Psychological dependence is a cognitive disorder that involves emotional–motivational withdrawal symptoms—e.g.

anxiety Anxiety is an emotion which is characterized by an unpleasant state of inner turmoil and includes feelings of dread over anticipated events. Anxiety is different than fear in that the former is defined as the anticipation of a future threat wh ...

and

anhedonia Anhedonia is a diverse array of deficits in hedonic function, including reduced motivation or ability to experience pleasure. While earlier definitions emphasized the inability to experience pleasure, anhedonia is currently used by researchers ...

—upon cessation of prolonged

drug abuse Substance abuse, also known as drug abuse, is the use of a drug in amounts or by methods which are harmful to the individual or others. It is a form of substance-related disorder. Differing definitions of drug abuse are used in public health, ...

or certain repetitive

behavior Behavior (American English) or behaviour (British English) is the range of actions and mannerisms made by individuals, organisms, systems or artificial entities in some environment. These systems can include other systems or organisms as we ...

s. It develops through frequent exposure to a psychoactive substance or behavior, though behavioral dependence is less talked about. The specific mechanism involves a neuronal counter-adaption, which could be mediated through changes in neurotransmittor activity or altered receptor expression. Environmental enrichment and physical activity can attenuate withdrawal symptoms. Psychological dependence is not to be confused with

physical dependence Physical dependence is a physical condition caused by chronic use of a tolerance-forming drug, in which abrupt or gradual drug withdrawal causes unpleasant physical symptoms. Physical dependence can develop from low-dose therapeutic use of certai ...

, which induces physical withdrawal symptoms upon discontinuation of use. However, they are not mutually exclusive.

Symptoms

Symptoms of psychological dependence include: *

Anxiety Anxiety is an emotion which is characterized by an unpleasant state of inner turmoil and includes feelings of dread over anticipated events. Anxiety is different than fear in that the former is defined as the anticipation of a future threat wh ...

Panic attack Panic attacks are sudden periods of intense fear and discomfort that may include palpitations, sweating, chest pain or chest discomfort, shortness of breath, trembling, dizziness, numbness, confusion, or a feeling of impending doom or of losing ...

* Dysphoria *

Anhedonia Anhedonia is a diverse array of deficits in hedonic function, including reduced motivation or ability to experience pleasure. While earlier definitions emphasized the inability to experience pleasure, anhedonia is currently used by researchers ...

* Craving * Stress

Development

Psychological dependence is caused by consistent and frequent exposure to a drug or behavioural activity. It is often associated with effects of drug use, but it can also be caused by behavioural activity e.g. pornography. The mechanism that generates dependence involves a neuronal counter-adaption, which is localized to areas of the brain responsible for a drug's

positive reinforcement In behavioral psychology, reinforcement is a consequence applied that will strengthen an organism's future behavior whenever that behavior is preceded by a specific antecedent stimulus. This strengthening effect may be measured as a higher fr ...

. This adaption occurs as a change in neurotransmitter activity or in receptor expression. Change in neurotransmitter activity Studies have shown that in rats experiencing

ethanol withdrawal Alcohol withdrawal syndrome (AWS) is a set of symptoms that can occur following a reduction in alcohol use after a period of excessive use. Symptoms typically include anxiety, shakiness, sweating, vomiting, fast heart rate, and a mild fever. Mo ...

, stimulant withdrawal or opioid withdrawal, the

nucleus accumbens The nucleus accumbens (NAc or NAcc; also known as the accumbens nucleus, or formerly as the ''nucleus accumbens septi'', Latin for "nucleus adjacent to the septum") is a region in the basal forebrain rostral to the preoptic area of the hyp ...

shows lower levels of serotonin and dopamine than controls. These decreases are associated with depression and

. In anatomically distinct areas of the rat brain, withdrawal is linked to lower levels of GABA and

neuropeptide Y Neuropeptide Y (NPY) is a 36 amino-acid neuropeptide that is involved in various physiological and homeostatic processes in both the central and peripheral nervous systems. NPY has been identified as the most abundant peptide present in the ma ...

as well as higher levels of dynorphin,

corticotropin-releasing factor Corticotropin-releasing factor family, CRF family is a family of related neuropeptides in vertebrates. This family includes corticotropin-releasing hormone (also known as CRF), urotensin-I, urocortin, and sauvagine. The family can be grouped ...

, and

norepinephrine Norepinephrine (NE), also called noradrenaline (NA) or noradrenalin, is an organic chemical in the catecholamine family that functions in the brain and body as both a hormone and neurotransmitter. The name "noradrenaline" (from Latin '' ad ...

; these fluctuations can contribute to psychological dependence. Altered receptor expression Changes in receptor expression have also been linked to various symptoms of drug withdrawal. For example, in a study of rats undergoing nicotine withdrawal there has been observed a down regulation of α6β2*n-icotinic acetylcholine receptors in the mesostriatal dopaminergic pathways.

Methods for reducing dependence

A study examined how rats experienced morphine withdrawal in different surroundings. The rats were either placed in a standard environment (SE) or in an enriched environment (EE). The study concluded that EE reduced depression and anxiety withdrawal symptoms. Another study tested whether swimming exercises affected the intensity of perceivable psychological symptoms in rodents during morphine withdrawal. It concluded that the anxious and depressive states of the withdrawal were reduced in rats from the exercise group.

Distinction between psychological and physical dependence

{, class="wikitable" style="float: right; border: 1px solid #BBB; margin: .46em 0 0 .2em;" {, , + Table 1: List of different drugs and which type of dependence they induce !Physical dependence !Psychological dependence , - ,

Alcohols In chemistry, an alcohol is a type of organic compound that carries at least one hydroxyl () functional group bound to a saturated carbon atom. The term ''alcohol'' originally referred to the primary alcohol ethanol (ethyl alcohol), which is ...

Stimulant Stimulants (also often referred to as psychostimulants or colloquially as uppers) is an overarching term that covers many drugs including those that increase activity of the central nervous system and the body, drugs that are pleasurable and inv ...

s , - ,

Opioid Opioids are substances that act on opioid receptors to produce morphine-like effects. Medically they are primarily used for pain relief, including anesthesia. Other medical uses include suppression of diarrhea, replacement therapy for opioid use ...

s , Hallucinogens , - ,

Benzodiazepine Benzodiazepines (BZD, BDZ, BZs), sometimes called "benzos", are a class of depressant drugs whose core chemical structure is the fusion of a benzene ring and a diazepine ring. They are prescribed to treat conditions such as anxiety disorders, ...

s , Cannabis products , - ,

Barbiturate Barbiturates are a class of depressant drugs that are chemically derived from barbituric acid. They are effective when used medically as anxiolytics, hypnotics, and anticonvulsants, but have physical and psychological addiction potential a ...

s , Inhalants , - , ,

SSRIs Selective serotonin reuptake inhibitors (SSRIs) are a class of drugs that are typically used as antidepressants in the treatment of major depressive disorder, anxiety disorders, and other psychological conditions. SSRIs increase the extracellu ...

The major differences between psychological dependence and physical dependence are the symptoms they cause. While symptoms of psychological dependence relate to emotional and motivational impairment, physical dependence entails somatic symptoms e.g. increased heart rate, sweating,

tremor A tremor is an involuntary, somewhat rhythmic, muscle contraction and relaxation involving oscillations or twitching movements of one or more body parts. It is the most common of all involuntary movements and can affect the hands, arms, eyes, f ...

. The type of dependence experienced after chronic use varies between different substances (see table 1). Although psychological dependence and physical dependence are distinct entities, they should not be characterized as mutually exclusive. Empirical studies have shown that cravings, which are traditionally associated with psychological dependence, involve a physiological element.

References

{{Reflist Substance dependence Psychopathological syndromes

Symptoms

Development

Methods for reducing dependence

Distinction between psychological and physical dependence

See also

References