Biopsychosocial Model
A framework proposed by George Engel in 1977 that understands mental illness as arising from the interaction of biological factors (genetics, neurochemistry), psychological factors (thoughts, emotions, behaviors), and social factors (relationships, culture, socioeconomic status).
Example: A patient's depression may be understood as resulting from a genetic predisposition (biological), negative thought patterns (psychological), and social isolation after job loss (social), leading to a treatment plan addressing all three domains.
DSM Diagnostic Criteria
The Diagnostic and Statistical Manual of Mental Disorders (DSM), published by the American Psychiatric Association, provides standardized criteria for classifying mental disorders. The current edition, DSM-5-TR, organizes disorders into categories and specifies symptom thresholds, duration, and functional impairment requirements.
Example: To diagnose Major Depressive Disorder, a patient must exhibit at least five of nine specified symptoms nearly every day for at least two weeks, with at least one symptom being depressed mood or loss of interest.
Neurotransmitter Systems
Chemical messenger systems in the brain that are central to psychiatric understanding. Key neurotransmitters include serotonin (mood regulation), dopamine (reward and motivation), norepinephrine (arousal and alertness), GABA (inhibition and anxiety), and glutamate (excitation and cognition).
Example: The monoamine hypothesis of depression posits that deficient serotonin, norepinephrine, or dopamine activity contributes to depressive symptoms, which is why SSRIs that increase serotonin availability can alleviate depression in many patients.
Psychopharmacology
The scientific study of the effects of medications on mood, cognition, behavior, and mental states. Major drug classes include antidepressants (SSRIs, SNRIs, MAOIs), antipsychotics (typical and atypical), mood stabilizers (lithium, anticonvulsants), anxiolytics (benzodiazepines, buspirone), and stimulants.
Example: A psychiatrist prescribing lithium for bipolar disorder must monitor blood levels regularly because the therapeutic window is narrow, and toxicity can cause serious kidney and thyroid complications.
Psychotherapy Integration
The practice of combining medication management with structured psychotherapeutic approaches. Evidence-based therapies used in psychiatric practice include Cognitive Behavioral Therapy (CBT), Dialectical Behavior Therapy (DBT), psychodynamic therapy, and interpersonal therapy.
Example: For moderate-to-severe depression, guidelines recommend combining an SSRI antidepressant with CBT, as the combination has been shown to be more effective than either treatment alone.
Psychiatric Assessment
A comprehensive clinical evaluation that includes a thorough psychiatric history, mental status examination (MSE), risk assessment for suicide and violence, review of medical conditions, substance use screening, and often collateral information from family or prior records.
Example: During a mental status examination, the psychiatrist systematically evaluates the patient's appearance, behavior, speech, mood, affect, thought process, thought content, perception, cognition, insight, and judgment.
Informed Consent and Capacity
The ethical and legal requirement that patients understand and voluntarily agree to proposed treatments. Psychiatric patients must have decisional capacity, meaning the ability to understand relevant information, appreciate its significance, reason about options, and communicate a choice.
Example: A patient with schizophrenia who is experiencing active delusions may lack capacity to refuse life-saving treatment, potentially triggering involuntary treatment proceedings under mental health law.
Comorbidity
The co-occurrence of two or more psychiatric disorders, or of psychiatric and medical conditions, in the same individual. Comorbidity is the rule rather than the exception in psychiatry and significantly complicates diagnosis and treatment planning.
Example: A patient presenting with panic disorder frequently also meets criteria for major depression and may have an underlying thyroid condition, requiring the psychiatrist to develop an integrated treatment plan addressing all conditions.
