ABSTRACT
Introduction 86
Cognitive Aging 86
Caffeine Consumption Habits and Age 87
Caffeine Intake and Age-Related Differences in Cognitive Function 88
Habitual Caffeine Intake Studies 89
Caffeine, Age, and Arousal 91
Acute Caffeine Effects in Older Persons 93
References 94
INTRODUCTION
The use of caffeine-containing drinks and food is a widespread habit in our modern culture. In Western societies people tend to start regular consumption of coffee or black tea before adulthood, and the total amount of intake remains relatively stable until old age (Hameleers et al., 2000). It is well established that caffeine, the main psychoactive ingredient present in these beverages, has a mild stimulating effect on the central nervous system (Smith, 2002a). Acute effects of caffeine have typically been documented in the domains of vigilance, (selective) attention, and information processing speed (Riedel and Jolles, 1996). The acute effects of caffeine are related to the adenosine-A1 and A2A antagonism of caffeine in the brain, which in turn stimulates the release and turnover of several central neurotransmitter substances, including acetylcholine and noradrenaline (Nehlig et al., 1992; Fredholm et al., 1999). The distribution of adenosine receptors is widespread in the human brain, but receptor sites are particularly abundant in some areas that are involved in higher-order processes (e.g., the hippocampus, a brain structure that is critical for memory formation).
