Courtesy of Godoy Medical Forensics
Early or heavy substance use can have a profound impact on an individual’s brain, with resulting changes in judgment and behavior. Substances can lead to acute impairment during periods of intoxication and withdrawal. Some substances (i.e. stimulants, PCP, etc.) induce a psychotic state during and shortly after use. These substances can mimic schizophrenia with delusions, hallucinations and bizarre behavior.
Recently, the longer term effects of substance use have become clearer. Stimulants, such as methamphetamine, are neurotoxic and harm or kill brain cells. The brain areas most affected are the areas that manage “executive functions” (judgment, impulse control, planning, and organization). Although many of the deficits from long-term substance use improve over a few years of treatment and recovery, these deficits often play a role in the behavior at the time of arrest.
Significant substance use problems are linked to early life adversity (See our post on Life Experiences). Other risk factors established by scientists include genetics, early exposure, and type of environment a person grows up in.