cannabis addiction is a major health hazard that has its effect on personality and behavior including the impulsivity and emotional regulation. It also has its effect on both the structure and function of different brain regions involved in brain reward system.

the aim of the study is to study the emotional regulation and impulsivity among people with cannabis addiction studying the change in the volume of brain reward system structures' volume in relation to cannabis addiction and the change in the mentioned behavioral traits.

Introduction:

Cannabis sativa is a widely used drug comprising a broad spectrum of usage ranging from recreational users to chronic addicts.

Dependence on cannabis is considered a major global health related issue. Cannabis is still considered the most used psychoactive substance worldwide with an estimated 2.8-5.1 % of global adult population has used cannabis in 2019.

Epidemiological studies show that cannabis is the leading drug of abuse in Egypt and in Upper Egypt. Prevalence of cannabis dependence is estimated to be 7.4% in Egypt and 6.66 % in Upper Egypt.

Cannabis dependence is associated with multiple neurobehavioral abnormalities which can be considered as a psychological determinants of cannabis dependence .

There is an increasing evidence of association between emotional dysregulation and dependence on different substances of abuse. Such dysregulation affects both components of emotional regulation; reappraisal and suppression of emotions' expression. The pattern of this dysregulation differs according to the type of substance of dependence and can affect the pattern of substance abuse.

Impulsivity is a proposed endophenotype for substance dependence as well as a possible consequence of prolonged drug use. Drugs of addiction and subconscious craving are likely to increase impulsiveness due to the loss of frontal cortical inhibition of impulses and increased limbic drive. Cannabis use may lead to a loss of attention, reflection and inhibitory control.

Materials and Methods:

This cross-sectional study ran between at the addiction management unit, Assiut University, Egypt. Two groups of participants were recruited in the study: Group (A): 32 patients with cannabis used disorder diagnosed according to DSM-5 criteria recruited from the addiction outpatient clinic at the Hospital of Neurology and Psychiatry at Assiut University. Group (B): 34 healthy individuals as a cross matching control group.

Inclusion criteria were age above 18 years, current chronic cannabis dependence. Exclusion criteria were being in withdrawal state, other psychiatric disorders, and history or current neurological or medical disease.

Ethical considerations:

A signed, informed consent was obtained from patients and their families or caregivers to participate in the study. Confidentiality was maintained during the whole study.

Assessment tools:

All participants were first assessed through a semi-structured interview using the Structured clinical interviews for axis I diagnosis (SCID-I) to rule out any psychiatric comorbidities.

Emotion Regulation Questionnaire (ERQ): A 10-item scale designed to measure respondents' tendency to regulate their emotions in two ways: (1) Cognitive Reappraisal and (2) Expressive Suppression. Respondents answer each item on a 7-point Likert-type scale.

UPPS-P Impulsive Behavior Scale- Short form: The UPPS-P impulsivity scale is a 20-item scale designed to assess five distinct personality traits to impulsive behavior: Negative Urgency, Lack of Perseverance, Lack of Premeditation, Positive Urgency and Sensation Seeking.

Magnetic resonance imaging examination:

The MR examination of brain was done using 1.5T MR scanner (Achieva, Philips Medical Systems, The Netherlands) with a 16 channel head coil without using any sedation.

Inclusion Criteria:

• Age above 18 years.
• Clearly consenting to participate in the study. . patient with substance use disorder

Exclusion Criteria:

• Intoxication or withdrawal state.
• Comorbid Axis I psychiatric disorder.
• any current or past neurological disorder.

66 participants with cannabis use disorder diagnosed by DSM-5 criteria were recruited from addiction unit at Assiut University hospitals