality occurred throughout all components of the pain network and other brain areas. The anterior cingulate cortex appears to be central in modulating pain circuitry activity under hypnosis. Most studies also showed that the neural functions of the prefrontal, insular, and somatosensory cortices are consistently modified during hypnosis-modulated pain conditions. Functional neuroimaging studies support the clinical use of hypnosis in the management of pain conditions.

Hypnosis and pain perception: An Activation Likelihood Estimation (ALE) meta-analysis of functional neuroimaging studies.

BACKGROUND AND OBJECTIVE: Several studies reported that hypnosis can modulate pain perception and tolerance by affecting cortical and subcortical activity in brain regions involved in these processes. We conducted an Activation Likelihood Estimation (ALE) meta-analysis on functional neuroimaging studies of pain perception under hypnosis to identify brain activation-deactivation patterns occurring during hypnotic suggestions aiming at pain reduction, including hypnotic analgesic, pleasant, or depersonalization suggestions (HASs). DATABASES AND DATA TREATMENT: We searched the PubMed, Embase and PsycInfo databases; we included papers published in peer-reviewed journals dealing with functional neuroimaging and hypnosis-modulated pain perception. The ALE meta-analysis encompassed data from 75 healthy volunteers reported in 8 functional neuroimaging studies. RESULTS: HASs during experimentally-induced pain compared to control conditions correlated with significant activations of the right anterior cingulate cortex (Brodmann's Area [BA] 32), left superior frontal gyrus (BA 6), and right insula, and deactivation of right midline nuclei of the thalamus. CONCLUSIONS: HASs during experimental pain impact both cortical and subcortical brain activity. The anterior cingulate, left superior frontal, and right insular cortices activation increases could induce a thalamic deactivation (top-down inhibition), which may correlate with reductions in pain intensity.

Neurocognition under hypnosis: findings from recent functional neuroimaging studies.

Functional neuroimaging studies show that hypnosis affects attention by modulating anterior cingulate cortex activation and uncoupling conflict monitoring and cognitive control function. Considering functional changes in the activation of the occipital and temporal cortices, precuneus, and other extrastriate visual areas, which account for hypnosis-induced altered reality perception, the role of mental imagery areas appears to be central under hypnosis. This is further stressed by the fact that motor commands are processed differently in the normal conscious state, deviating toward the precuneus and extrastriate visual areas. Functional neuroimaging also shows that posthypnotic suggestions alter cognitive processes. Further research should investigate the effects of hypnosis on other executive functions and personality measures.

Psychosis risk syndrome comorbid with panic attack disorder in a cannabis-abusing patient affected by Arnold-Chiari malformation type I.

OBJECTIVE: An 18-year-old man with Arnold-Chiari malformation (ACM) type I developed sudden panic attacks. He also manifested sleep disorder, cannabis abuse, and psychosis-risk syndrome (PRS). Although with average-superior intelligence, he had executive dysfunction. This prompted us to explore the relation between ACM, cannabis abuse, PRS and panic disorder. METHOD: We report the case and briefly review the literature focusing on ACM and psychiatric disorders. RESULTS: Behavior therapy led to gradual abstinence from cannabis with disappearance of anxiety symptoms. The patient is currently well and maintained on omega-3 polyunsaturated fatty acids. CONCLUSIONS: Locus coeruleus compression and cannabis abuse may have triggered the symptoms, and the latter might also be PRS-related. PRS and anxiety symptoms should be explored in ACM patients to allow better prevention of psychosis and anxiety disorders.