Exam 5

Question 1

Which neurotransmitters are thought to contribute to dysfunction in ADHD?

Answer 1

Dopamine, serotonin

Question 2

Which type of brain tumor is easiest to identify with CT scan?

Answer 2

Meningiomas because they are encapsulated

Question 3

The brain damage resulting from ischemia is related to excess release of what neurotransmitter?

Answer 3

Glutamate

Question 4

Many patients with Parkinson’s disease are treated with L-dopa, but a controversial treatment currently used in some patients is

Answer 4

Deep brain stimulation- a treatment in which low-intensity electrical stimulation is continually applies to an area of the brain through stereotaxically implanted electrode

Question 5

At what age do individuals typically develop schizophrenia?

Answer 5

Adolescence and early adulthood

Question 6

What is the dopamine theory of schizophrenia and describe the two facts that supported the initial dopamine theory?

Answer 6

The theory that schizophrenia is cause by too much dopamine

1) anti-schizophrenia drugs (drugs that reduce symptoms) deplete the brain of dopamine by breaking down synaptic vesicles storing dopamine
2) drugs such as amphetamine and cocaine trigger schizophrenia in healthy users and increase extracellular dopamine levels

Question 7

Abnormalities in which neurotransmitters have been suggested to be involved in autism spectrum disorders?

Answer 7

Serotonin, endorphins

Question 8

The dopamine theory of schizophrenia was revised to assert that schizophrenia is caused by hyperactivity in D2 receptors specifically instead of all dopamine receptors. Describe evidence provided by Snyder and colleagues that supports the revised theory of schizophrenia

Answer 8

The degree to which neuroleptics (anti-schizophrenia drugs) bind to D2 receptors is highly correlated with effectiveness in suppressing schizophrenic symptoms

Question 9

Neuroimaging in schizophrenia has revealed?

Answer 9

1) reduced volume in many areas of the brain

2) enlarged ventricles

Question 10

Describe the findings of the studied of the effectiveness of antidepressant medication to treat depression

Answer 10

• 50% of patients provided with any type of antidepressant medication improve; 25% of patients provided with a placebo improve
• antidepressants were not better than placebos in treating those with mild or moderate depression

Question 11

List the three regions shown to be abnormal in neuroimaging studies of affective disorders

Answer 11

1) amygdala
2) medial prefrontal cortex
3) hippocampus

Question 12

Describe evidence supporting the monoamine theory of depression

Answer 12

Monoamine oxidase inhibitors, tricyclic antidepressants, selective serotonin-reuptake inhibitors, and selective norepinephrine-reuptake inhibitors are all agonists of serotonin, norepinephrine, or both

In clinically depressed persons, those with more numerous norepinephrine and serotonin receptors found at autopsy were those who had not taken antidepressants (when less neurotransmitters is released, more receptors for the neurotransmitters are produced)

Question 13

Describe the neuroplasticity of depression

Answer 13

Depression results from a decrease of neuroplastic processes in the prefrontal cortex, hippocampus, amygdala, and other brain structures which leads to neuron loss and other forms of neural pathology

Question 14

Describe electrical stimulation treatment for depression

Answer 14

Electrode stimulating white matter of anterior cingulate gyrus in medial prefrontal cortex reduced symptoms in 65% of patients treated

Question 15

Describe the categories of drugs used to treat anxiety disorders

Answer 15

1) Benzodiazepines (Librium, Valium)- GABA agonists: Bind to receptors and facilitate effects of GABA; highly addictive
2) Serotonin agonists (Buspirone, SSRI)- Reduce anxiety without sedation or serious side effects

Question 16

Neuroimaging studied of Tourette’s disorder have suggested that ability to suppress tics involved which brain regions

Answer 16

Medial prefrontal cortex- decides and plans to suppress tics

Caudate- suppresses tics

Question 17

Structural neuroimaging studies of children with Tourette’s provide info about brain regions responsible for tics

Answer 17

Thinning in sensorimotor cortex

Question 18

What neurotransmitter is effected by neuroleptic drugs? Which disorders are treated with neuroleptics?

Answer 18

D2 receptor blockers; used to treat schizophrenia and Tourette’s syndrome

Question 19

Nigrostriatal pathway

Answer 19

Substantial nigra —-> dorsal striatum

Question 20

Mesocorticolimbic pathway

Answer 20

Ventral tegmental area —> nucleus accumbens

Question 21

Describe findings of animal studies supoorting the role of mesocorticolimbic pathway and particularly, the nucleus accumbens, to rewarding effects of drugs

Answer 21

• laboratory animals self-administered drugs into the nucleus accumbens
• injections of addictive drugs into the nucleus accumbens produced a place preference for the compartment associated with administered drugs
• lesions to either the nucleus accumbens or the ventral tegmental area blocked the self-administration of addictive drugs or the development of place preferences related to drug use
• elevated dopamine in nucleus accumbens associated with self-administration of drugs and experiencing natural reinforcer

Question 22

Define positive-incentive value

Answer 22

The anticipated pleasure associated with an action (wanting, craving the drug)

Question 23

Define hedonic value

Answer 23

the amount of pleasure that is actually experienced (liking the drug)

Question 24

Describe the incentive-sensitization theory of drug addiction

Answer 24

Drug use becomes a habit in addiction- prone individuals because the positive incentive (wanting the drug) increases with repeated drug use while the hedonic value (liking the drug) does not increase

Question 25

Describe physical dependence theories of addiction. Describe evidence that suggested that this theory is not accurate.

Answer 25

Drug use and addiction to drugs is driven by motivation to avoid withdrawal symptoms that result when one developed physical dependence. This, drug addiction is a vicious cycle of using to avoid the negative effects of not using.

Physical dependence theory is not supported given evidence that, after having been abstinent (and no longer experiencing physical withdrawal symptoms), individuals relapse and begin using drugs again

Question 26

Describe two recent findings that have led to questions about the relevance of studies using self-administration paradigm in rats

Answer 26

1) the housing conditions of rats in self-administration studies are not natural and do not reflect those of humans. Further, they are not offered any other choice as humans are in their daily environment
2) most of this research has focused on stimulants, but this may not tell us about neurotransmitters and brain structures important for other drugs (ex: heroin)

Question 27

As one transitions from initiation of drug use to compulsive drug taking, changes in brain functioning occur, such as

An area of the brain responsible for habit formation, the _____ striatum, is more involved in reacting to drugs and drug-cues than the nucleus ______

Individuals that transition from drug use to habitual use show differences in a brain area associated with self control, the ______ cortex

Answer 27

Dorsal, accumbens

Prefrontal