depression

1. Reduction of the level of functioning. 2. SYN: excavation (1). 3. Displacement of a part downward or inward. 4. A temporary mental state or chronic mental disorder characterized by feelings of sadness, loneliness, despair, low self-esteem, and self-reproach; accompanying signs include psychomotor retardation or less frequently agitation, withdrawal from social contact, and vegetative states such as loss of appetite and insomnia. SYN: dejection (1), depressive reaction, depressive syndrome. [L. depressio, fr. deprimo, to press down]

- agitated d. d. with excitement and restlessness.

- anaclitic d. impairment of an infant's physical, social, and intellectual development following separation from its mother or from a mothering surrogate; characterized by listlessness, withdrawal, and anorexia.

- endogenous d. any depressive disorder occurring in the absence of external precipitants and believed to have a biologic origin. SYN: endogenomorphic d., nonreactive d..

- exogenous d. similar signs and symptoms as endogenous d. but the precipitating factors are social or environmental and outside the individual.

- involutional d. d. or psychosis first occurring in the involutional years (40 to 55 for women, 50 to 65 for men).

- lingual salivary gland d. an indentation on the lingual surface of the mandible within which a portion of the submandibular gland lies; it appears radiographically as a sharply circumscribed ovoid radiolucency between the mandibular canal and the inferior border of the posterior mandible. SYN: Stafne bone cyst, static bone cyst.

- major d. a mental disorder characterized by sustained d. of mood, anhedonia, sleep and appetite disturbances, and feelings of worthlessness, guilt, and hopelessness. Diagnostic criteria (DSM-IV) for a major depressive episode include a depressed mood, a marked reduction of interest or pleasure in virtually all activities, or both, lasting for at least 2 weeks. In addition, 3 or more of the following must be present : gain or loss of weight, increased or decreased sleep, increased or decreased level of psychomotor activity, fatigue, feelings of guilt or worthlessness, diminished ability to concentrate, and recurring thoughts of death or suicide. See endogenous d., exogenous d., bipolar disorder. SYN: clinical d., major depressive disorder.Approximately 20 million persons a year suffer depressive illness in the U.S. About 10% of men and 25% of women experience major d. at some time in their lives, and 15–30% of these commit suicide. The negative impact of this disease on the economy of the U.S. is estimated at $16 billion annually. Risk factors for d. are drug or alcohol abuse, chronic physical illness, stressful life events, social isolation, a history of physical or sexual abuse, and a family history of depressive illness. D. can be masked by substance abuse. In elderly persons it may be mistaken for senile dementia, and vice versa; the two may coexist. The disorder is believed to represent an electrochemical malfunction of the limbic system involving disturbances in the metabolism of the neurotransmitters dopamine and serotonin. In persons with familial d., the number of glial cells in the subgenual prefrontal cortex is significantly smaller than in mentally healthy persons. Treatment with psychopharmaceutical agents, including tricyclic antidepressants, selective serotonin reuptake inhibitors (SSRIs), monoamine oxidase (MAO) inhibitors, and others, effectively controls most cases of clinical d.. Cognitive psychotherapy has demonstrated some success in reversing d.. Refined methods of electroconvulsive shock therapy (ECT) have been used with increasing frequency since the 1980s, generally for cases that do not respond to other treatment. Even in severe d. the response rate with ECT is 80% or higher. This mode of therapy has a faster onset of action, causes fewer side effect s than drug therapy, and is particularly useful in elderly patients.

- nonreactive d. SYN: endogenous d..

- d. of optic disk [TA] the normally occurring d. or pit in the center of the optic disk. SYN: excavatio disci [TA], excavatio papillae, excavation of optic disk, physiologic cup, physiologic excavation.

- pacchionian depressions SYN: granular foveolae, under foveola.

- postdrive d. slowing of the heart, often with a rate-dependent blockade of AV and/or VA conduction following rapid atrial stimulation.

- pterygoid d. SYN: pterygoid fovea.

- reactive d. a psychological state occasioned directly by an intensely sad external situation (frequently loss of a loved person), relieved by the removal of the external situation ( e.g., reunion with a loved person).

- spreading d. a decrease of activity evoked by local stimulation of the cerebral cortex and spreading slowly over the whole cortex.

* * *

de·pres·sion di-'presh-ən n

1) a displacement downward or inward <\depression of the jaw>

2) an act of depressing or a state of being depressed: as

a ) (1) a state of feeling sad (2) a psychoneurotic or psychotic disorder marked esp. by sadness, inactivity, difficulty with thinking and concentration, a significant increase or decrease in appetite and time spent sleeping, feelings of dejection and hopelessness, and sometimes suicidal thoughts or an attempt to commit suicide

b) a reduction in functional activity, amount, quality, or force <\depression of autonomic function> <\depression of red blood cells>

* * *

n.

a mental state characterized by excessive sadness. Activity can be agitated and restless or slow and retarded. Behaviour is governed by pessimistic or despairing beliefs, and sleep, appetite, and concentration are disturbed. There are several causes. manic-depressive psychosis causes severe depression, a major affective disorder, in which there may be delusions of being worthless, ill, wicked, or impoverished and hallucinations of accusing voices. Loss and frustration also cause depression, which may be prolonged and disproportionate in dysthymic disorder (formerly known as depressive neurosis). (See also puerperal depression.) Treatment is with antidepressant drugs, cognitive therapy, and/or psychotherapy. Severe cases may need electroconvulsive therapy.

* * *

de·pres·sion (de-preshґən) [L. deprimere to press down] 1. a hollow or depressed area; downward or inward displacement. 2. a lowering or decrease of functional activity. 3. a mental state of depressed mood characterized by feelings of sadness, despair, and discouragement. Depression ranges from normal feelings of “the blues” through dysthymic disorder to major depressive disorder. It in many ways resembles the grief and mourning that follow bereavement; there are often feelings of low self-esteem, guilt, and self-reproach, withdrawal from interpersonal contact, and somatic symptoms such as eating and sleep disturbances. depressive adj