15.2.2 Schizophrenia 3 Flashcards
The eventual results are mild abnormalities in brain ____ and major disorders of ____.
anatomy : behaviour
The risk of schizophrenia is elevated among people who had problems that could have affected their ____ ____, including poor nutrition of mother during pregnancy, premature birth, low birth weight, and complications during delivery.
brain development
The risk is also elevated if the mother was exposed to ____ ____, such as the sudden death of a close relative, early in her pregnancy.
extreme stress
Schizophrenia has also been linked to ____ ____ in early childhood.
head injuries
Another suggestion of prenatal influences comes from the __________ ____: the tendency for people born in winter to have a slightly greater probability of developing schizophrenia than people born at other times of the year.
season-of-birth effect
Another influence is ____ ____. Influenza and other viral epidemics are most common in the autumn. Therefore, many pregnant woman become infected in the autumn with a virus that impairs a crucial stage of brain development in a baby who will be born in the winter.
viral infection
Rates of schizophrenia are also increased among offspring of mothers who had ____ (German measles), ____, and other infections during pregnancy.
rubella, herpes
Certain childhood ____ may also relate to schizophrenia.
infections
In accord with the neurodevelopmental hypothesis, some people with schizophrenia show mild abnormalities of ____ ____ that vary from one individual to another.
brain anatomy
The areas with consistent signs of abnormality include some that mature slowly, such as the ____ ____ ____.
dorsolateral prefrontal cortex
The abnormalities include weaker than average connections from the dorsolateral prefrontal cortex to other brain areas, and less than normal activity in this area during tasks requiring ____ and ____.
attention and memory
As you might predict, people with schizophrenia perform poorly at tasks that depend on the ____ ____.
prefrontal cortex
At a microscopic level, the most reliable finding is that ____ ____ of those with schizophrenia are smaller than normal, especially in the hippocampus and prefrontal cortex.
cell bodies
Before antipsychotic drugs became available in the mid-1950s, most people with schizophrenia were confined to ____ ____ with little hope of recovery.
mental hospitals
In the 1950s, psychiatrists discovered that ____ (trade name Thorazine) relieves the positive symptoms of schizophrenia for most, though not all, patients.
chlorpromazine
Researchers later discovered other ____, or ____, drugs (drugs that tend to relieve schizophrenia and similar conditions) in two chemical families.
antipsychotic or neuroleptic
The chemical families are: the ____, which include chlorpromazine, and the ____, which include haloperidol (trade name Haldol).
phenothiazines : butyrophenones
Symptoms of schizophrenia generally ____ after cessation of treatment with theses drugs.
return
Each of these drugs blocks ____ synapses.
dopamine
Drugs that are the most effective against schizophrenia (and therefore used in the smallest doses) are the most effective at blocking ____ ____.
dopamine receptors
That finding inspired the ____ ____ of schizophrenia, which holds that schizophrenia results from excess activity at dopamine synapses in certain brain areas.
dopamine hypothesis
Although the concentration of dopamine in the brain is no higher than normal, the turnover is elevated, especially in the ____ ____.
basal ganglia
Neurons release dopamine at a faster than average rate and ____ more to replace the molecules that they do not reabsorb.
synthesise
Further support for the dopamine hypothesis comes from the fact that large, repeated use of amphetamine, methamphetamine, or cocaine induces ____ ____ ____, categorised by hallucinations and delusions, the positive symptoms of schizophrenia.
substance-induced psychotic disorder
Each of these drugs increases or ____ the activity at dopamine synapses.
prolongs
According to the ____ ____ of schizophrenia, the problem relates in part to deficient activity at glutamate synapses especially in the prefrontal cortex.
glutamate hypothesis
In many brain areas, ____ ____ ____ release, or glutamate stimulates neurons that inhibit dopamine release. Therefore, increased dopamine would produce the same effects is decreased glutamate.
dopamine inhibits glutamate
The drugs that block dopamine synapses produce their benefits by acting on neurons in the ____ ____, a set of neurons that project from the midbrain tegmenum to the limbic system.
mesolimbocortical system
However, the drugs also block dopamine neurons in the ____ ____ that projects to the basal ganglia.
mesostriatal system
The effect of dopamine blocking drugs on the basal ganglia produces ____ ____, characterised by tremors and other involuntary movements that develop gradually and to varying degrees among different patients.
tardive dyskinesia
Once tardive dyskinesia emerges, it can ________ someone quits the drug. Consequently, the best strategy is to prevent it from starting.
last long after
Certain new drugs called ____ ____, or atypical antipsychotics, alleviate schizophrenia without producing movement problems.
second-generation antipsychotics
The most common of these second-generation ____ are clozapine, amisulpride, risperidone, olanzapine, and aripiprazole.
antipsychotics
Unfortunately, although these new drugs avoid tardive dyskinesia, they produce other side effects, including ____ ____ and impairment of the ____ ____.
weight gain : immune system
