PT - JOURNAL ARTICLE AU - M Valenzuela TI - O3-4.1 Cognitive lifestyle, dementia protection and the brain's reserve mechanisms AID - 10.1136/jech.2011.142976a.97 DP - 2011 Aug 01 TA - Journal of Epidemiology and Community Health PG - A35--A35 VI - 65 IP - Suppl 1 4099 - http://jech.bmj.com/content/65/Suppl_1/A35.3.short 4100 - http://jech.bmj.com/content/65/Suppl_1/A35.3.full SO - J Epidemiol Community Health2011 Aug 01; 65 AB - Cognitive lifestyle refers to acquired patterns of cognitive and mental activity over the course of one's lifetime, and in our group has been formalised to include information about educational achievement, occupational complexity, social engagement and cognitively-loaded leisure activities. Many large-scale prospective cohort studies have shown that maintaining a more active cognitive lifestyle is linked with a reduction in incident dementia risk. Recently, we have further shown that the combination of a higher educational level with either a more cognitively challenging job in mid-life, or enhanced social activity in later life, is more important for minimising dementia risk than either factor in isolation.Brain reserve and cognitive reserve are typically suggested to mediate this protective relationship. In this presentation, a brief history of the terms will be given, as well as a deconstruction into more specific biological mechanisms. An evaluation of the role of disease modifying, neuroprotective and compensatory mechanisms is then possible, and will be discussed in relation to the design of clinical trials and community-based studies.