This book is primarily concerned with biochemical, behavioural and social influences which affect the function of the mind. The majority of human societies incorporate the use of drugs, legally or illegally, which influence mental activity. These may be used to alter and enhance aspects of mental function or to diminish activity and so reduce tensions or the appreciation of problems. Chapters are included that deal with all the major groups of drugs which are misused, that is hypnotics, tranquilisers, stimulants, euphoriants such as alcohol and organic solvents, hallucinogens and narcotics. Many of these drugs, by virtue of interfering with the biochemistry of the brain, mimic or induce behaviours which are considered to be outside the limits of mental health.

Although not getting the major publicity, alcohol is the main problem drug in most developed countries and, because of Western influence, also in many less-developed societies. The biological basis of the effects of alcohol on the human body is described and the medical and social problems arising from alcohol misuse are discussed. The chapters following this consider the control of alcohol consumption and the help which is available for problem drinkers.

The final chapters are concerned with the main forms of mental illness prevalent in Western society and a survey of the changing pattern of care for the mentally ill in the United Kingdom.