Making decisions is such a regular activity that it is mostly taken for granted. However, damage or abnormality in the areas of the brain involved in decision-making can severely affect personality and the ability to manage even simple tasks.

Here, Barbara Sahakian and Jamie Nicole LaBuzetta discuss the process of normal decision making - our strategies for making decisions, biases that affect us, and influential factors - and then describe the abnormal patterns found in patients with conditions such as severe depression, Alzheimer's, and accidental brain damage.

Using striking examples and case studies from their own research to show the impact of abnormal decision making, they introduce the concept of 'hot' and 'cold' decision making based on the level of emotions involved, showing that in various psychiatric conditions extreme emotions alter the pattern of decision making.

Looking at the ways in which the brain can be manipulated to improve cognitive function in these patients, they consider the use of 'smart drugs' that alleviate these problems. The realization that smart drugs can improve cognitive abilities in healthy people has led to growing general use, with drugs easily available via the Internet. They raise ethical questions about the availability of these drugs for cognitive enhancement, in the hope of informing public debate about an increasingly important issue.

About the Author:
Barbara Sahakian, University of Cambridge School of Clinical Medicine, Department of Clinical Neuropsychology, Cambridge, Jamie Nicole LaBuzetta, University of Cambridge, Department of Psychiatry and MRC/Wellcome Trust

Barbara J Sahakian is a world-renowned researcher in the fields of neurology and psychiatry, and is currently based at University of Cambridge School of Clinical Medicine in the Department of Clinical Neuropsychology. She is co-inventor of the CANTAB computerised neuropsychological tests, which are in use world-wide. She is probably best known for her research work on cognition and depression, cognitive enhancement using pharmacological treatments, neuroethics and early detection of Alzheimer's disease. She has over 300 publications covering these topics in various journals including Science, Nature Neuroscience, The Lancet, British Medical Journal, Archives of General Psychiatry, American Journal of Psychiatry, Biological Psychiatry, The Journal of Neuroscience, Brain, Psychopharmacology, and Psychological Medicine. In recognition of her contribution to cognitive neuroscience, she was elected a Fellow of the Academy of Medical Sciences in 2004.

Jamie Nicole LaBuzetta received her medical degree from UCSD, and is currently in the midst of her residency training at the Harvard-affiliated hospitals in Boston, USA. She is a neurology resident at the Partners program (Massachusetts General and Brigham and Women's, two of the Harvard-affiliated hospitals). Her current academic interests are in neurocritical care and neuroethics, and she was recently co-author of an article discussing ethical issues involved in consenting vulnerable patients for neuroscientific research.