doi:10.1136/jme.2005.012575 2006;32;74-78 J. Med. Ethics W Glannon Psychopharmacology and memory http://jme.bmjjournals.com/cgi/content/full/32/2/74Updated information and services can be found at: These include: References http://jme.bmjjournals.com/cgi/content/full/32/2/74#BIBLThis article cites 12 articles, 4 of which can be accessed free at: Rapid responses http://jme.bmjjournals.com/cgi/eletter-submit/32/2/74You can respond to this article at: serviceEmail alertingtop right corner of the article Receive free email alerts when new articles cite this article - sign up in the box at theTopic collections (1402 articles) Other Ethics  Articles on similar topics can be found in the following collections Notes http://www.bmjjournals.com/cgi/reprintformTo order reprints of this article go to: http://www.bmjjournals.com/subscriptions/ go to: Journal of Medical EthicsTo subscribe to on 2 October 2006 jme.bmjjournals.comDownloaded fromNEUROETHICSPsychopharmacology and memoryW Glannon...............................................................................................................................J Med Ethics 2006;32:74–78. doi: 10.1136/jme.2005.012575Psychotropic and other drugs can alter brain mechanismsregulating the formation, storage, and retrieval of differenttypes of memory. These include ‘‘off label’’ uses of existingdrugs and new drugs designed specifically to target theneural bases of memory. This paper discusses the use ofbeta-adrenergic antagonists to prevent or erase non-conscious pathological emotional memories in theamygdala. It also discusses the use of novelpsychopharmacological agents to enhance long termsemantic and short term working memory by alteringstorage and retrieval mechanisms in the hippocampus andprefrontal cortex. Although intervention in the brain to altermemory as therapy or enhancement holds considerablepromise, the long term effects of experimental drugs on thebrain and memory are not known. More studies areneeded to adequately assess the potential benefits and risksof these interventions...................................................................................................Correspondence to:Walter Glannon,Department of Philosophy,University of Calgary,Calgary, Alberta T2N1N4, Canada; [email protected] 20 April 2005In revised form 6 July 2005Accepted for publication8 July 2005.......................Memory is critical to both human survivaland personal identity. Non-consciousemotional memory of fearful or threaten-ing events enables us to recognise and respondappropriately to real threats in the natural andsocial environment. Episodic memory of eventsinvolving personal experience is necessary for thepsychological connectedness and continuity thatgives one the feeling of persisting through timeas the same person. Other forms of memoryinclude non-conscious procedural memory,which enables us to perform basic motor skillsand tasks of daily life, and semantic memory,which enables us to recall and use concepts andfacts. Semantic and episodic memory are twoforms of declarative memory, which enables usto consciously recall facts and events. Workingmemory is a short term version of declarativememory and is involved in such complexcognitive tasks as reasoning and decisionmaking.Recent advances in psychopharmacology areenabling researchers to intervene in emotional,semantic, and working memory systems. In thefirst type of intervention, existing drugs are beingused to block or reverse the process throughwhich non-conscious fearful memories of trau-matic events become pathological and causepost-traumatic stress disorder (PTSD) and simi-lar debilitating mental illnesses. It is becausethey are used to treat mental disorders that thesedrugs are a form of therapy. In the second type ofintervention, drugs are being designed toenhance the formation, storage, and retrievalcapacity of long term semantic and short termworking memory. It is because they are used tostrengthen a capacity considered normal thatthese drugs are a form of enhancement. Theseinterventions hold considerable promise; butthey may also involve pitfalls. Both classes ofdrugs are experimental in the sense that they arebeing developed and used for ‘‘off label’’purposes for which they were not originallydesigned. Because they are experimental, thelong term effects of these novel forms ofpsychopharmacology are unknown. I will discusssome of the potential beneficial and harmfuleffects of psychopharmacology on memory.THERAPEUTIC PSYCHOPHARMACOLOGYAdrenaline is a hormone released by the adrenalmedulla in situations requiring effort to fightagainst or flee from a perceived or real threat. Itis closely related to the other stress hormone,cortisol. Adrenaline is released when the adrenalgland receives a signal from the amygdala in thebrain when this structure senses an externalthreat to a human organism. The amygdala ispart of the brain’s limbic system, which regulatesemotions.12It is one of the most primitive partsof the brain and plays a critical role in ourcapacity to avoid threats and survive. One effectof adrenaline is to embed non-conscious emo-tional memories of fearful or threatening eventsin the amygdala. If emotional memory isembedded too strongly in the amygdala, how-ever, it can produce a heightened fear response toexternal events that is out of proportion to theactual nature of the problems at hand. Becauseemotional memories stored in the amygdala areout of our conscious control, they can be difficultto eradicate or modulate and can adverselyinfluence the nature and content of our beliefs,feelings, and other conscious mental states.Events perceived as stressors or threats cantrigger a chronic fear response that puts thebrain, body, and mind on a constant state ofalert. This describes the pathology and patho-physiology of some forms of depression, anxiety,and the emotionally disturbing flashback mem-ories of traumatic events that characterise PTSD.Some researchers have raised the possibility ofusing a beta-adrenergic antagonist, specificallythe drug propranolol, to treat PTSD. This drugblocks the effects of the hormone norepinephr-ine, levels of which rise in the brain in responseto adrenaline. The aim of using propranololwould be to prevent the embedding of patholo-gical unconscious emotional memories of fearfulevents in the amygdala. Brian Strange andAbbreviations: CREB, cyclic AMP response elementbinding protein; PTSD, post-traumatic