12 Clinical Psychology
STEP 4 Review the Knowledge You Need to Score High
Biological psychologists believe that abnormal behavior results from neurochemical imbalances, abnormalities in brain structures, or possibly some genetic predisposition. Treatments, therefore, include psychopharmacotherapy (the use of psychotropic drugs to treat mental disorders), electroconvulsive therapy, and psychosurgery. Medical doctors, psychiatric nurse practitioners, and a limited number of clinical psychologists can prescribe psychoactive drugs. Four major classifications of psychotropic drugs are anxiolytics (antianxiety medications), antidepressants, stimulants, and neuroleptics (antipsychotics).
Anxiolytics, also called tranquilizers and antianxiety drugs, include quick-acting benzodiazepines such as the widely prescribed drugs Valium (diazepam), Librium (chlordiazepoxide), and Xanax (alprazolam) and slow-acting BuSpar (buspirone). Benzodiazepines increase availability of the inhibitory neurotransmitter GABA to the limbic system and reticular activating system where arousal is too high, reducing the anxiety felt by the patient. Other therapies such as visualization, relaxation, and time management can be used in conjunction with drugs so that the drugs may be tapered off over time, because patients can develop unpleasant side effects and build up a tolerance to these compounds. Anxiolytics are helpful in the treatment of post-traumatic stress disorder, panic disorder, agoraphobia, and generalized anxiety disorder.
Antidepressant medications elevate mood by making monoamine neurotransmitters including serotonin, norepinephrine, and/or dopamine more available at the synapse to stimulate postsynaptic neurons. Types of antidepressants include monoamine oxidase inhibitors (MAOIs), which inhibit the effects of chemicals that break down norepinephrine and serotonin; tricyclics, which inhibit reuptake of serotonin; selective serotonin reuptake inhibitors (SSRIs), which inhibit reuptake only of serotonin; and atypical antidepressants (sometimes called non-SSRIs), some of which may inhibit reuptake of serotonin, norepinephrine, and dopamine or a combination of two of them. Commonly advertised SSRls include paroxetine (Paxil), fluoxetine (Prozac), sertraline (Zoloft), citalopram (Celexa, Lexapro), and fluvoxamine (Luvox). Non-SRRIs include bupropion (Wellbutrin) and velafaxine HCL (Effexor XR). They have all been found effective for treating depressive disorders, and some have also been found effective for treating obsessive-compulsive disorder, panic disorder, and post-traumatic stress disorder (PTSD). For treatment of bipolar disorder, lithium has been widely used to stabilize mood, alone or with antidepressants. Anti-seizure medicines used to treat epilepsy, such as valproic acid (Depakene), divalproex (Depakote), and Topiramate (Topamax) have also been used.
Stimulants are psychoactive drugs, such as Ritalin (methylphenidate) and Dexedrine (dextroamphetamine), that activate motivational centers and reduce activity in inhibitory centers of the central nervous system by increasing activity of serotonin, dopamine, and norepinephrine neurotransmitter systems. They are used to treat people with narcolepsy and people with attention-deficit/hyperactivity disorder.
The last class of drugs, neuroleptics, is made up of powerful medicines that lessen agitated behavior, reduce tension, decrease hallucinations and delusions, improve social behavior, and produce better sleep behavior, especially in patients with schizophrenia. An excess of dopamine is thought to be the cause of the schizophrenic symptoms; neuroleptics block dopamine receptors. Neuroleptics include Thorazine (chlorpromazine), Haldol, and Clozaril. Unfortunately, these drugs can have serious side effects, including tardive dyskinesia, or problems with walking as well as drooling and involuntary muscle spasms, which result from the blocking of dopamine at other sites. These problems cause some patients to abandon the medication after hospitalization, which results in a return of psychotic symptoms.
Other Biological Treatments
Some patients do not respond well to antidepressant drugs or psychotherapy. Electroconvulsive shock treatment (ECT) is used as a last resort to treat severely depressed patients. ECT is administered humanely, with the patient under anesthetic and given a muscle relaxant to prevent injury from convulsions. Then the patient receives a momentary electric shock. Typically, the procedure is repeated about six times over 2 weeks. Just how the procedure works is still unknown, but many depressed, suicidal patients are restored to healthy functioning. The patient usually experiences some (often temporary) memory loss immediately following the procedure, but no apparent brain damage. A promising new painless treatment for severe depressive disorder is repetitive transcranial magnetic stimulation (rTMS) in which repeated pulses surge through a magnetic coil positioned above the right eyebrow of the patient. The treatment is administered daily for a few weeks. The treatment may work by stimulating the depressed patient’s left frontal lobe.
Psychosurgery, or the removal of brain tissue, can also be used to treat certain organic problems that lead to abnormal behavior. Psychosurgery is a treatment of last resort because its effects are irreversible. From about 1935 to 1955, the prefrontal lobotomy, which cut the main neural tracts connecting lower brain regions to the frontal lobes, was performed on thousands of patients with schizophrenia, especially violent ones, to reduce the intensity of their emotional responses. Unfortunately, following the lobotomies, many patients were left as emotional zombies, with extensive brain damage. Today, psychosurgery is very limited. One successful procedure used for severe epilepsy is the corpus callosum transection, or split brain surgery, in which only the corpus callosum between the left and right cerebral hemispheres is cut.