RESUMEN
The relationship between hand preference and duration of sleep was assessed in 40 healthy subjects using self-report estimates, sleep diaries, and wrist activity monitors during an uncontrolled 7-day at-home phase and during a controlled overnight stay in a sleep laboratory. Handedness was unrelated to any index of sleep duration when assessed in the unregulated home environment. In the controlled environment of the laboratory, however, greater right-hand dominance was positively correlated with more minutes of obtained sleep and greater sleep efficiency. Findings were consistent with previous reports which suggest measures of brain lateralization may be related to sleep and health but further suggest that these relationships may be easily obscured by extraneous environmental factors when assessed in an uncontrolled setting.
Asunto(s)
Ambiente Controlado , Lateralidad Funcional/fisiología , Sueño/fisiología , Actigrafía , Adulto , Femenino , Humanos , Masculino , Encuestas y Cuestionarios , Vigilia/fisiologíaRESUMEN
Prolonged sleep loss impairs alertness, vigilance and some higher-order cognitive and affective capacities. Some deficits can be temporarily reversed by stimulant medications including caffeine, dextroamphetamine, and modafinil. To date, only one study has directly compared the effectiveness of these three compounds and specified the doses at which all were equally effective in restoring alertness and vigilance following 64 h of wakefulness. The present study compared the effectiveness of these same three stimulants/doses following a less extreme period of sleep loss (i.e., 44 h). Fifty-three healthy adults received a single dose of modafinil 400 mg (n = 11), dextroamphetamine 20 mg (n = 16), caffeine 600 mg (n = 12), or placebo (n = 14) after 44 h of continuous wakefulness. After 61 h of being awake, participants obtained 12 h of recovery sleep. Psychomotor vigilance was assessed bi-hourly during waking and following recovery sleep. Relative to placebo, all three stimulants were equally effective in restoring psychomotor vigilance test speed and reducing lapses, although the duration of action was shortest for caffeine and longest for dextroamphetamine. At these doses, caffeine was associated with the highest percentage of subjectively reported side-effects while modafinil did not differ significantly from placebo. Subsequent recovery sleep was adversely affected in the dextroamphetamine group, but none of the stimulants had deleterious effects on postrecovery performance. Decisions regarding stimulant selection should be made with consideration of how factors such as duration of action, potential side-effects, and subsequent disruption of recovery sleep may interact with the demands of a particular operational environment.
Asunto(s)
Nivel de Alerta/efectos de los fármacos , Atención/efectos de los fármacos , Compuestos de Bencidrilo/farmacología , Cafeína/farmacología , Estimulantes del Sistema Nervioso Central/farmacología , Dextroanfetamina/farmacología , Desempeño Psicomotor/efectos de los fármacos , Privación de Sueño/psicología , Vigilia/efectos de los fármacos , Adolescente , Adulto , Compuestos de Bencidrilo/efectos adversos , Cafeína/efectos adversos , Estimulantes del Sistema Nervioso Central/efectos adversos , Computadoras de Mano , Dextroanfetamina/efectos adversos , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Masculino , Modafinilo , Polisomnografía/efectos de los fármacos , Tiempo de Reacción/efectos de los fármacos , Sueño/efectos de los fármacos , Adulto JovenRESUMEN
BACKGROUND AND PURPOSE: Insufficient sleep can adversely affect a variety of cognitive abilities, ranging from simple alertness to higher-order executive functions. Although the effects of sleep loss on mood and cognition are well documented, there have been no controlled studies examining its effects on perceived emotional intelligence (EQ) and constructive thinking, abilities that require the integration of affect and cognition and are central to adaptive functioning. PATIENTS AND METHODS: Twenty-six healthy volunteers completed the Bar-On Emotional Quotient Inventory (EQi) and the Constructive Thinking Inventory (CTI) at rested baseline and again after 55.5 and 58 h of continuous wakefulness, respectively. RESULTS: Relative to baseline, sleep deprivation was associated with lower scores on Total EQ (decreased global emotional intelligence), Intrapersonal functioning (reduced self-regard, assertiveness, sense of independence, and self-actualization), Interpersonal functioning (reduced empathy toward others and quality of interpersonal relationships), Stress Management skills (reduced impulse control and difficulty with delay of gratification), and Behavioral Coping (reduced positive thinking and action orientation). Esoteric Thinking (greater reliance on formal superstitions and magical thinking processes) was increased. CONCLUSIONS: These findings are consistent with the neurobehavioral model suggesting that sleep loss produces temporary changes in cerebral metabolism, cognition, emotion, and behavior consistent with mild prefrontal lobe dysfunction.
Asunto(s)
Adaptación Psicológica , Concienciación , Emociones , Solución de Problemas , Privación de Sueño/psicología , Pensamiento , Adaptación Psicológica/efectos de los fármacos , Adolescente , Adulto , Asertividad , Cafeína/administración & dosificación , Cultura , Mecanismos de Defensa , Método Doble Ciego , Empatía , Femenino , Humanos , Control Interno-Externo , Relaciones Interpersonales , Masculino , Inventario de Personalidad , Solución de Problemas/efectos de los fármacos , Autoimagen , Privación de Sueño/tratamiento farmacológico , Supersticiones/psicología , Adulto JovenRESUMEN
INTRODUCTION: Recent research indicates that sleep deprivation impairs decision making. However, it is unknown to what extent such deficits are exacerbated in a dose-response manner by increasing levels of sleepiness, and the extent to which such sleep-loss-induced deficits can be reversed by caffeine. METHODS: At three time points, 26 healthy subjects completed alternate forms of the Iowa Gambling Task (IGT): rested baseline, 51 h awake, and 75 h awake. Every 2 h each night, 12 volunteers also received 4 200-mg doses of caffeine, with the last dose occurring 3 h prior to the IGT. RESULTS: At baseline, volunteers readily learned to avoid disadvantageous high-risk card decks while progressively choosing more frequently from advantageous low-risk card decks. When sleep deprived, however, these same subjects showed impaired performance, choosing more frequently from the disadvantageous high-risk card decks, particularly during the latter half of the game. Contrary to expectations, the severity of performance impairment did not increase significantly from 51 to 75 h of wakefulness, and caffeine had no significant effects on IGT performance during sleep deprivation. DISCUSSION AND CONCLUSIONS: As a provisional extension of our previous study, these preliminary findings further suggest that the ability to integrate emotion with cognition to guide decision making, a capacity believed to be mediated by the ventromedial prefrontal cortex, may be particularly vulnerable to sleep loss. Moreover, these capacities may not be significantly improved by moderate doses of caffeine, suggesting that they may function separately from simple arousal and alertness systems.