Biological psychiatry
Encyclopedia
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
and physiology
to investigate the biological bases of behavior
and psychopathology
. Biopsychiatry is that branch/speciality of medicine which deals with the study of biological function of the nervous system in mental disorders.
While there is some overlap between biological psychiatry and neurology
, the latter generally 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 some overlap with neuropsychiatry
, which typically deals with behavioral disturbances in the context of apparent brain disorder.
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 therapist
s or other mental health workers who are more specialized and trained in non-drug approaches.
The history of the field extends back to the ancient Greek physician Hippocrates
, but the term biological psychiatry was first used in peer-reviewed scientific literature in 1953. The term is more commonly used in the US than in some other countries such as the UK. The field, however, is not without its critics and the phrase "biological psychiatry" is sometimes used by those critics as a term of disparagement.
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, all of which can cause measurable biochemical changes. 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 psychoanalytic approaches (talk therapies). Medical psychiatric training generally includes both psychodynamic and biological approaches. Accordingly, psychiatrists are usually comfortable with a dual approach: "psychotherapeutic methods...are as indispensable as psychopharmacotherapy in a modern psychiatric clinic."
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. 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.
The hypothesis has been extensively revised since its advent in 1965. More recent research points to deeper underlying biological mechansisms as the possible basis for several mental health disorders.
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. 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.
, or hypoglycemia
(low blood sugar) may mimic psychosis
.
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
.
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.
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.
and antidepressant
drugs. Chlorpromazine
(also known as Thorazine), an antipsychotic, was first synthesized in 1950, and iproniazid
, one of the first antidepressants, was first synthesized in 1957. 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.
(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. 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 somewhat less effective than previously thought.
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.
Recent research indicates a biological "final common pathway" may exist which both electroconvulsive therapy
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.
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.
This is called the neurogenic hypothesis of depression. It promises to explain pharmacological antidepressant action, 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, 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. 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.
for recognized psychiatric conditions. This position has been represented in niche academic journals such as The Journal of Mind and Behavior and Ethical Human Psychology and Psychiatry, which publishes material specifically countering "the idea that emotional distress is due to an underlying organic disease." 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.
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
.
Psychiatry
Psychiatry is the medical specialty devoted to the study and treatment of mental disorders. These mental disorders include various affective, behavioural, cognitive and perceptual abnormalities...
that aims to understand mental disorder in terms of the biological
Biology
Biology is a natural science concerned with the study of life and living organisms, including their structure, function, growth, origin, evolution, distribution, and taxonomy. Biology is a vast subject containing many subdivisions, topics, and disciplines...
function of the nervous system
Nervous system
The nervous system is an organ system containing a network of specialized cells called neurons that coordinate the actions of an animal and transmit signals between different parts of its body. In most animals the nervous system consists of two parts, central and peripheral. The central nervous...
. It is interdisciplinary in its approach and draws on sciences such as neuroscience
Neuroscience
Neuroscience is the scientific study of the nervous system. Traditionally, neuroscience has been seen as a branch of biology. However, it is currently an interdisciplinary science that collaborates with other fields such as chemistry, computer science, engineering, linguistics, mathematics,...
, psychopharmacology
Psychopharmacology
Psychopharmacology is the scientific study of the actions of drugs and their effects on mood, sensation, thinking, and behavior...
, biochemistry
Biochemistry
Biochemistry, sometimes called biological chemistry, is the study of chemical processes in living organisms, including, but not limited to, living matter. Biochemistry governs all living organisms and living processes...
, genetics
Genetics
Genetics , a discipline of biology, is the science of genes, heredity, and variation in living organisms....
and physiology
Physiology
Physiology is the science of the function of living systems. This includes how organisms, organ systems, organs, cells, and bio-molecules carry out the chemical or physical functions that exist in a living system. The highest honor awarded in physiology is the Nobel Prize in Physiology or...
to investigate the biological bases of behavior
Behavior
Behavior or behaviour refers to the actions and mannerisms made by organisms, systems, or artificial entities in conjunction with its environment, which includes the other systems or organisms around as well as the physical environment...
and psychopathology
Psychopathology
Psychopathology is the study of mental illness, mental distress, and abnormal/maladaptive behavior. The term is most commonly used within psychiatry where pathology refers to disease processes...
. Biopsychiatry is that branch/speciality of medicine which deals with the study of biological function of the nervous system in mental disorders.
While there is some overlap between biological psychiatry and neurology
Neurology
Neurology is a medical specialty dealing with disorders of the nervous system. Specifically, it deals with the diagnosis and treatment of all categories of disease involving the central, peripheral, and autonomic nervous systems, including their coverings, blood vessels, and all effector tissue,...
, the latter generally focuses on disorders where gross or visible pathology of the nervous system is apparent, such as epilepsy
Epilepsy
Epilepsy is a common chronic neurological disorder characterized by seizures. These seizures are transient signs and/or symptoms of abnormal, excessive or hypersynchronous neuronal activity in the brain.About 50 million people worldwide have epilepsy, and nearly two out of every three new cases...
, cerebral palsy
Cerebral palsy
Cerebral palsy is an umbrella term encompassing a group of non-progressive, non-contagious motor conditions that cause physical disability in human development, chiefly in the various areas of body movement....
, encephalitis
Encephalitis
Encephalitis is an acute inflammation of the brain. Encephalitis with meningitis is known as meningoencephalitis. Symptoms include headache, fever, confusion, drowsiness, and fatigue...
, neuritis, Parkinson's disease
Parkinson's disease
Parkinson's disease is a degenerative disorder of the central nervous system...
and multiple sclerosis
Multiple sclerosis
Multiple sclerosis is an inflammatory disease in which the fatty myelin sheaths around the axons of the brain and spinal cord are damaged, leading to demyelination and scarring as well as a broad spectrum of signs and symptoms...
. There is some overlap with neuropsychiatry
Neuropsychiatry
Neuropsychiatry is the branch of medicine dealing with mental disorders attributable to diseases of the nervous system. It preceded the current disciplines of psychiatry and neurology, in as much as psychiatrists and neurologists had a common training....
, which typically deals with behavioral disturbances in the context of apparent brain disorder.
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 therapist
Occupational therapist
An occupational therapist is trained in the practice of occupational therapy. The role of an occupational therapist is to work with a client to help them achieve a fulfilled and satisfied state in life through the use of "purposeful activity or interventions designed to achieve functional...
s or other mental health workers who are more specialized and trained in non-drug approaches.
The history of the field extends back to the ancient Greek physician Hippocrates
Hippocrates
Hippocrates of Cos or Hippokrates of Kos was an ancient Greek physician of the Age of Pericles , and is considered one of the most outstanding figures in the history of medicine...
, but the term biological psychiatry was first used in peer-reviewed scientific literature in 1953. The term is more commonly used in the US than in some other countries such as the UK. The field, however, is not without its critics and the phrase "biological psychiatry" is sometimes used by those critics as a term of disparagement.
Scope and detailed definition
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 Alzheimers 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 clozapineClozapine
Clozapine is an antipsychotic medication used in the treatment of schizophrenia, and is also used off-label in the treatment of bipolar disorder. Wyatt. R and Chew...
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, all of which can cause measurable biochemical changes. The biological psychiatrist views all of these as possible etiologies
Etiology
Etiology is the study of causation, or origination. The word is derived from the Greek , aitiologia, "giving a reason for" ....
of or remedies for mental health disorders.
However, the biological psychiatrist typically does not discount psychoanalytic approaches (talk therapies). Medical psychiatric training generally includes both psychodynamic and biological approaches. Accordingly, psychiatrists are usually comfortable with a dual approach: "psychotherapeutic methods...are as indispensable as psychopharmacotherapy in a modern psychiatric clinic."
Basis for biological psychiatry
Sigmund FreudSigmund Freud
Sigmund Freud , born Sigismund Schlomo Freud , was an Austrian neurologist who founded the discipline of psychoanalysis...
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
Antipsychotic
An antipsychotic is a tranquilizing psychiatric medication primarily used to manage psychosis , particularly in schizophrenia and bipolar disorder. A first generation of antipsychotics, known as typical antipsychotics, was discovered in the 1950s...
and antidepressant
Antidepressant
An antidepressant is a psychiatric medication used to alleviate mood disorders, such as major depression and dysthymia and anxiety disorders such as social anxiety disorder. According to Gelder, Mayou &*Geddes people with a depressive illness will experience a therapeutic effect to their mood;...
drugs were developed: chlorpromazine
Chlorpromazine
Chlorpromazine is a typical antipsychotic...
(also known as Thorazine), the first widely-used antipsychotic, was synthesized in 1950, and iproniazid
Iproniazid
Iproniazid is a hydrazine drug used as an antidepressant. It acts as an irreversible and nonselective monoamine oxidase inhibitor . Though it has been widely discontinued in most of the world, it is still used in France.- History :Iproniazid was the first antidepressant ever marketed...
, one of the first antidepressants, was first synthesized in 1957. In 1959 imipramine
Imipramine
Imipramine , also known as melipramine, is an antidepressant medication, a tricyclic antidepressant of the dibenzazepine group...
, the first tricyclic antidepressant
Tricyclic antidepressant
Tricyclic antidepressants are heterocyclic chemical compounds used primarily as antidepressants. The TCAs were first discovered in the early 1950s and were subsequently introduced later in the decade; they are named after their chemical structure, which contains three rings of atoms...
, 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. It articulated the "chemical imbalance
Chemical imbalance
Chemical imbalance is one hypothesis about the cause of mental illness. Other causes that are debated include psychological and social causes....
" hypothesis of mental health disorders, especially depression. It formed much of the conceptual basis for the modern era in biological psychiatry.
The hypothesis has been extensively revised since its advent in 1965. More recent research points to deeper underlying biological mechansisms as the possible basis for several mental health disorders.
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. 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.
Scope of clinical biological psychiatric treatment
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 episodeMajor depressive episode
A major depressive episode is the cluster of symptoms of major depressive disorder. The description has been formalised in psychiatric diagnostic criteria such as the DSM-IV and ICD-10, and is characterized by severe, highly persistent depression, and a loss of interest or pleasure in everyday...
, or hypoglycemia
Hypoglycemia
Hypoglycemia or hypoglycæmia is the medical term for a state produced by a lower than normal level of blood glucose. The term literally means "under-sweet blood"...
(low blood sugar) may mimic psychosis
Psychosis
Psychosis means abnormal condition of the mind, and is a generic psychiatric term for a mental state often described as involving a "loss of contact with reality"...
.
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
Transcranial magnetic stimulation
Transcranial magnetic stimulation is a noninvasive method to cause depolarization or hyperpolarization in the neurons of the brain...
and electroconvulsive therapy
Electroconvulsive therapy
Electroconvulsive therapy , formerly known as electroshock, is a psychiatric treatment in which seizures are electrically induced in anesthetized patients for therapeutic effect. Its mode of action is unknown...
. Types of non-biological treatments such as cognitive therapy
Cognitive therapy
Cognitive behavioral therapy is a psychotherapeutic approach: a talking therapy. CBT aims to solve problems concerning dysfunctional emotions, behaviors and cognitions through a goal-oriented, systematic procedure in the present...
, behavioral therapy, and psychodynamic psychotherapy
Psychodynamic psychotherapy
Psychodynamic psychotherapy is a form of depth psychology, the primary focus of which is to reveal the unconscious content of a client's psyche in an effort to alleviate psychic tension. In this way, it is similar to psychoanalysis. It also relies on the interpersonal relationship between client...
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
Schizophrenia
Schizophrenia is a mental disorder characterized by a disintegration of thought processes and of emotional responsiveness. It most commonly manifests itself as auditory hallucinations, paranoid or bizarre delusions, or disorganized speech and thinking, and it is accompanied by significant social...
.
Diagnostic process
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. Another problem with misdiagnosis is that a treatment for one condition might exacerbate other conditions. In other cases apparent mental health disorders could be a side effect of a serious biological problem such as concussion, brain tumor, or hormonal abnormality, which could require medical or surgical intervention.Disorders and biologic treatment
- Seasonal affective disorderSeasonal affective disorderSeasonal affective disorder , also known as winter depression, winter blues, summer depression, summer blues, or seasonal depression, is a mood disorder in which people who have normal mental health throughout most of the year experience depressive symptoms in the winter or summer, spring or autumn...
: Light boxLight therapyLight therapy or phototherapy consists of exposure to daylight or to specific wavelengths of light using lasers, light-emitting diodes, fluorescent lamps, dichroic lamps or very bright, full-spectrum light, usually controlled with various devices...
, SSRIs - Clinical depressionDepression (mood)Depression is a state of low mood and aversion to activity that can affect a person's thoughts, behaviour, feelings and physical well-being. Depressed people may feel sad, anxious, empty, hopeless, helpless, worthless, guilty, irritable, or restless...
: SSRIs (Prozac), SNRIs Effexor, atypical antidepressants: (Wellbutrin, Remeron), tricyclic antidepressants, monoamine oxidase inhibitors, electroconvulsive therapyElectroconvulsive therapyElectroconvulsive therapy , formerly known as electroshock, is a psychiatric treatment in which seizures are electrically induced in anesthetized patients for therapeutic effect. Its mode of action is unknown...
, transcranial magnetic stimulationTranscranial magnetic stimulationTranscranial magnetic stimulation is a noninvasive method to cause depolarization or hyperpolarization in the neurons of the brain... - Bipolar disorderBipolar disorderBipolar disorder or bipolar affective disorder, historically known as manic–depressive disorder, is a psychiatric diagnosis that describes a category of mood disorders defined by the presence of one or more episodes of abnormally elevated energy levels, cognition, and mood with or without one or...
: lithium carbonateLithium carbonateLithium carbonate is a chemical compound of lithium, carbon, and oxygen with the formula Li2CO3. This colorless salt is widely used in the processing of metal oxides and has received attention for its use in psychiatry. It is found in nature as the rare mineral zabuyelite.-Properties:Like almost...
, valproic acidValproic acidValproic acid is a chemical compound that has found clinical use as an anticonvulsant and mood-stabilizing drug, primarily in the treatment of epilepsy, bipolar disorder, and, less commonly, major depression. It is also used to treat migraine headaches and schizophrenia...
, Lamictal, carbamazepineCarbamazepineCarbamazepine is an anticonvulsant and mood-stabilizing drug used primarily in the treatment of epilepsy and bipolar disorder, as well as trigeminal neuralgia... - SchizophreniaSchizophreniaSchizophrenia is a mental disorder characterized by a disintegration of thought processes and of emotional responsiveness. It most commonly manifests itself as auditory hallucinations, paranoid or bizarre delusions, or disorganized speech and thinking, and it is accompanied by significant social...
: Includes haloperidolHaloperidolHaloperidol is a typical antipsychotic. It is in the butyrophenone class of antipsychotic medications and has pharmacological effects similar to the phenothiazines....
, clozapineClozapineClozapine is an antipsychotic medication used in the treatment of schizophrenia, and is also used off-label in the treatment of bipolar disorder. Wyatt. R and Chew...
, olanzapineOlanzapineOlanzapine is an atypical antipsychotic, approved by the FDA for the treatment of schizophrenia and bipolar disorder...
, risperidoneRisperidoneRisperidone is a second generation or atypical antipsychotic, sold under the trade name . It is used to treat schizophrenia , schizoaffective disorder, the mixed and manic states associated with bipolar disorder, and irritability in people with autism...
, QuetiapineQuetiapineQuetiapine , is an atypical antipsychotic approved for the treatment of schizophrenia, and bipolar disorder....
, ZiprasidoneZiprasidoneZiprasidone was the fifth atypical antipsychotic to gain FDA approval . In the United States, Ziprasidone is Food and Drug Administration approved for the treatment of schizophrenia, and the intramuscular injection form of ziprasidone is approved for acute agitation in schizophrenic patients...
and other antipsychoticAntipsychoticAn antipsychotic is a tranquilizing psychiatric medication primarily used to manage psychosis , particularly in schizophrenia and bipolar disorder. A first generation of antipsychotics, known as typical antipsychotics, was discovered in the 1950s...
s - Generalized anxiety disorder: SSRIs, benzodiazepineBenzodiazepineA benzodiazepine is a psychoactive drug whose core chemical structure is the fusion of a benzene ring and a diazepine ring...
s, buspironeBuspironeBuspirone is an anxiolytic psychoactive drug of the azapirone chemical class, and is primarily used to treat generalized anxiety disorder Bristol-Myers Squibb gained FDA approval of buspirone in 1986 for treatment of GAD... - Obsessive-compulsive disorderObsessive-compulsive disorderObsessive–compulsive disorder is an anxiety disorder characterized by intrusive thoughts that produce uneasiness, apprehension, fear, or worry, by repetitive behaviors aimed at reducing the associated anxiety, or by a combination of such obsessions and compulsions...
: clomipramineClomipramineClomipramine is a tricyclic antidepressant . It was developed in the 1960s by the Swiss drug manufacturer Geigy and has been in clinical use worldwide ever since.- Indications :...
, SSRIs citalopramCitalopramCitalopram brand names: Celexa, Cipramil) is an antidepressant drug of the selective serotonin reuptake inhibitor class. It has U.S...
Early 20th century
Sigmund FreudSigmund Freud
Sigmund Freud , born Sigismund Schlomo Freud , was an Austrian neurologist who founded the discipline of psychoanalysis...
was originally focused on the biological causes of mental illness. Freud's professor and mentor, Ernst Wilhelm von Brücke
Ernst Wilhelm von Brücke
Ernst Wilhelm Ritter von Brücke was a German physician and physiologist.He was born Ernst Wilhelm Brücke in Berlin. He graduated in medicine at University of Berlin in 1842, the following year he became esearch assistant to Johannes Peter Müller...
, strongly believed that thought and behavior were determined by purely biological factors. Freud initially accepted this and was convinced that certain drugs (particularly cocaine
Cocaine
Cocaine is a crystalline tropane alkaloid that is obtained from the leaves of the coca plant. The name comes from "coca" in addition to the alkaloid suffix -ine, forming cocaine. It is a stimulant of the central nervous system, an appetite suppressant, and a topical anesthetic...
) 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
Psychoanalysis
Psychoanalysis is a psychological theory developed in the late 19th and early 20th centuries by Austrian neurologist Sigmund Freud. Psychoanalysis has expanded, been criticized and developed in different directions, mostly by some of Freud's former students, such as Alfred Adler and Carl Gustav...
theories.
Nearly 100 years ago, Harvey Cushing
Harvey Cushing
Harvey Williams Cushing, M.D. , was an American neurosurgeon and a pioneer of brain surgery, and the first to describe Cushing's syndrome...
, the father of neurosurgery
Neurosurgery
Neurosurgery is the medical specialty concerned with the prevention, diagnosis, treatment, and rehabilitation of disorders which affect any portion of the nervous system including the brain, spine, spinal cord, peripheral nerves, and extra-cranial cerebrovascular system.-In the United States:In...
, noted that pituitary gland
Pituitary gland
In vertebrate anatomy the pituitary gland, or hypophysis, is an endocrine gland about the size of a pea and weighing 0.5 g , in humans. It is a protrusion off the bottom of the hypothalamus at the base of the brain, and rests in a small, bony cavity covered by a dural fold...
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.
Mid 20th century
An important point in modern history of biological psychiatry was the discovery of modern antipsychoticAntipsychotic
An antipsychotic is a tranquilizing psychiatric medication primarily used to manage psychosis , particularly in schizophrenia and bipolar disorder. A first generation of antipsychotics, known as typical antipsychotics, was discovered in the 1950s...
and antidepressant
Antidepressant
An antidepressant is a psychiatric medication used to alleviate mood disorders, such as major depression and dysthymia and anxiety disorders such as social anxiety disorder. According to Gelder, Mayou &*Geddes people with a depressive illness will experience a therapeutic effect to their mood;...
drugs. Chlorpromazine
Chlorpromazine
Chlorpromazine is a typical antipsychotic...
(also known as Thorazine), an antipsychotic, was first synthesized in 1950, and iproniazid
Iproniazid
Iproniazid is a hydrazine drug used as an antidepressant. It acts as an irreversible and nonselective monoamine oxidase inhibitor . Though it has been widely discontinued in most of the world, it is still used in France.- History :Iproniazid was the first antidepressant ever marketed...
, one of the first antidepressants, was first synthesized in 1957. In 1959 imipramine
Imipramine
Imipramine , also known as melipramine, is an antidepressant medication, a tricyclic antidepressant of the dibenzazepine group...
, the first tricyclic antidepressant
Tricyclic antidepressant
Tricyclic antidepressants are heterocyclic chemical compounds used primarily as antidepressants. The TCAs were first discovered in the early 1950s and were subsequently introduced later in the decade; they are named after their chemical structure, which contains three rings of atoms...
, was developed. Research into the action of these drugs led to the first modern biological theory of mental health disorders called the catecholamine
Catecholamine
Catecholamines are molecules that have a catechol nucleus consisting of benzene with two hydroxyl side groups and a side-chain amine. They include dopamine, as well as the "fight-or-flight" hormones adrenaline and noradrenaline released by the adrenal medulla of the adrenal glands in response to...
theory, later broadened to the monoamine theory, which included serotonin. These were popularly called the "chemical imbalance" theory of mental health disorders.
Late 20th century
Starting with fluoxetineFluoxetine
Fluoxetine is an antidepressant of the selective serotonin reuptake inhibitor class. It is manufactured and marketed by Eli Lilly and Company...
(marketed as Prozac) in 1988, a series of monoamine-based antidepressant
Antidepressant
An antidepressant is a psychiatric medication used to alleviate mood disorders, such as major depression and dysthymia and anxiety disorders such as social anxiety disorder. According to Gelder, Mayou &*Geddes people with a depressive illness will experience a therapeutic effect to their mood;...
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. Most operate on the same principle, which is modulation of monoamines (neurotransmitters) in the neuronal synapse
Synapse
In the nervous system, a synapse is a structure that permits a neuron to pass an electrical or chemical signal to another cell...
. 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 somewhat less effective than previously thought.
Problems with catecholamine/monoamine hypotheses
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 reserpineReserpine
Reserpine is an indole alkaloid antipsychotic and antihypertensive drug that has been used for the control of high blood pressure and for the relief of psychotic symptoms, although because of the development of better drugs for these purposes and because of its numerous side-effects, it is rarely...
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.
Latest biological hypotheses of mental health disorders
New research indicates different biological mechanisms may underlie some mental health disorders, only indirectly related to neurotransmitters and the monoamine "chemical imbalance theory."Recent research indicates a biological "final common pathway" may exist which both electroconvulsive therapy
Electroconvulsive therapy
Electroconvulsive therapy , formerly known as electroshock, is a psychiatric treatment in which seizures are electrically induced in anesthetized patients for therapeutic effect. Its mode of action is unknown...
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.
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.
This is called the neurogenic hypothesis of depression. It promises to explain pharmacological antidepressant action, 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, 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. 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.
Criticism
A vocal minority 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 biomarkersBiomarker (medicine)
In medicine, a biomarker is a term often used to refer to a protein measured in blood whose concentration reflects the severity or presence of some disease state...
for recognized psychiatric conditions. This position has been represented in niche academic journals such as The Journal of Mind and Behavior and Ethical Human Psychology and Psychiatry, which publishes material specifically countering "the idea that emotional distress is due to an underlying organic disease." 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.
Fields such as social psychiatry
Social psychiatry
Social psychiatry is a branch of psychiatry that focuses on the "interpersonal" and cultural context of mental disorder and mental wellbeing. It involves a sometimes disparate set of theories and approaches, with work stretching from epidemiological survey research on the one hand, to an indistinct...
, clinical psychology
Clinical psychology
Clinical psychology is an integration of science, theory and clinical knowledge for the purpose of understanding, preventing, and relieving psychologically-based distress or dysfunction and to promote subjective well-being and personal development...
, and sociology
Sociology
Sociology is the study of society. It is a social science—a term with which it is sometimes synonymous—which uses various methods of empirical investigation and critical analysis to develop a body of knowledge about human social activity...
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
Scientific method
Scientific method refers to a body of techniques for investigating phenomena, acquiring new knowledge, or correcting and integrating previous knowledge. To be termed scientific, a method of inquiry must be based on gathering empirical and measurable evidence subject to specific principles of...
because they believe there is no testable
Falsifiability
Falsifiability or refutability of an assertion, hypothesis or theory is the logical possibility that it can be contradicted by an observation or the outcome of a physical experiment...
biological evidence of mental disorders. Thus, these critics view biological psychiatry as a pseudoscience
Pseudoscience
Pseudoscience is a claim, belief, or practice which is presented as scientific, but which does not adhere to a valid scientific method, lacks supporting evidence or plausibility, cannot be reliably tested, or otherwise lacks scientific status...
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
Confirmation bias
Confirmation bias is a tendency for people to favor information that confirms their preconceptions or hypotheses regardless of whether the information is true.David Perkins, a geneticist, coined the term "myside bias" referring to a preference for "my" side of an issue...
.
External links
- NYTimes.com - 'Study Finds a Link of Drug Makers to Psychiatrists', Benedict Carey, New York Times (April 20, 2006)
- PsychologyToday.com - 'Depression: Beyond Serotonin: Much more than a chemical imbalance, depression is a disorder of mind, brain, and body', Hara Estroff Marano, Psychology TodayPsychology TodayPsychology Today is a bi-monthly magazine published in the United States. It is a psychology-based magazine about relationships, health, and related topics written for a mass audience of non-psychologists. Psychology Today was founded in 1967 and features articles on such topics as love,...
(March, 1999)