Final answer:
Psychological dependence is the emotional need for a substance to relieve psychological distress, differing from physical dependence that leads to withdrawal symptoms. Tolerance signifies the need for increased substance use to achieve prior effects, and rehabilitation can involve therapy and support groups.
Step-by-step explanation:
Psychological dependence is defined as an emotional, rather than physical, need for a substance, which might be used by an individual to alleviate psychological distress. This type of dependence is particularly important in the context of drug use and addiction, where a person continues to use a substance to satisfy emotional cravings, despite any negative consequences this might entail. Unlike physical dependence, which is characterized by withdrawal symptoms such as tremors or seizures, psychological dependence leads to symptoms such as anxiety, depression, or drug cravings when the substance is no longer used.
Tolerance is closely linked to physiological dependence and occurs when a person needs to consume an increasingly greater amount of a drug to achieve the same effects once attained at lower doses. It can be particularly dangerous as it may lead to overdose and potentially death. Understanding psychological dependence is crucial in the diagnosis and treatment of substance use disorders, as it has been acknowledged as a key factor in the DSM-5 diagnostic criteria for these conditions.
Rehabilitation from drug addiction and dependence often requires psychotherapy, medication, and support from organizations like Alcoholics Anonymous (AA) or Narcotics Anonymous (NA), where the primary goal is to help individuals maintain sobriety. Rehab might also utilize medications that reduce cravings and withdrawal symptoms, such as methadone in the case of heroin addiction, without creating new dependencies.