The anatomy of a clinical trial

Cognition is the mental process by which an individual acquires knowledge a nd understanding of their physical, cultural, social and psychological worl d. The cognitive system not only endows awareness of the present situation, but also, via the processes of memory, a recollection of previous events a nd experiences. Current perceptions can be used either as a basis to modify and adapt existing mental organisations (schemata) or simply be assimilate d into the pre-existing neural circuits. Under these latter circumstances, the individual's cognisance of this world would not change, whereas, if a p articular schema was accommodated and altered in some way to take account o f a new experience then the individual world view would necessarily change. A psychologically mature and well-adapted person will have schemata, which are in accord with the events and experiences of his psyche-social world. T he correlation between internal cognitive structures and psychological vale nces and relationships in the external environment will be high. On the other hand, the anxious patient will have but a poor correlation bet ween cognitive structures and life events and experiences. The reason for t his cognitive failure could be because of either inherent predisposition or an inappropriate perception of the current world as it is, or am admixture of the two. Whatever the underlying cause; be it a genetic trait or suscep tibility, or faulty state of perceiving; the net result is a progressive br eakdown of the integrity of the cognitive system with the subject exhibitin g symptoms of uncertainty, apprehension, distress and a diminished cognitiv e ability leading to erroneous perceptions and judgements about the future. The anxiety is a direct product of a failure to understand. The afflicted p erson is not able to organise present experiences into existing structures and seemingly not able to utilise previously formed schemata with a proven adaptive value. Anxiety states are amenable to treatment via cognitive therapy, which in it self could seem to confirm the malleable nature of the cognitive system and its role as an essential element in determining a person's psychological i ntegrity. If psychoactive medication is to be used for more than a symptomatic relief of the various manifestations of anxiety, both physical and psychological, then such medications must respect the cognitive system. Neither should th ey impair memory, perception, psychomotor and arousal systems, for otherwis e the patient will be cognitively compromised and therapeutic efficiency re duced or even abolished. Illustrations of the effects of a range of anti-anxiety agents on various a spects of cognition, memory and information processing in both patient and volunteer populations will be used to help identify those medications with genuine anxiolytic (i.e. lowering anxiety without sedation) potential. A pr otocol for clinical trials of putative anxiolytics will be introduced and c linically described. Copyright (C) 1999 John Wiley & Sons, Ltd.