Rapid advances in technology have led to vast knowledge about the structure and functions of different parts of the brain. Each hemisphere has four parts or lobes, the parietal, occipital, temporal and frontal lobes that govern specific functions of the brain . Split-brain research has allowed us to understand more about the way sensory and motor information is routed to and from the left and right hemispheres. Hormones regulate metabolic rate, reproduction and bodily growth and are often active in emotional arousal. Common negative side effects are increased blood pressure and heart rate, insomnia, restlessness, irritability, anxiety, paranoia.
Typical effects are disinhibition, drowsiness, tension reduction, relaxation.
Problematic side effects can be impaired motor and mental functioning and emotional swings. An overdose can lead to loss of consciousness, convulsions, coma or death. However narcotics, like sedatives and stimulants, lead to both psychological and physiological addiction with long-term use. Long-term effects can lead to psychosis as the hallucinations, delusions and perceptual distortions become more extreme and the person can no longer distinguish delusions from reality. The overall success rate is high but side effects such as faintness, restlessness and trembling remain problematic side effects for many patients.