Chronic Cannabis Users: A Model for Negative Symptoms in Schizophrenia

Not Applicable

• Conditions: Chronic Cannabis Users; Healthy Subjects
• Interventions: Procedure: Magnetoencephalograph (MEG); Behavioral: Cambridge Neuropsychological Test Automated Battery (CANTAB).

• Registration Number: NCT01382433
• Lead Sponsor: Shalvata Mental Health Center

Brief Summary

The aim of the current study is set out to find a human model for negative symptoms based on clinical observation that chronic cannabis users express negative symptoms and characterize by the same neurocognitive and electrophysiology characteristics like patient suffer from schizophrenia. Towards that end the first part of the study is set out to explore weather chronic cannabis user's express negative symptoms similar to patient suffer from schizophrenia. The second part of the study will explore the neurocognitive and electrophysiology characteristics of those cannabis users that express negative symptoms. This data will be compared to parallel data of schizophrenia patients with predominantly negative symptom.

Several lines of biological and genetic evidence support the cannabinoid hypothesis for schizophrenia. Particularly, it is most significant clinically that the possible involvement of the cannabinoid system in the neural basis for the negative symptoms. This hypothesis based on clinical findings that chronic cannabis use causes a combination of symptoms including apathy, avolition, lack of interest, passivity, and cognitive impairments, the so-called "amotivational syndrome," which resembles the core negative symptoms of schizophrenia in behavioral level as well as the brain level. Both are associated with the functions or integrity of the frontal lobe due to its role in creating self-directed behaviors, deficits in which may underlie alogia, anhedonia, and flat affect. Despite the aforementioned similarities, to date, there is no documentation for such a relationship. Recognition that chronic cannabis users share the same or similar constellation of symptoms and similar neurocognitive and electrophysiology characteristics could provide a key to develop a human model for negative symptoms and an essential tool to comprehensive understanding of the etiology of negative symptoms and development of an innovative therapy.

The investigators Hypothesize That Chronic Cannabis Users Would Express the Same Constellation of Behaviors as Negative Symptoms of Schizophrenia; as well as similar neurocognitive and electrophysiology characteristics

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2011-06-23
• Study First Submitted QC: 2011-06-24
• Study First Posted: 2011-06-27
• Study Start: 2011-07
• Status Verified: 2011-12
• Last Update Submitted: 2011-12-29
• Last Update Posted: 2012-01-02
• Primary Completion: 2012-07

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 115

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Chronic Cannabis Users	Magnetoencephalograph (MEG)	-
Chronic Cannabis Users	Cambridge Neuropsychological Test Automated Battery (CANTAB).	-
Control	Magnetoencephalograph (MEG)	Neurotypical subjects
Control	Cambridge Neuropsychological Test Automated Battery (CANTAB).	Neurotypical subjects

Primary Outcome Measures

Name	Time	Method
Clinical Measure	30 min	All participants will be assessed for negative symptoms using the Scale for the Assessment of Negative Symptoms (SANS) and the Positive and Negative Syndrome Scale (PANSS)
Cognitive Measure	1 hour	Cognitive Measure - All participants will be assessed for Cognitive function using the Cambridge Neuropsychological Test Automated Battery (CANTAB).
Electrophysiological Measure	1 hour	Electrophysiological Measure- - All participants will be assessed for Electrophysiological assesment using the MEG (Magnetoencephalogram)

Trial Locations

Locations (1)

Bar-Ilan University; 🇮🇱 Givat Shmuel, Israel