State Cannabis Legalization and Psychosis-Related Health Care Utilization.

Importance: Psychosis is a hypothesized consequence of cannabis use. Legalization of cannabis could therefore be associated with an increase in rates of health care utilization for psychosis.

Objective: To evaluate the association of state medical and recreational cannabis laws and commercialization with rates of psychosis-related health care utilization.

Feasibility and challenges of inpatient psychotherapy for psychosis: lessons learned from a veterans health administration pilot randomized controlled trial.

Background: In large health care systems, decision regarding broad implementation of psychotherapies for inpatients with psychosis require substantial evidence regarding effectiveness and feasibility for implementation. It is important to recognize challenges in conducting research to inform such decisions, including difficulties in obtaining consent from and engaging inpatients with psychosis in research. We set out to conduct a feasibility and effectiveness Hybrid Type I pilot randomized controlled trial of acceptance and commitment therapy (ACT) and a semi-formative evaluation of barriers and facilitators to implementation.

Out-of-synch and out-of-sorts: dysfunction of motor-sensory communication in schizophrenia.

Background: Phase synchronization of neural activity preceding a motor act may reflect an efference copy of the motor plan and its expected sensory consequences (corollary discharge), which is sent to sensory cortex to herald the arrival of self-generated sensations and dampen the resulting sensory experience. We performed time-frequency decomposition of response-locked electroencephalogram (EEG) to examine phase synchronization of oscillations across trials (phase-locking factor [PLF]) to self-paced button presses. If prepress PLF reflects the activity in motor cortex, it should be contralateralized.

Dissecting corollary discharge dysfunction in schizophrenia.

During talking, a corollary discharge prepares cortex for self-generated sounds, minimizing responsiveness and providing a way to recognize sounds as self-generated. When we talk, we are the agent producing the sound and know what sound to expect. The auditory ERP N1 is normally suppressed during talking, but less so in schizophrenia, perhaps due to deficits in agency and expectancy inherent to talking.

Relationship of imprecise corollary discharge in schizophrenia to auditory hallucinations.

Context: A forward model of intended thoughts and actions prepares sensory cortex for sensations that are a consequence of those actions. Imprecision of the corollary discharge in schizophrenia may contribute to the misperception of inner experiences and thoughts as "voices" or auditory hallucinations.

Objectives: To assess the precision of the forward model in schizophrenia using the N100 component of the auditory event-related potential to speech that is altered or unaltered, in real time, as it is being spoken.

Synch before you speak: auditory hallucinations in schizophrenia.

Objective: Synchronization of neural activity preceding self-generated actions may reflect the operation of the forward model, which acts to dampen sensations resulting from those actions. If this is true, pre-action synchrony should be related to subsequent sensory suppression. Deficits in this mechanism may be characteristic of schizophrenia and related to positive symptoms, such as auditory hallucinations.

Reduced gamma-band coherence to distorted feedback during speech when what you say is not what you hear.

Background: Communication between the frontal lobes, where speech is generated, and the temporal lobes, where it is perceived, may occur through the action of an efference copy/corollary discharge mechanism that prepares the temporal lobes for the expected sound. We suggest that coherence of EEG in gamma-band between frontal and temporal lobes may reflect the successful action of such a mechanism. We tested the hypothesis that there would be a disruption of gamma-band coherence when the expected auditory consequence of speech does not match the auditory experience.

Delayed hemodynamic responses in schizophrenia.

While there are many reports of reduced amplitude of hemodynamic responses in schizophrenia, there are no reports of delayed hemodynamic responses, in spite of event-related brain potential (ERP) evidence of slowed neural responses. Recently, Henson et al. (2002) [Henson, R.

Acquiring and inhibiting prepotent responses in schizophrenia: event-related brain potentials and functional magnetic resonance imaging.

Background: Schizophrenia is associated with deficits in using context to establish prepotent responses in complex paradigms and failures to inhibit prepotent responses once established.

Objective: To assess prepotent response establishment and inhibition in patients with schizophrenia using event-related brain potential (ERP) and functional magnetic resonance imaging (fMRI) in a simple NoGo task. To combine fMRI and ERP data to focus on fMRI activations associated with the brief (approximately 200 ms) moment of context updating reflected in the NoGo P300 ERP component.

N400 and automatic semantic processing abnormalities in patients with schizophrenia.

Background: One factor hypothesized to underlie thinking disturbance in patients with schizophrenia is abnormal or disinhibited automatic spreading activation of semantic networks, which can be assessed using the N400 event-related potential. N400 is a negative-going component elicited at about 400 milliseconds following semantic stimuli that are not primed by the preceding context. Semantic priming refers to facilitated semantic processing gained through preexposure to semantic context, which can happen automatically or strategically.

Reduced communication between frontal and temporal lobes during talking in schizophrenia.

Background: Communication between the frontal lobes, where speech and verbal thoughts are generated, and the temporal lobes, where they are perceived, may occur through the action of a corollary discharge. Its dysfunction may underlie failure to recognize inner speech as self-generated and account for auditory hallucinations in schizophrenia.

Methods: Electroencephalogram was recorded from 10 healthy adults and 12 patients with schizophrenia (DSM-IV) in two conditions: talking aloud and listening to their own played-back speech.

Response-monitoring dysfunction in schizophrenia: an event-related brain potential study.

Error-monitoring abnormalities may underlie positive symptoms of schizophrenia. Response-synchronized event-related potentials during picture-word matching yielded error- and correct-response-related negativity (ERN, CRN) and positivity (Pe, Pc) and preresponse lateralized readiness potentials (LRP) from 18 schizophrenic patients and 18 controls. Both groups responded faster to matches than nonmatches, although patients were generally slower and made more errors to nonmatches.