Sabina okwunwa Okenyi, Emmanuel Ifeanyi Eze, Joseph Nwabunwanne Okenyi


This experiment investigated the influence of caffeinated substance on sleep inhibition and mental alertness among undergraduates. Participants were selected using Pittsburgh sleep quality scale (PQSI) and were randomly assigned to the experimental and control conditions. The experimental group ingested 200mg of caffeinated coffee while the control group ingested 200mg of decaffeinated coffee. Following this, participants subjectively given sleepiness and mental alertness using the Stanford sleepless scale (SSS) and the United States Air force school of Aerospace medicine (USAFSAM) mental fatigue. Using MANOVA, the results showed that caffeinated substance effectively inhibited sleep and induced mental alertness without gender differences on caffeinated substance.


caffeinated substance, sleep inhibition, mental alertness.

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Amendola, C., A., Gabriel, J.,O.E., & Lieberman, H;R. (1998) . Caffeine effect on performance and mood are department of age and gender. Nur.NeuroSci 1,269-280.

Benowite, N.L. (1990) Clinical pharmacology of caffeine. Annual review Medi, 41, 277- 288.

Bolton, S & Null, G. (1981). Caffeine psychological Effect, Use and Abuse. Ortho molecular psychiatry, volume to 3, 202 -211.

Bonnet, M.H., Webb, O. (1979). The use of caffeine versus prophylactic naps in sustained performance. Sleep 18, 97-104.

Bremer, F. (1935) Cerveau “Isole” et physiologic du sommeil CR Soc. Biol, 118, 1235- 1241.

Bremert, T. (1977).Cerebral hypoxemic centers Ann Neural. 2,1-6

Buysee, D., J., Reynolds II C.F., Mond, J., H., Berman, S., R &Kupfor, D.J., (1989). The Pittsburgh sleep quality index- 9 new instrument for psychiatric practice and research. Psychiatric Research, 28, 193-213.

Curatolo, P.W. & Robberstson, C. (1983). The Health consequence of caffeine: Review. Ann. Interm. Med, 98,641-653.

Eze, J, E &OMeje, O. (1999). Fundamentals of substance abuse, snap press LTD.

Griffiths, R.R & Mumford, K.G. (1995). Caffeine- a drug of abuse? In E.F. Bloom & J.D. Kuffer (Eds), psychopharmacology. The fourth generation of progress (1699-1713). New York Raven Press.

Hicks, R., A., Reyes, J.R., & Chars, Y. (1983).Daily caffeine use and the sleep of college students.Bulletin of the psychonomic society 21, 24-25.

Institute of Medicine (IOM), (2001), caffeine for the sustainment of mental task performance formulations for military operations, washing, trc: National Academy press.

Jarvis, M., J. (1993). Does caffeine intake enhance levels of cognitive performance? Psychopharmacology, 110, 45-52.

Kamimari, G., H., Joubert, A., Offer-sleffer, R., Santaromana, M.&Eddington, N.,D., (1999). The effect of menstrual cycle on the pharmaco kinetics of caffeine in normal, healthy eumenorrheic females.Eur.I. Clinpharmacol. 55, 445- 449.

Landolt, H., P., Worth, E., Barbely, A., &Dijk, D., T. (1995). Caffeine INTAKE (200MG) in the morning affects human sleep and power spectra at night. Brain research675,67-74.

Leathwood, P.D, Pollet, P. (1982). Diet- Induced mood, changes in normal populations. Journal of psychiatric research 17, 144-154.

Liebierman, H.R. Wurtman, R.J Emde, G.G., Roberts, C. & Coviella, I.L.G. (1987). Effects of low do of caffeine on human performance and mood. Pschopharmacology, 92, 308-312.

Lienart, G.A., & Hubber, H.P. (1966) Differential effects of coffee on speed and power tests. Journal of psycho. 63269- 274.

Rogers, P.J., Richardson, N.J & Dermoncourt, C. (1995). Caffeine use: Is there a net benefit for mood and psychomotor performance? Neurophysiology 31- 195- 199.

Saper, C.B. Chou, TC & Scammell, T.E. (2001). The sleep switch hypothalamic control of sleep and wakefulness. Trends in neuroscience 24: 726- 31.

Searles, G.F. (1994). The effect of dietary caffeine manipulations on blood caffeine, sleep and disturbed behavior Journal of intellectual disability the research38,383-391.

Smith, A. (2002). Effects of caffeine on human behaviour food and chemical Toxicology, 40, 1243- 125.

Tarnopolsky, M.A. (1994). Caffeine and endurance performance Sport med., 18(2), 109-125.

Zwyghuizen- Doorenbos, A., Roehrs, T. A., Lipschietz, L., Timms, V., & Roth, T. (1990).Effect of caffeine in Alertness psychopharmacology, 100,30-39.


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