EFFECTS OF BRIEF CAFFEINATED-BEVERAGE DEPRIVATION ON MOOD, SYMPTOMS, AND PSYCHOMOTOR PERFORMANCE

The effects of short-term deprivation of caffeinated beverages on mood , withdrawal symptoms, and psychomotor performance were studied in hab itual coffee drinkers. Twenty-four male and female coffee drinkers wer e tested at midday (1130-1330 h) under two conditions. On one day they consumed caffeinated beverages ad lib prior to testing, and on the ot her they remained caffeine abstinent. The order of treatments was coun terbalanced. Mood and withdrawal symptom reports were collected by que stionnaires. Psychomotor performance was tested with a computerized te st battery. Caffeinated-beverage deprivation was associated with decre ased Vigor and increased fatigue and with symptoms including headache. No changes in psychomotor performance were observed. Even short perio ds of caffeinated-beverage deprivation, equivalent in length to missin g regular morning coffee, can produce noticeable unpleasant caffeine-w ithdrawal symptoms by the middle of the day. These symptoms may be a c ommon side effect of habitual caffeinated beverage consumption. (C) 19 97 Elsevier Science Inc.