neuroanatomical changes in PTSD
reductions bilaterally, both in the volume of the hippocampus and amygdala of the temporal lobes and of the frontal cortex; Reduced cortical thickness; reduced cerebral blood flow
posttraumatic stress disorder (PTSD)
Syndrome characterized by physiological arousal symptoms brought on by recurring memories and dreams related to a traumatic event for months or years after the event.
virtual-reality (VR) exposure therapy
Controlled, virtual-immersion environment that, by allowing individuals to relive traumatic events, gradually desensitizes them to stress.
Primitive functions, including the “instinctual drives” of sex and aggression, are lo- cated in the id, the part of the mind that Freud thought operated on an unconscious level.
The rational part of the mind he called the ego. Much of the ego’s activity Freud also believed to be unconscious, although experience (to him, our perceptions of the world) is conscious.
The super ego aspect of mind acts to repress the id and to mediate ongoing interactions between the ego and the id.
at work prenatally, later in life, even in succeeding generations
Progressive cell death
resulting from neurodegenerative causes, as in Parkinson’s or Al- zheimer’s disease
Rapid cell death
as in stroke or traumatic brain injury
Loss of neural function and connections
seen in disorders such as multiple sclerosis and myasthenia gravis
Causes of abnormal behavior
1. genetic errors 2. epigenetic mechanisms 3. progressive cell death 4. loss of neural function and connections
Movement within neuroscience and psychoanalysis to combine the insights of both to yield a unified understanding of mind and brain.
Behavioral disorder caused by elevated levels of the amino acid phenylalanine in the blood and resulting from a defect in the gene for the enzyme phenylalanine hydroxylase; the major symptom is severe mental retardation.
what do babies with PKU have in their blood?
elevated levels of phenylalanine in their blood.
how can PKU be treated?
by restricting the dietary intake of phenylalanine—foods high in protein, including beef, fish, cheese, and soy
what makes it difficult to know more about behavioral disorders?
their subjective nature
major obstacles to investigating behavioral disorders
1. organizational complexity 2. systemic complexity 3. neuronal plasticity 4. compensatory plasticity 5. technological resolution 6. modeling simplicity 7. modeling limitations
The brain has a wider variety of cell types than does any other organ, and the cells and their connections are plastic
multiple receptor systems serve many different functions; no clear demonstration of a single receptor system with a specific relation to a specific behavior has as yet been made
brain’s compensatory plasticity is considerable. When diseases progress slowly, the brain has a remarkable ca- pacity for adapting.
Just as brain lesions do not always produce behavioral symptoms, behavioral symptoms are not always linked to obvious neuropathology. Clearly, people display compensatory plasticity: they can change their behavior to adapt to neural change, and they can display abnormal behavior without obvious brain pathology.
The resolution of technology may always lack the detail to detect subtle neuronal change
One problem with animal models is that the view they provide of the neurobiology behind behavioral abnormali- ties is oversimplified. The fact that a drug reduces symptoms does not necessarily mean that it is acting on a key biochemical aspect of the pathology
Modeling human disorders is a complex task, so use caution when you encounter news stories about studies using animal models that point toward possible cures for human behavioral diseases.
how many people in the US suffers from a mental disorder in any given year?
1 in 4
what percentage of the US will have a mental disorder in their lifetime?
what is the leading cause of disability after age 15?
behavioral and neurological disorders
is the study of the distribution and causes of diseases in human populations.
three general types of psychiatric disorders
disorders of psychoses, mood, and affect.
what do imaging tests need to detect brain disorders?
imaging tests must be sensitive enough to detect unique features of brain disorders and specific enough to rule out similar conditions. This feature is problematic because many behavioral disorders display similar abnormalities
what disorders have enlarged ventricles?
indicate a loss of brain cells and may appear in schizophrenia, Alzheimer’s disease, alcoholism, or head trauma, for example.
what is found in people who develop schizophrenia between the ages of 13 and 18
remarkable loss of gray matter in the cerebral cortex
what do children with schizophrenia have?
a delayed growth rate in white matter—on the order of 2 percent per year; greatest in the right frontal lobe
The loss in cerebral gray and white matter in schizophrenia correlates with what?
the onset of a variety of behavioral disturbances characteristic of schizophrenia.
include disordered proteins in cell-membrane channels, low or high numbers of neuroreceptors, and low or high numbers of molecules, especially neurotransmitters or hormones.
Types of treatments
1. neurosurgical 2. electrophysiological 3. pharmacological 4. behavioral
The skull is opened and some intervention is performed on the brain
Brain function is modified by stimulation through the skull.
A chemical that affects the brain is either ingested or injected.
Treatment manipulates the body or the experience, which in turn influ- ences the brain
goal of neurosurgical manipulations?
goal of directly altering it have been largely reparative, as when tumors are removed or arteriovenous malforma- tions are corrected
what does neurosurgery do?
either damages some dysfunctional area of the brain or stimulates dysfunctional areas with electrodes
deep brain stimulation (DBS
Neurosurgery in which electrodes implanted in the brain stimulate a targeted area with a low-voltage electrical current to facilitate behavior.
where is the electrode placed with deep brain stimulation for treatment of Parkinson's?
the motor thalamus
what can DBS do in Parkinson's?
The stimulation can inactivate the tremor-producing area of the brain or activate the brain in other ways and so restore more normal movement.
what disorders has DBS been used to treat?
used experimentally to treat traumatic brain injury (TBI) and behavioral dysfunctions such as obsessive-compulsive disorder (OCD) and major depression.
return this region to the embryonic state and regrow a normal region.
what is one way to use induced neurogenesis?
stem cells can be induced by neurotrophic factors to generate new cells that can migrate to the site of an injury.
multipotent stem cells are located in what body regions?
bone marrow and skin, appear capable of manufacturing neural stem cells.
what was ECT developed for?
a treatment for otherwise untreatable depression, and al- though its mode of action was not understood, it did prove useful.
what is one mechanisms by which ECT may work?
it stimulates the production of a variety of neurotrophic factors, especially BDNF (brain-derived neurotrophic factor) that in turn restore inactive cells to a more active mode.
problems with ECT
the massive convulsions caused by the electrical stimulation. Large doses of medications are normally required to prevent them. ECT also leads to memory loss, a symptom that can be troublesome with repeated treatments.
transcranial magnetic stimulation (TMS), uses magnetic rather than electrical stimulation and is an FDA-approved treatment for depression.
benefits of TMS
a more focused treatment than ECT and will probably be far more widely used.
treatment for schizophrenia
provided the first drug treatment for serious motor dysfunction in Parkin- son’s disease
Inability to stop the tongue or other body parts from moving; motor side effect of neuroleptic drugs.
Treatment that applies learning principles, such as conditioning, to eliminate unwanted behaviors.
Psychotherapy based on the perspective that thoughts intervene between events and emotions, and thus the treatment of emotional disorders requires changing maladaptive patterns of thinking.
Talking therapy derived from Freudian psychoanalysis and other psychological interventions.
downsides of pharmacological treatments
Acute and chronic side effects top the list, and long-term effects may create new problems
does altering the brain JUST change our behavior?
No--altering our behavior ALSO changes the brain
what is behavior a product of?
all your learning and social experiences.
form of habituation (adaption to a repeatedly presented stimulus)
what do cognitive therapies do?
challenge a person’s self-defeating attitudes and assumptions
real-time fMRI (rt-fMRI)
Behavior- modification technique in which individuals learn to change their behavior by controlling their own patterns of brain activation.
what do music and exercise effect?
have positive effects on peoples’ attitudes, emotional well-being, and brain function
affects arousal and activates the motor and premotor cortex
what can music improve?
can improve gait in Parkinson’s and stroke patients.
what can physical activity improve?
improves well-being and counteracts the effects of depression.
goal of real-time fMRI
Using this behavior-modification technique, individuals learn to change their behavior by controlling their own pat- terns of brain activation.
real-time fMRI and pain
When subjects decrease brain activa- tion in regions associated with pain, they report decreased pain perception