Drug treatments

Drugs that are used to treat anxiety are called anxiolytic (-lytic comes from the Greek "lysis"; which means loosen). The most commonly used anxiolytics belong to a class of compounds called benzodiazepines.

Benzodiazepines

Benzodiazepines are a type of minor tranquilizer, which reduce anxiety and promote calmness and relaxation by depressing the central nervous system. In addition to reducing anxiety, benzodiazepines promote sleepiness and, therefore, are sometimes prescribed to treat insomnia. The most commonly used benzodiazepine is diazepam (Valium).

Research on rats has suggested that benzodiazepines do not reduce anxiety by merely reducing awareness, they seem to actually reduce fear and anxiety directly: Sepinwall (1983) used a technique called the conflict test where a rat is placed in a skinner box with a lever that dispenses food pellets, but also simultaneously gives the rat an electric shock to the feet. Usually, rats will choose not to press the lever; however if they are treated with benzodiazepines, they will press the lever.

Benzodiazepines do not increase hunger or reduce pain, so this indicates that benzodiazepines actually reduce anxiety; the rats are aware that they will be shocked, but they no longer fear it. If the rats lacked awareness they would not press the lever to obtain the food pellet.

The conflict test is now used to test potential anxiolytic drugs, because it has been shown to be successful in identifying drugs that reduce anxiety in humans.

Evaluation of the Use of Drugs to Manage Stress

The use of drugs to manage stress is sometimes appropriate; however, this method only deals with the emotions caused by the stressor, it does not deal with the problem itself. Nevertheless, drugs are useful when it is impossible to remove the stressful situation.

A difficulty with the use of benzodiazepines to manage stress is that they produce side effects, such as psychomotor retardation, Memory Impairment, paradoxical behavioural disinhibition, Depression and emotional blunting, and they can have toxic interactions with other drugs.

Another problem with benzodiazepines is that patients can develop a tolerance and physical dependence on them. This means that they are addictive.

The following video clip shows a man who is suffering from the withdrawl symptoms of benzodiazepines:

Biofeedback

Biofeedback is a general term for any of several techniques that involve providing the user with information regarding their physiological state. Enabling a person to monitor their own physiological arousal in real-time allows the user to develop control over it. Nevertheless, biofeedback equipment is often expensive. Biofeedback techniques include: Galvanic Skin Response, Peripheral Skin Temperature, Electroencephalography (EEG), Electromyogram (EMG) and Heart Rate Variability (HRV)

Galvanic Skin Response Biofeedback

Galvanic skin response biofeedback techniques rely on the changes in the electrical conductivity of the skin during emotional arousal. Increases in anxiety are usually accompanied by increases in the activity of the sweat glands, which is why you may get sweaty hands when you are nervous. As salty water is a very good conductor of electricity, this means that the conductance of the skin increases with anxiety and decreases with relaxation. These changes are measured by placing electrodes in contact with the skin and passing a small current through it. The user of this type of biofeedback equipment attempts to control a tone (high pitch = tension, low pitch = relaxation) or may receive visual feedback through an oscilloscope or computer display.

Useful teaching resource: GSR2 Biofeedback Monitor

Peripheral Skin Temperature Biofeedback

"Peripheral skin temperature" refers to the temperature of the skin in the outermost parts of the body (peripheral = outermost parts). In biofeedback devices it is often measured using a probe attached to the fingers. When a person is relaxed there is greater vasodilation (opening of the blood vessels), which means that there is higher temperature in the skin. Stress causes vasoconstriction which reduces bloodflow and lowers temperature in the skin. By responding to visual or auditory feedback of temperature changes, the user of this type of biofeedback equipment learns to relax by increasing the temperature of their hand. This is probably the least expensive method of biofeedback, as a cheap thermometer (without a kink) can be used to provide feedback.

Electroencepalograph (EEG) Biofeedback

An EEG involves placing electrodes on a person’s scalp to record the small changes in electrical activity of the brain. These changes are displayed on an oscilloscope or computer screen. EEGs are often used to measure changes in brain activity during the different stages of sleep; however, in biofeedback EEG is used to give visual feedback of the activity of the waking brain. When a person is awake and active the eeg trace shows very high frequency (fast) waves with a low amplitude (height of the wave), this is called beta activity; however, when a person is relaxed (or drowsy) the waves become lower in frequency and the amplitude increases, this is called alpha activity. EEG biofeedback can be used to combat stress when a person learns to reduce the frequency and increase the amplitude of the EEG trace.

Electromyogram Biofeedback

Electromyogram biofeedback involves receiving feedback on the state of tension of muscles by measuring their electrical activity. Electrodes are placed on the skin over the muscles to be monitored, typically on the forehead (frowning muscles), shoulders (hunching) or the jaw (teeth clenching). The user is notified of an increase in the tension of these muscles by a light or a sound.

Heartrate Variability Biofeedback

Heartrate variability biofeedback devices monitor the variation in heartrate that occurs on a beat to beat basis. A normal relaxed state heartbeat is not constant, the time inbetween beats vary slightly; however, when a person is in a state of stress their heartbeats become more constant. Heartrate variability biofeedback gives the user feedback on the variability of their heartrate so that they can learn to increase its variability.

Evaluation of Biofeedback

Yucha et al (2001) carried out a meta-analysis of studies between 1975 and 1996 investigating biofeedback as a method of relieving hypertension (high blood pressure). The meta-analysis showed that biofeedback is more effective than no treatment and also more effective than placebo treatments in reducing both systolic blood pressure and diastolic blood pressure. Nevertheless, when compared to other active interventions, such as muscle relaxation and meditation there was no significant difference in systolic or diastolic blood pressure.