Biological psychiatry or biopsychiatry is an approach to psychiatry that aims to understand mental disorder in terms of the biological function of the nervous system. It is interdisciplinary in its approach and draws on sciences such as neuroscience, psychopharmacology, biochemistry, genetics, epigenetics and physiology to investigate the biological bases of behavior and psychopathology. Biopsychiatry is the branch of medicine which deals with the study of the biological function of the nervous system in mental disorders. [1] [2] [3]
There is some overlap with neurology, which focuses on disorders where gross or visible pathology of the nervous system is apparent, such as epilepsy, cerebral palsy, encephalitis, neuritis, Parkinson's disease and multiple sclerosis. There is also some overlap with neuropsychiatry, which typically deals with behavioral disturbances in the context of apparent brain disorder. In contrast biological psychiatry describes the basic principles and then delves deeper into various disorders. It is structured to follow the organisation of the DSM-IV, psychiatry's primary diagnostic and classification guide. The contributions of this field explore functional neuroanatomy, imaging, and neuropsychology and pharmacotherapeutic possibilities for depression, anxiety and mood disorders, substance abuse and eating disorders, schizophrenia and psychotic disorders, and cognitive and personality disorders. [4]
Biological psychiatry and other approaches to mental illness are not mutually exclusive, but may simply attempt to deal with the phenomena at different levels of explanation. Because of the focus on the biological function of the nervous system, however, biological psychiatry has been particularly important in developing and prescribing drug-based treatments for mental disorders.
In practice, however, psychiatrists may advocate both medication and psychological therapies when treating mental illness. The therapy is more likely to be conducted by clinical psychologists, psychotherapists, occupational therapists or other mental health workers who are more specialized and trained in non-drug approaches. [5] [6]
The history of the field extends back to the ancient Greek physician Hippocrates, [7] but the phrase biological psychiatry was first used in peer-reviewed scientific literature in 1953. The phrase is more commonly used in the United States than in some other countries such as the UK. [8] However the term "biological psychiatry" is sometimes used as a phrase of disparagement in controversial dispute.
Biological psychiatry is a branch of psychiatry where the focus is chiefly on researching and understanding the biological basis of major mental disorders such as unipolar and bipolar affective (mood) disorders, schizophrenia and organic mental disorders such as Alzheimer's disease. This knowledge has been gained using imaging techniques, psychopharmacology, neuroimmunochemistry and so on. Discovering the detailed interplay between neurotransmitters and the understanding of the neurotransmitter fingerprint of psychiatric drugs such as clozapine has been a helpful result of the research.
On a research level, it includes all possible biological bases of behavior — biochemical, genetic, physiological, neurological and anatomical. On a clinical level, it includes various therapies, such as drugs, diet, avoidance of environmental contaminants, exercise, and alleviation of the adverse effects of life stress, [9] all of which can cause measurable biochemical changes. [10] The biological psychiatrist views all of these as possible etiologies of or remedies for mental health disorders.
However, the biological psychiatrist typically does not discount talk therapies. Medical psychiatric training generally includes psychotherapy and biological approaches. [5] Accordingly, psychiatrists are usually comfortable with a dual approach: "psychotherapeutic methods […] are as indispensable as psychopharmacotherapy in a modern psychiatric clinic". [6]
Sigmund Freud developed psychotherapy in the early 1900s, and through the 1950s this technique was prominent in treating mental health disorders.
However, in the late 1950s, the first modern antipsychotic and antidepressant drugs were developed: chlorpromazine (also known as Thorazine), the first widely used antipsychotic, was synthesized in 1950, and iproniazid, one of the first antidepressants, was first synthesized in 1957. In 1959 imipramine, the first tricyclic antidepressant, was developed.
Based significantly on clinical observations of the above drug results, in 1965 the seminal paper "The catecholamine hypothesis of affective disorders" was published. [11] It articulated the "chemical imbalance" hypothesis of mental health disorders, especially depression. It formed much of the conceptual basis for the modern era in biological psychiatry. [12]
The hypothesis has been extensively revised since its advent in 1965. More recent research points to deeper underlying biological mechanisms as the possible basis for several mental health disorders. [13] [14] [ unreliable medical source? ]
Modern brain imaging techniques allow noninvasive examination of neural function in patients with mental health disorders, however this is currently experimental. With some disorders it appears the proper imaging equipment can reliably detect certain neurobiological problems associated with a specific disorder. [15] [16] If further studies corroborate these experimental results, future diagnosis of certain mental health disorders could be expedited using such methods.
Another source of data indicating a significant biological aspect of some mental health disorders is twin studies. Identical twins have the same nuclear DNA, so carefully constructed studies may indicate the relative importance of environmental and genetic factors on the development of a particular mental health disorder.
The results from this research and the associated hypotheses form the basis for biological psychiatry and the treatment approaches in a clinical setting.
Since various biological factors can affect mood and behavior, psychiatrists often evaluate these before initiating further treatment. For example, dysfunction of the thyroid gland may mimic a major depressive episode, or hypoglycemia (low blood sugar) may mimic psychosis.[ citation needed ]
While pharmacological treatments are used to treat many mental disorders, other non-drug biological treatments are used as well, ranging from changes in diet and exercise to transcranial magnetic stimulation and electroconvulsive therapy. Types of non-biological treatments such as cognitive therapy, behavioral therapy, and psychodynamic psychotherapy are often used in conjunction with biological therapies. Biopsychosocial models of mental illness are widely in use, and psychological and social factors play a large role in mental disorders, even those with an organic basis such as schizophrenia.
Correct diagnosis is important for mental health disorders, otherwise the condition could worsen, resulting in a negative impact on both the patient and the healthcare system. [17] Another problem with misdiagnosis is that a treatment for one condition might exacerbate other conditions. [18] [19] In other cases apparent mental health disorders could be a side effect of a serious biological problem such as concussion, [20] brain tumor, [21] [22] or hormonal abnormality, [21] [23] [24] [25] which could require medical or surgical intervention.
Sigmund Freud was originally focused on the biological causes of mental illness. Freud's professor and mentor, Ernst Wilhelm von Brücke, strongly believed that thought and behavior were determined by purely biological factors. Freud initially accepted this and was convinced that certain drugs (particularly cocaine) functioned as antidepressants. He spent many years trying to "reduce" personality to neurology, a cause he later gave up on before developing his now well-known psychoanalytic theories. [26]
Nearly 100 years ago, Harvey Cushing, the father of neurosurgery, noted that pituitary gland problems often cause mental health disorders. He wondered whether the depression and anxiety he observed in patients with pituitary disorders were caused by hormonal abnormalities, the physical tumor itself, or both. [21]
An important point in modern history of biological psychiatry was the discovery of modern antipsychotic and antidepressant drugs. Chlorpromazine (also known as Thorazine), an antipsychotic, was first synthesized in 1950. In 1952, iproniazid, a drug being trialed against tuberculosis, was serendipitously discovered to have anti-depressant effects, leading to the development of MAOIs as the first class of antidepressants. [27] In 1959 imipramine, the first tricyclic antidepressant, was developed. Research into the action of these drugs led to the first modern biological theory of mental health disorders called the catecholamine theory, later broadened to the monoamine theory, which included serotonin. These were popularly called the "chemical imbalance" theory of mental health disorders.
Starting with fluoxetine (marketed as Prozac) in 1988, a series of monoamine-based antidepressant medications belonging to the class of selective serotonin reuptake inhibitors were approved. These were no more effective than earlier antidepressants, but generally had fewer side effects. [28] Most operate on the same principle, which is modulation of monoamines (neurotransmitters) in the neuronal synapse. Some drugs modulate a single neurotransmitter (typically serotonin). Others affect multiple neurotransmitters, called dual action or multiple action drugs. They are no more effective clinically than single action versions. That most antidepressants invoke the same biochemical method of action may explain why they are each similarly effective in rough terms. Recent research indicates antidepressants often work but are less effective than previously thought. [29]
The monoamine hypothesis was compelling, especially based on apparently successful clinical results with early antidepressant drugs, but even at the time there were discrepant findings. Only a minority of patients given the serotonin-depleting drug reserpine became depressed; in fact reserpine even acted as an antidepressant in many cases. This was inconsistent with the initial monoamine theory which said depression was caused by neurotransmitter deficiency.
Another problem was the time lag between antidepressant biological action and therapeutic benefit. Studies showed the neurotransmitter changes occurred within hours, yet therapeutic benefit took weeks.
To explain these behaviors, more recent modifications of the monoamine theory describe a synaptic adaptation process which takes place over several weeks. Yet this alone does not appear to explain all of the therapeutic effects. [30]
This article or section possibly contains synthesis of material which does not verifiably mention or relate to the main topic.(July 2012) |
New research indicates different biological mechanisms may underlie some mental health disorders, only indirectly related to neurotransmitters and the monoamine chemical imbalance hypothesis. [14] [ unreliable medical source? ]
Recent research indicates a biological "final common pathway" may exist which both electroconvulsive therapy [31] and most current antidepressant drugs have in common. These investigations show recurrent depression may be a neurodegenerative disorder, disrupting the structure and function of brain cells, destroying nerve cell connections, even killing certain brain cells, and precipitating a decline in overall cognitive function. [14] [ unreliable medical source? ]
In this new biological psychiatry viewpoint, neuronal plasticity is a key element. Increasing evidence points to various mental health disorders as a neurophysiological problem which inhibits neuronal plasticity. [32] [33] [34]
This is called the neurogenic hypothesis of depression. It promises to explain pharmacological antidepressant action, [13] [35] including the time lag from taking the drug to therapeutic onset, why downregulation (not just upregulation) of neurotransmitters can help depression, why stress often precipitates mood disorders, [36] and why selective modulation of different neurotransmitters can help depression. It may also explain the neurobiological mechanism of other non-drug effects on mood, including exercise, diet and metabolism. [37] By identifying the neurobiological "final common pathway" into which most antidepressants funnel, it may allow rational design of new medications which target only that pathway. This could yield drugs which have fewer side effects, are more effective and have quicker therapeutic onset. [14] [ unreliable medical source? ]
There is significant evidence that oxidative stress plays a role in schizophrenia. [38]
A number of patients, activists, and psychiatrists dispute biological psychiatry as a scientific concept or as having a proper empirical basis, for example arguing that there are no known biomarkers for recognized psychiatric conditions. This position has been represented in academic journals such as The Journal of Mind and Behavior [39] and Ethical Human Psychology and Psychiatry, which publishes material specifically countering "the idea that emotional distress is due to an underlying organic disease." [40] Alternative theories and models instead view mental disorders as non-biomedical and might explain it in terms of, for example, emotional reactions to negative life circumstances or to acute trauma. [41]
Fields such as social psychiatry, clinical psychology, and sociology may offer non-biomedical accounts of mental distress and disorder for certain ailments and are sometimes critical of biopsychiatry. Social critics believe biopsychiatry fails to satisfy the scientific method because they believe there is no testable biological evidence of mental disorders. Thus, these critics view biological psychiatry as a pseudoscience attempting to portray psychiatry as a biological science.
R.D. Laing argued that attributing mental disorders to biophysical factors was often flawed due to the diagnostic procedure. The "complaint" is often made by a family member, not the patient, the "history" provided by someone other than patient, and the "examination" consists of observing strange, incomprehensible behavior. Ancillary tests (EEG, PET) are often done after diagnosis, when treatment has begun, which makes the tests non-blind and incurs possible confirmation bias. The psychiatrist Thomas Szasz commented frequently on the limitations of the medical approach to psychiatry and argued that mental illnesses are medicalized problems in living.
Silvano Arieti, while approving of the use of medication in some cases of schizophrenia, preferred intensive psychotherapy without medication if possible. He was also known for approving the use of electroconvulsive therapy on those with disorganized schizophrenia in order to make them reachable by psychotherapy. The views he expressed in Interpretation of Schizophrenia are nowadays known as the trauma model of mental disorders, an alternative to the biopsychiatric model. [41]
Antidepressants are a class of medications used to treat major depressive disorder, anxiety disorders, chronic pain, and addiction.
Major depressive disorder (MDD), also known as clinical depression, is a mental disorder characterized by at least two weeks of pervasive low mood, low self-esteem, and loss of interest or pleasure in normally enjoyable activities. Introduced by a group of US clinicians in the mid-1970s, the term was adopted by the American Psychiatric Association for this symptom cluster under mood disorders in the 1980 version of the Diagnostic and Statistical Manual of Mental Disorders (DSM-III), and has become widely used since.
Psychopharmacology is the scientific study of the effects drugs have on mood, sensation, thinking, behavior, judgment and evaluation, and memory. It is distinguished from neuropsychopharmacology, which emphasizes the correlation between drug-induced changes in the functioning of cells in the nervous system and changes in consciousness and behavior.
A psychiatric or psychotropic medication is a psychoactive drug taken to exert an effect on the chemical makeup of the brain and nervous system. Thus, these medications are used to treat mental illnesses. These medications are typically made of synthetic chemical compounds and are usually prescribed in psychiatric settings, potentially involuntarily during commitment. Since the mid-20th century, such medications have been leading treatments for a broad range of mental disorders and have decreased the need for long-term hospitalization, thereby lowering the cost of mental health care. The recidivism or rehospitalization of the mentally ill is at a high rate in many countries, and the reasons for the relapses are under research.
Treatment-resistant depression is a term used in psychiatry to describe people with major depressive disorder (MDD) who do not respond adequately to a course of appropriate antidepressant medication within a certain time. Definitions of treatment-resistant depression vary, and they do not include a resistance to psychological therapies. Inadequate response has most commonly been defined as less than 50% reduction in depressive symptoms following treatment with at least one antidepressant medication, although definitions vary widely. Some other factors that may contribute to inadequate treatment are: a history of repeated or severe adverse childhood experiences, early discontinuation of treatment, insufficient dosage of medication, patient noncompliance, misdiagnosis, cognitive impairment, low income and other socio-economic variables, and concurrent medical conditions, including comorbid psychiatric disorders. Cases of treatment-resistant depression may also be referred to by which medications people with treatment-resistant depression are resistant to. In treatment-resistant depression adding further treatments such as psychotherapy, lithium, or aripiprazole is weakly supported as of 2019.
A major depressive episode (MDE) is a period characterized by symptoms of major depressive disorder. Those affected primarily exhibit a depressive mood for at least two weeks or more, and a loss of interest or pleasure in everyday activities. Other symptoms can include feelings of emptiness, hopelessness, anxiety, worthlessness, guilt, irritability, changes in appetite, difficulties in concentration, difficulties remembering details, making decisions, and thoughts of suicide. Insomnia or hypersomnia and aches, pains, or digestive problems that are resistant to treatment may also be present.
Mental disorders are classified as a psychological condition marked primarily by sufficient disorganization of personality, mind, and emotions to seriously impair the normal psychological and often social functioning of the individual. Individuals diagnosed with certain mental disorders can be unable to function normally in society. Mental disorders may consist of several affective, behavioral, cognitive and perceptual components. The acknowledgement and understanding of mental health conditions has changed over time and across cultures. There are still variations in the definition, classification, and treatment of mental disorders.
The biopsychiatry controversy is a dispute over which viewpoint should predominate and form a basis of psychiatric theory and practice. The debate is a criticism of a claimed strict biological view of psychiatric thinking. Its critics include disparate groups such as the antipsychiatry movement and some academics.
In applied psychology, interventions are actions performed to bring about change in people. A wide range of intervention strategies exist and they are directed towards various types of issues. Most generally, it means any activities used to modify behavior, emotional state, or feelings. Psychological interventions have many different applications and the most common use is for the treatment of mental disorders, most commonly using psychotherapy. The ultimate goal behind these interventions is not only to alleviate symptoms but also to target the root cause of mental disorders.
A serotonin–norepinephrine–dopamine reuptake inhibitor (SNDRI), also known as a triple reuptake inhibitor (TRI), is a type of drug that acts as a combined reuptake inhibitor of the monoamine neurotransmitters serotonin, norepinephrine, and dopamine. It does this by concomitantly inhibiting the serotonin transporter (SERT), norepinephrine transporter (NET), and dopamine transporter (DAT), respectively. Inhibition of the reuptake of these neurotransmitters increases their extracellular concentrations and, therefore, results in an increase in serotonergic, adrenergic, and dopaminergic neurotransmission. The naturally-occurring and potent SNDRI cocaine is widely used recreationally and often illegally for the euphoric effects it produces.
Management of depression is the treatment of depression that may involve a number of different therapies: medications, behavior therapy, psychotherapy, and medical devices.
Major depressive disorder, often simply referred to as depression, is a mental disorder characterized by prolonged unhappiness or irritability. It is accompanied by a constellation of somatic and cognitive signs and symptoms such as fatigue, apathy, sleep problems, loss of appetite, loss of engagement, low self-regard/worthlessness, difficulty concentrating or indecisiveness, or recurrent thoughts of death or suicide.
Late-life depression refers to depression occurring in older adults and has diverse presentations, including as a recurrence of early-onset depression, a new diagnosis of late-onset depression, and a mood disorder resulting from a separate medical condition, substance use, or medication regimen. Research regarding late-life depression often focuses on late-onset depression, which is defined as a major depressive episode occurring for the first time in an older person.
The psychopharmacology revolution covers the introduction of various psychiatric drugs into clinical practice as well as their continued development. Although not exclusively limited to the 1950s period, the literature tends to suggest that this decade was a particularly fruitful time for CNS drug discovery and it has been referred to as a "golden era".
The following outline is provided as an overview of and topical guide to psychiatry:
Schizophrenia is a primary psychotic disorder, whereas, bipolar disorder is a primary mood disorder which can also involve psychosis. Both schizophrenia and bipolar disorder are characterized as critical psychiatric disorders in the Diagnostic and Statistical Manual of Mental Disorders fifth edition (DSM-5). However, because of some similar symptoms, differentiating between the two can sometimes be difficult; indeed, there is an intermediate diagnosis termed schizoaffective disorder.
The pharmacology of antidepressants is not entirely clear. The earliest and probably most widely accepted scientific theory of antidepressant action is the monoamine hypothesis, which states that depression is due to an imbalance of the monoamine neurotransmitters. It was originally proposed based on the observation that certain hydrazine anti-tuberculosis agents produce antidepressant effects, which was later linked to their inhibitory effects on monoamine oxidase, the enzyme that catalyses the breakdown of the monoamine neurotransmitters. All currently marketed antidepressants have the monoamine hypothesis as their theoretical basis, with the possible exception of agomelatine which acts on a dual melatonergic-serotonergic pathway. Despite the success of the monoamine hypothesis it has a number of limitations: for one, all monoaminergic antidepressants have a delayed onset of action of at least a week; and secondly, there are a sizeable portion (>40%) of depressed patients that do not adequately respond to monoaminergic antidepressants. Further evidence to the contrary of the monoamine hypothesis are the recent findings that a single intravenous infusion with ketamine, an antagonist of the NMDA receptor — a type of glutamate receptor — produces rapid, robust and sustained antidepressant effects. Monoamine precursor depletion also fails to alter mood. To overcome these flaws with the monoamine hypothesis a number of alternative hypotheses have been proposed, including the glutamate, neurogenic, epigenetic, cortisol hypersecretion and inflammatory hypotheses. Another hypothesis that has been proposed which would explain the delay is the hypothesis that monoamines don't directly influence mood, but influence emotional perception biases.
Joanna Moncrieff is a British psychiatrist and academic. She is Professor of Critical and Social Psychiatry at University College London and a leading figure in the Critical Psychiatry Network. She is a prominent critic of the modern 'psychopharmacological' model of mental disorder and drug treatment, and the role of the pharmaceutical industry. She has written papers, books and blogs on the use and over-use of drug treatment for mental health problems, the mechanism of action of psychiatric drugs, their subjective and psychoactive effects, the history of drug treatment, and the evidence for its benefits and harms. She also writes on the history and politics of psychiatry more generally. Her best known books are The Myth of the Chemical Cure and The Bitterest Pills.
Psychiatry is, and has historically been, viewed as controversial by those under its care, as well as sociologists and psychiatrists themselves. There are a variety of reasons cited for this controversy, including the subjectivity of diagnosis, the use of diagnosis and treatment for social and political control including detaining citizens and treating them without consent, the side effects of treatments such as electroconvulsive therapy, antipsychotics and historical procedures like the lobotomy and other forms of psychosurgery or insulin shock therapy, and the history of racism within the profession in the United States.
Electroconvulsive therapy (ECT) is a controversial therapy used to treat certain mental illnesses such as major depressive disorder, schizophrenia, depressed bipolar disorder, manic excitement, and catatonia. These disorders are difficult to live with and often very difficult to treat, leaving individuals suffering for long periods of time. In general, ECT is not looked at as a first line approach to treating a mental disorder, but rather a last resort treatment when medications such as antidepressants are not helpful in reducing the clinical manifestations.