Current paradigms in psychopathology
Science is a human enterprise that is bound by scientists’ human limitations.
Paradigm: a conceptual framework or approach within a scientist works.
A paradigm as profound implications for how scientist operate at any given time.
- Paradigms specify what problems scientists will investigate and how they will go about the investigation.
Three paradigms that guide the study and treatment of psychopathology
- Cognitive behavioral
Factors that cut across all the paradigms:
- Sociocultural factors
Almost all behavior is heritable to some degree.
Despite this, genes do not operate in isolation from the environment. Through the life span, the environment shapes how our genes are expressed, and our genes also shape the environment.
Nature via nurture.
Without the environment, genes could not express themselves and thus contribute to behavior.
Genes: the carriers of genetic information.
The number of genes is not important. The sequencing, or ordering, of these genes as well as their expression is what makes us unique.
What genes do matters more than the number of genes we have. Genes make proteins that in turn make the body and the brain work.
Gene expression: some proteins switch, or turn, on and off other genes.
Polygenic: several genes turning themselves on and off as they interact with a person’s environment is the essence of genetic vulnerability.
We do not inherit mental illness from our genes. We develop mental illness trough the interaction of our genes with our environment.
Heritability: the extent to which variability in a particular behavior in a population can be accounted for by genetic factors.
- Rages from 0.0 to 1.0. The higher the number, the greater the heritability.
- Heritability is relevant only for a large population of people, not a particular individual.
Shared environment factors: those things that members of a family have in common, such as parents’ marital status.
Nonshared environment (or unique environment) factors: those things believed to be important in understanding why two siblings from the same family can be so different.
Nonshared environmental experiences have much more to do with the development of mental illness than the shared experiences.
Behavior genetics: the study of the degree to which genes and environmental factors influence behavior.
Genotype: the total genetic makeup of an individual, consisting of inherited genes. The genotype cannot be observed outwardly.
Phenotype: the totality of observable behavioral characteristics.
The genotype should not be viewed as a static entity. Genetic programs are quite flexible.
The phenotype changes over time and is the product of an interaction between the genotype and the environment.
Molecular genetics studies seek to identify particular genes and their functions.
Alleles: different forms of the same gene. The alleles of a gene are found at the same location, or locus, of a chromosome pair.
Polymorphism: a difference in DNA sequence on a gene that has occurred in a population.
The DNA in genes is transcribed to RNA. In some cases, the RNA is then translated into amino acids, which then form proteins, and proteins make cells.
Gene expression involves types of DNA called promoters. These promoters are recognized by particular proteins called transcription factors.
Single nucleotide polymorphisms (SNPs): differences between people in a single nucleotide in the DNA sequence of a particular gene.
Copy number variations (CNVs): an abnormal copy of one or more sections of DNAa within the gene(s).
Can be present in single gene or multiple genes.
- Additions, extra copies are abnormally present
- Deletions, copies are missing
Gene-environment interaction: a given person’s sensitivity to an environmental event is influenced by genes.
Epigenetics: the study of how the environment can alter gene expression of function.
Reciprocal gene-environment interactions
Reciprocal gene-environment interactions: how genes may promote certain types of environment.
Genes may predispose us to seek out certain environments that then increase our risk for developing a particular disorder.
The neuroscience paradigm: mental disorders are linked to aberrant processes in the brain.
Neurons and neurotransmitters
Each neuron has four major parts:
- The cell body
- Several dendrites, the short and thick extensions
- One or more axons of varying lengths, but usually one long and thin axon that extends a considerable distance from the cell body
- Terminal buttons on the many end branches of the axon
When a neuron is approximately stimulated at its cell body or through its dendrites, a nerve impulse travels down the axon to terminal endings.
Between the terminal endings of the sending axon and the cell membrane of the receiving neuron, there is a mall gap. The synapse.
Neurotransmitters: chemicals that allow neurons to send a signal across the synapse to another neuron.
- As the neurotransmitter flows into the synapse, some of the molecules reach the receiving, postsynaptic, neuron. Receptors are configured so that only specific neurotransmitters can fit into them.
When a neurotransmitter fits into a receptor site, a message can be sent to the postsynaptic cell.
What happens to the postsynaptic neuron depends on integrating thousands of similar messages.
Leading to the creation of a nerve impulse in the postsynaptic cell
Making the postsynaptic cell less likely to create a nerve impulse
- Once a presynaptic neuron (sending) has released its neurotransmitter, the last step is for the synapse to return to its normal state. Not all of the released neurotransmitter has found its way to postsynaptic receptors. Some of what remains in the synapse is broken down by enzymes, and some is taken back into the presynaptic cell. → reuptake
- Gamma-aminobutyric acid (GABA)
Serotonin and dopamine may be involved in depression, mania, and schizophrenia.
Norepinephrine communicates with the sympathetic nervous system, where it is involved in producing states of high arousal.
GABA inhibits nerve impulses throughout most areas of the brain and may be involved in the anxiety disorders.
Neurotransmitters are synthesized in the neuron through a series of metabolic steps, beginning with an amino acid. Each reaction along the way to producing an actual neurotransmitter is catalyzed by an enzyme.
Too much or too little of a particular neurotransmitter could result form an error in these metabolic steps.
Similar disturbances in the amounts of specific transmitters could results from alterations in the usual processes by which transmitters are deactivated after being released into the synapse.
There is also a possibility that the neurotransmitter receptors are at fault in some disorders. If they are to numerous or too easily exited.
Many mechanisms control the sensitivity of postsynaptic neurons.
- If a receptor has been activated extensively over time, the cell may retune the sensitivity of the receptor so that it becomes more difficult to create a nerve impulse.
- When a cell has been firing more frequently, this receptor releases second messengers. Helping a neuron adjust receptor sensitivity when it has been overly active.
Agonist: drug that stimulates a particular neurotransmitter’s receptors.
Antagonist: a drug that works on a neurotransmitter’s receptors to dampen the activity of that neurotransmitter.
Glial cell: not only interact with neurons, but also help to control how neurons work.
Structure and function of the human brain
The brain is located within the protective coating of the skull and is enveloped with three protective layers of membranes referred to as meninges.
- Viewed from the top, the brain is divided by a midline fissure into two mirror-image cerebral hemispheres, together they constitute most of the cerebrum.
- The connection between the two hemispheres is the corpus callosum.
- Gray matter. The thin outer layers of tightly packed neurons.
The cortex is vastly convoluted: gyri (ridges) and sulci (depressions of fissures)
The sculi are used to define different regions of the brain.
Deep fissures divide the cerebral hemispheres into four distinct areas called lobes.
- Frontal lobe. In the from of the central sulcus. Reasoning, problem solving, working memory, and emotion regulation.
- Parietal lobe. Being it and above the lateral sulcus
- Temportal lobe. Below the lateral sulcus. Discriminations of sound
- Occipital lobe. Beind the parietal and temporal lobes. Vision
Prefrontal cortex. In the very front of the cortex. Helps regulate the amygdala.
The gray matter of the cerebral cortex does not extend throughout the interior of the brain. Much of the interior is white matter.
White matter is made up of large tracts of myelinated fibers that connect cell bodies in the cortex with those in the spinal cord and in other centers lower in the brain.
Nuclei: certain areas where sets of nerves converge and messages are integrated from different centers.
- Basal ganglia:
Help regulate stating and stopping both motor and cognitive activity.
Willed with cerebrospinal fluid. Cerebrospinal fluid circulates through the brain through these ventricles, which are connected with the spinal cord.
Arelay station for all sensory pathways except the olfactory.
- Brain stem:
Comprised of the pons and the medulla oblongata. Functions primarily as a neural relay station.
- The pons contains tracts that connect the cerebellum with the spinal cord and with motor areas of the cerebrum.
- The medulla oblongata serves as the main line of traffic for tracts ascending from the spinal cord and descending form the higher centers of the brain.
Receives sensory nerves from the vestibular apparatus of the ear and from muscles, tendons, and joints. The information received and integrated relates to balance, posture, equilibrium, and the smooth coordination of the body when in motion.
- Limbic system.
Support the visceral and physical expressions of emotion. And the expression of appetite and other primary drives.
- Anterior cingulate:
An area just above the corpus callosum
- Septal area:
Anterior to the thalamus
Stretches from the septal area into the temporal lobe
Regulates metabolism, temperature, persipiration, blood pressure, sleeping and appetite.
Embedded in the tip of the temporal lobe. An important area for attention to emotionally salient stimuli and memory of emotionally relevant events.
The neuroendocrine system
HPA axis is central to the body’s response to stress.
When people are faced with treat, the hypothalamus releases corticotropine-releasing factor (CRF), which ten communicates with the pituitary gland.
The pituitary gland then releases adrenocorticotropic hormone, which travels via the blood to the adrenal glands.
The outer layers of the adrenal glands are referred to as the adrenal cortex. This area promotes the release of the hormone cortisol.
Cortisol: the stress hormone.
Evaluating the neuroscience paradigm
Caution: the whole is greater than the sum of parts.
Influences from behavior therapy
One of the key influences from behaviorism is the notion that problem behavior is likely to continue if its is reinforced.
Generally, problem behavior is thought to be reinforced by four possible consequences:
- Getting attention
- Escaping from tasks
- Generating sensory feedback
- Gaining access to desirable things or situations
Once the sources of reinforcement has been identified, treatment is then tailored to alter the consequences of the problem behavior.
Operant techniques have been particularly successful in the treatment of many childhood problems.
Once contingencies shape a behavior, a key goal is to maintain the effect of treatment.
- Intermittent reinforcement
- Behavioral activation (BA) therapy.
Involves helping a person engage in tasks that provide an opportunity for positive reinforcement.
In vivo: in real-life situations.
Exposure continues to be a centrally important component of many forms of cognitive behavior therapy.
- In vivo is more effective than imaging situations.
- Relaxation is not necessary
Cognition: groups together the mental processes of perceiving, recognizing, conceiving, judging, and reasoning.
Cognitive scientists regard people as active interpreters of a situations.
A person fits new information into a schema.
New information may fit the schema, if not, the person reorganizes the schema to fit the information or construes the information in such a way as to fit the schema.
Important contributions from cognitive science
The role of the unconscious
Implicit memory: the idea that a person can, without being aware of it, be influenced by prior learning.
Brains have developed the capacity to register information for later use if we are not aware of it.
Cognitive behavior therapy
Cognitive behavior therapy (CBT) incorporates theory and research on cognitive processes.
Cognitive behavior therapists pay attention to private events and have studied and manipulated these processes in their attempts to understand and modify overt and covert distributed behavior.
Cognitive restructuring: a general term for changing a pattern of thought.
Beck’s cognitive therapy
Psychiatrists Aaron Back developed a cognitive therapy for depression based on the idea that depressed mood is caused by distortions in the way people perceive life experiences.
Beck proposed that the attention, interpretation, and recall of negative and positive information are biased in depression. These effects on attention and memory are called information-processing biases.
Beck’s therapy is now adapted for other disorders in addition to depression.
It addresses biases by trying to persuade patients to change their opinions of themselves and the way in which they interpret life events.
Evaluating the cognitive behavioral paradigm
Childhood is unconsidered.
And unanswered where the schema came from in the first place.
Three important factors
- Socio-cultural factors
- Interpersonal factors
Emotion and psychopathology
Emotions influence how we respond to problems and challenges in our environment. They help us organize our thoughts and actions, both explicitly and implicitly, and they guide our behavior.
Disturbances in emotion figure prominently in many different forms of psychopathology.
Emotions are believed to be fairly short-lived states, lasting for a few seconds, minutes, or at most hours.
Affect: long-lasting emotional feelings.
Moods: emotional experiences that endure for a longer period of time.
Emotions are comprised of a number of components including (not limited to)
Typically facial expression
How someone reports he or she feels at any given moment or in response to some event
Changes in the body
These components are typically coordinated within the individual.
When we consider emotional disturbances in psychopathology, it will be important to consider which of the emotion components are affected.
Another important consideration is the concept of ideal affect, which is the kinds of emotional states that a person ideally wants to feel. Varies depending on cultural factors.
Sociocultural factors and psychopathology
Environmental factors can trigger, exacerbate, or maintain the symptoms that make up the different disorders.
The range variables considered and the ways of studying those variables cover a lot of ground.
- Cultural and ethnic factors
Even though there are some cross-cultural similarities in the presence of mental illness across cultures, there are also a number of profound cultural influences on the symptoms expressed in different disorders, the availability of treatment, and the willingness to seek treatment.
Interpersonal factors and psychopathology
How the quality of relationships influences different disorders.
Object relations theory: stresses the importance of long-standing patterns in close relationship,, particularly within the family, that are shaped by the ways in which people think and feel. The ‘object’ refers to another person in most versions of this theory.
Relational self: the self in relations to others.
Interpersonal therapy (IPT): emphasizes the importance of current relationships in a person’s life and how problems in these relationships can contribute to psychological symptoms.
The therapist fist encourages the patient to identify feelings about his or her relationships and to express these feelings, and then helps the patient generate solutions to interpersonal problems.
In IPT, four interpersonal issues are assessed to examine whether one or more might be impacting symptoms:
- Unresolved grief
- Role transitions
- Role disputes
- Interpersonal or social deficits
the therapist helps the patient understand that psychopathology occurs in a social or relationship context and that getting a better handle on relationship patterns is necessary to reduce symptoms of psychopathology.
Psychopathology is much too diverse to be explained or treated adequately by any one of the current paradigms.
Diathesis-stress paradigm: an integrative paradigm that links genetic, neurobiological, psychological, and environmental factors.
Diatheses: a predisposition toward a disease. May be extended to any characteristic or set of characteristics of a person that increases his or her chance of developing a disorder.
Possessing the diathesis for a disorder increases a person’s risk of developing it, but does not by any means guarantee that a disorder will develop.
Stress is meant to account for how a diathesis may be translated into an actual disorder.
Stress generally refers to some noxious or unpleasant environmental stimulus that triggers psychopathology.
Both diathesis and stress are necessary in the development of disorders.
Psychopathology is unlikely to result form the impact of any single factor.
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