Effects of Caffeine Withdrawal on Attention in College Students


by David Hurley

The purpose of this research project was to examine the effects that caffeine withdrawal has on attention in the classroom.  Ten caffeine users, who were college students were assessed for mood and attention in the classroom under two conditions; pre-withdrawal from caffeine and post withdrawal.  The measures used were a self-made questionnaire which evaluated their classroom performance and the Profile of Mood States Questionnaire (POMS).  The participants reported to a classroom to fill out these questionnaires and then were asked to abstain from foods containing caffeine.  They came back 48 hours later and filled out the questionnaires.  The findings of this study showed a decrease in attention, retention, note-taking ability, understanding, and focusing in the classroom.  The findings also indicated that the participants were more tired and less vigorous on an overall scale but not in the classroom.  The subjects reported no confusion overall as they did in the classroom.

Acknowledgements
Introduction
Method
Results
Discussion
References

Acknowledgements

    First and for most I would like to thank God for helping me get through this assignment.  Without my faith I would not have come this far.

   I would also like to thank my Mother, Father, and three brothers for being the most supportive people in my life. 
 
    I would like to acknowledge and thank Professor Troisi and Professor McKenna for all of their interest and help throughout this study. 

 
I would like to thank my friends for relieving me of stress during this extremely difficult accomplishment.  Particularly I would like to thank Dave Cannon and my roommate Scott McGinn.  I thank Scott for being tolerant while I stayed up all hours of the night typing when he was trying to sleep.  I thank Dave for his words of wisdom.  Without them, I may have been a lot more

   Lastly I would like to thank all of my participants for taking time out of their hectic schedules to be a part of this project.
 
Back To Top

Introduction

  Over 85% of Americans use the drug daily and the average intake is about 200 mg/day (Hughes, Oliveto, Helzer, Higgins, & Bickel 1992).  However, caffeine users do not think about caffeine withdrawal as much as they should.  Though symptoms are mild in comparison to other drugs, they can have significant effects on people’s lives, specifically on mood and performance.  Caffeine withdrawal can also have significant physiological effects, the most common one being headaches.  The withdrawal that one goes through has an onset of about 12-24 hours, peaks at around 20-48 hours and has duration of one week (Griffiths and Woodson 1988).   

    The effects of caffeine withdrawal among humans living in a residential laboratory were evaluated by Comer, Haney, Foltin, and Fischman in a 1997 study.  Twelve volunteers (ten men and two women) in their twenties and thirties went through a seventeen day study where certain behaviors were measured, such as psychomotor task performance, self-reported mood, social behavior and food intake.  Subjects were maintained on 100 mg of caffeine three times a day except on days 5-6 and days 12-13 where placebo took the place of caffeine (Comer et al., 1997).  This study provided two phases of withdrawal and two phases of habitual use for the observers to analyze.
    The data was analyzed using a three-variable repeated-measures analysis of variance.  The mean value for headaches during the preplacebo stage was 7.3 and during the placebo stage it more than doubled to 15.8 and then went back down to 6.7 in the next preplacebo stage (Comer et al., 1997).  Not only were headaches associated with the placebo stage but feeling miserable, sedated, sleepy, tired, unmotivated, and yawning also increased at this time.  On the other hand, feelings of being alert, anxious, energetic, and self-confident all significantly decreased.  Being alert went from 56.5 down to 49.7 when the placebo was administered (Comer et al., 1997).  This shows the effect that caffeine withdrawal has on mood and motivation.  These effects may interfere with one’s learning in the classroom.   
    The results from this study provide evidence that there is a syndrome related to caffeine withdrawal.  The subjective-effects ratings were consistent with prior studies showing that caffeine withdrawal is associated with decreased levels of alertness and energy, and increased levels of headaches and tiredness (Comer et al., 1997). 
    In a related study (James, 1998) observations showed that performance was significantly impaired when the subjects were withdrawn from the drug.  It also indicates changes in alertness which was significantly worse when withdrawal has taken place.  In this study, 36 habitual caffeine users, both male and female, underwent a double-blind placebo-controlled cross-over design with counterbalancing.  The participants experienced all four conditions involving the ingestion of a placebo or caffeine three times a day for six days followed by a seventh day.  This seventh and final day is called the challenge day because the subjects may receive something different, either a placebo or caffeine.  This process enabled there to be four different groups: caffeine on the first six days and on the challenge day (CC), caffeine and then the placebo (CP), placebo and then the caffeine (PC), and finally the placebo on the first six days and then on the challenge (PP).  This seven-day cycle was repeated three times making the experiment last for one month (James, 1998).

    A Post hoc analysis showed that the CP condition contained subjects who did significantly worse on performance than the average of the other three conditions (James,
1998). Performance was measured by the composite speed/accuracy scores in laboratory sessions.  The CP condition was the only condition where the subjects were withdrawn from the drug and this shows how caffeine withdrawal can significantly worsen one’s psychomotor performance.  Also there was no evidence that caffeine use improved performance.  This was true for the habitual users in the CC group and for acute users in the PC group.  Caffeine only had negative effects on performance when it was withdrawn, not when it was added or maintained, nor did it have positive effects (James, 1998).     
    Regarding alertness, the post hoc analyses showed that it was significantly higher in the PC condition and significantly lower in the CP condition (James, 1998).  This shows that when there was a change there would also be a significant effect.  The CC or the PP conditions did not introduce or take away caffeine so there was no change; hence, caffeine is a psychoactive drug, which can alter one’s mood.  When caffeine was added, that effect was positive but when it was taken away, that effect was negative and people were less alert.  Being alert is extremely important in the classroom and I propose that when withdrawn from caffeine, the students will be less attentive and performance will significantly decrease.
    The DSM-III-R states that caffeine withdrawal was not included because even though there are withdrawal symptoms, they are not severe enough to necessitate clinical attention(Hughes et al., 1992).  However, the DSM IV does include caffeine withdrawal because studies like James’ have shown that it is very severe.  A chi square analysis, which used the PP condition as a baseline, indicated that there was no significance in headache frequency during the PC condition.  However there was a significant increase of frequency for the CP condition. 
    Post hoc analysis showed that the headache duration was significantly longer and more severe in the CP condition when compared to the other three conditions (James, 1998).  
This data provides evidence that caffeine withdrawals cause headaches; however it is the severity of these headaches that needs to be further looked at. 
    In a 1992 study by Silverman, Evans, Strain, and
Griffiths, the severity of caffeine withdrawal was evaluated.  They tried to determine the effects in the general population of habitual users abstaining from caffeine.  They studied 62 normal adults whose caffeine intake was low to moderate with a mean of 250 mg/day which is about two and half cups of coffee.  The subjects completed questionnaires about their symptoms and tests on their mood and performance during their normal diet phase and during the double blind conditions, where they received either a placebo or caffeine tablet (Silverman et al., 1992). 
    During the placebo period subjects reported having moderate or severe headaches (52 percent).  This was significantly more than either of the two baseline periods.  Some had symptoms so severe that the subjects reported using medications to help them even though they were not permitted to (13 percent) (Silverman et al., 1992).  There was a tapping task in which subjects had to tap two hundred times on a key as fast as they could in three consecutive tests, which were about ten seconds apart.  Post hoc test showed that the performance during the placebo stage was significantly slower than the performance during the caffeine and base-line stages.  The profile of mood states actually showed a significantly higher percentage of subjects with abnormal scores (Silverman et al., 1992).   
    The severity of the effects was assessed by comparing the percentage of the subjects with abnormal responses on different measures during all three phases; base-line, placebo, and caffeine consumption.  Post hoc analysis shows that the percentage of the subjects who had moderate to severe headaches (52 percent) was significantly higher than those percentages during the caffeine period (6 percent) and the base-line period (2 percent) (Silverman et al., 1992).  The severity of the low performance for the tapping test was shown by a graph, which displayed the mean for the placebo stage.   This mean was only about 343 taps per minute while the other means for the baseline and caffeine stages were in the 350’s and 360’s (Silverman et al., 1992).  This was a significant difference and shows us again how caffeine hinders one’s psychomotor performance.  If these subjects did significantly worse on this tapping task then maybe the withdrawal will also effect their ability to retain the necessary information during class leading to lower performance. 
    The symptom questionnaires also helped observers assess the severity of these symptoms.  Examples would be some of the comments made during the placebo stage.  One person remarked that their headache was so bad that it progressed into vomiting flu-like symptoms.  Others gave evidence as to how much it affected their performance.  “I couldn’t concentrate, even when I had to do those tests,” (Silverman et al., 1992, p. 1112) remarked one of the subjects.  One of the subjects even came out and said, “I can only compare that sickness to the radiation and treatment [radiation and chemotherapy treatment for cervical cancer] of the past year” (Silverman et al. 1992, p. 1112).  This is a rather bold statement but it shows that the severity of caffeine withdrawal can be much worse than one would think. 
    In 1998, Evans and Griffiths conducted four different double-blind experiments using different participants for each one, which gives us a more parametric analysis of caffeine dosing conditions.  In each experiment, subjects were instructed to report to the research unit twice a day and fill out a questionnaire before taking each capsule, which was either a placebo or caffeine.  However, during experiment 1, they were told to do this a third time in the evening and bring the questionnaire back the next morning.  Either the participants would receive 300 mg all at once and then two placebos or they would receive 100 mg three times a day.  This procedure helped observers assess dosing conditions.  The two forms they filled out where the caffeine withdrawal questionnaire and the Profile of Mood States (POMS) (Evans and Grifiths, 1998).   
    Experiment 1, was a sixty-three day study where fifteen participants would receive caffeine consecutively for five to nine days and a placebo for a period of two days at a time.  After this two-day abstinence, they would again be maintained on caffeine for five to nine days (Evans and Griffiths, 1998).  The ANOVA showed that there was no significant difference between the dosing conditions but there was an extreme difference between the placebo stage and the caffeine stage.  There was an increased rate of headaches, poor mood, tiredness, flu-like symptoms, fatigue, and decreases in vigor, alertness, and friendliness.  These results put together shows that a caffeine withdrawal syndrome occurs whether you take a lot of caffeine once a day or you take it proportionately throughout the day (Evans and Griffiths, 1998).
    
Experiment 2 was called “Caffeine Maintenance Dose,” which was a seventy-three day study and contained seventeen subjects.  The subjects would ingest two capsules a day, which were again either caffeine or placebo.  They were maintained on either 100, 300, or 600 mg of caffeine, each day during the caffeine stage, which was divided up between two capsules.  These subjects would also go through two-day placebo periods after habitually using caffeine for at least seven days.  Between dosing conditions, the subjects would experience an increase or decrease of 100 mg/day until the new maintenance dose was reached (Evans and Griffiths, 1998).  The ANOVA showed that there was significant Drug x Dose interactions.  There was a significant increase associated with headache during the placebo stage and decrease of alertness but there was also significance between the dosing.  The subjects maintained on 600 mg/day had a significantly higher magnitude of the effects than those subjects maintained on 100 mg/day (Evans and Griffiths,1998).  This shows that the severity of the withdrawal syndrome will increase with the amount of dependence.  Who knows how severe it could actually get?      
    Experiment 3 covered the suppression of caffeine withdrawal and was done with eighteen participants over fifty-four days.  Participants started on 300 mg/day for seven days and then would go through a two-day reduction of that dose or a placebo and then they would be back to their 300 mg/day.  There were six different levels of dosing substitutions and all participants went through all six of these dosing substitutions (Evans and Griffiths, 1998).  The ANOVA showed no effect of the drug but it did show that the substitution of lower doses or no doses resulted in withdrawal effects (Evans and Griffiths, 1998).  This further supports the idea that the syndrome is dose-dependent. 
  
    The duration of caffeine exposure was the focus in the fourth and final experiment done by Evans and Griffiths.  This was a sixty-day study where twenty-five participants ingested two capsules a day.  This time the subjects would take a placebo for seven days and then ingest 300 mg for either 1, 3, 7, or 14 days.  All participants were exposed to all the different caffeine durations (Evans and Griffiths, 1998).  Compared with when the subjects were maintained on 300 mg/day,
substitution of the placebo showed significant changes on no scales after a single day of caffeine exposure but with three days of exposure it showed significance on four or more scales (Headache, Headache/Poor Mood, Physical Symptoms, Tiredness, and Fatigue (POMS).  These observations show that a withdrawal syndrome can develop with as little as three days of caffeine exposure (Evans and Griffiths, 1998).      
     Evans and Griffiths covered many areas in these four different experiments, intervals of caffeine dosing, caffeine maintenance dose, suppression of caffeine withdrawal, and duration of caffeine exposure.  These four studies, along with all the other studies, cited in this review, were done with adults in their twenties and thirties.  Most of these people’s addictions could have started back in their college days.  Being a senior in college has let me observe many people using caffeine to help them stay awake and study for tough exams.  However, as with every addiction, withdrawal will catch up to them.  I think this is a problem that many people do not realize.  I observed college students and saw what happened when I took them off caffeine for two days and how much of a problem the withdrawal causes.  Was caffeine really helping these students or was it hurting them?  If one is dependent on a drug then they must go through a withdrawal period.  How is this withdrawal period affecting one's academic peformance?

Back to Top
Method

   
Ten Saint Anselm College participants (4 males and 6 females) between the ages of 18-22 signed up to volunteer in a three-day senior study.  They had the opportunities to volunteer via a sign posted on the Psychology department bulletin board advertising the study.  General Psychology students also had the incentive to be a part of this study because it gave them experimental credit in that class.  However the students did have the option of not doing an experiment and analyzing articles instead.  The institutional review board has accepted this study before and given full permission to conduct the research.  Each participant has given informed consent to the study. 
    A self-made pre questionnaire was distributed to determine the mean amount of caffeine intake between the ten individuals.  Subjects had to consume at least 100 mg/day and no more than 600 mg/day to participate in the study.  To keep this procedure double-blind there were many other dietary questions on this questionnaire that made caffeine consumption seem like only a part of the study (i.e. dairy products, fruits and vegetables, tobacco, and fried foods).  The subjects were told that the purpose of the study is to evaluate the effects that compounds in these different foods and beverages had on human behavior.  They understood that at anytime during this three-day study I may ask them to abstain from something in their diet.  When the experiment was over participants were given a written debriefing statement and told that the
experiment did in fact deal with assessing compounds of food on our behavior.  However the study specifically evaluated the effects of caffeine and the absence of caffeine.
    Use of a within-groups design eliminated many of the difficulties that go along with control.  The same group was observed with a baseline period and an experimental period. During the first day (Monday) the subjects were allowed to go along with their normal “caffeine diet” and recorded what they consumed.  This was the baseline period.  However, they did not perceive it as a “caffeine diet” because I later asked them to abstain from arbitrary foods as well as caffeine. These arbitrary foods were peanut butter, shellfish, and candy.

    During the baseline period I administered two questionnaires assessing their mood and their attentiveness.  One of these questionnaires was a Profile of Mood States.  The other was a self-made questionnaire that dealt with their classroom abilities.  They answered on a scale of 1-5 (5 being “extremely” and 1 being “not at all”).  This questionnaire had questions like “Did you feel focused?” or “Did you understand the Professor?”  There were twelve questions that measured on this questionnaire. 

    Another difficulty that was anticipated to arise was the fact that students may or may not have complied.  I avoided this
by not conducting the experiment during midterm examination week, which was a time when students may have really needed their coffee and may have given in.  This caused only one of the ten subjects to not comply with the study, making it a nine person study.  I also let students know that it is extremely important to be honest about what they consumed and they would not be penalized in any way if they did not comply.  They still received credit in their psychology class for participating in an experiment.    
    The final two days (Tuesday and Wednesday) I gave the participants a slip of paper asking them to abstain from the following foods: coffee, tea, peanut butter, cola, Mountain Dew, Red Bull, shellfish, chocolate, and all other candy.  When they came in Wednesday night I had them circle yes or no to see if they complied or not.  Caffeine intake was the independent variable that was manipulated.  The dependent variable was of course, the subject’s mood and attentiveness during class.  After the second day of withdrawal I administered each questionnaire again.  After they completed these questionnaires the participants received their debriefing statement explaining that this study was done to evaluate the effects of caffeine withdrawal on mood and attentiveness during class.  I told them that it was more than just an experiment looking at the compounds of food’s effects on behavior.  I supplied the participants with a website where they can view the results of the study.  I also reminded them of the poster session in April, where they can come by, view my study, and ask any questions.  When the results were gathered I used a Repeated Measures T test to analyze the data.                  
Back to Top

Results
   
    Twelve factors were measured to determine how caffeine withdrawal affected one’s abilities in the classroom.  Five out of the twelve behaviors were significantly reduced among the nine participants.  Table 1 presents descriptive statistics showing the means and standard deviation of each variable.  It also presents the minimum and maximum score that the variable received from the nine participants.  Figure 1 represents the five variables that were significantly affected by caffeine withdrawal.  These behaviors were one’s ability to focus, retain information, understand the professor, attentiveness, and note taking ability.  All of these behaviors were significant at the .05 level.  The other seven behaviors that were evaluated did not prove to be significantly lower in the caffeine withdrawal condition.  These behaviors include, alertness, ability to stay awake, tiredness, interest in the subject matter, confidence, feeling determined, and feeling that the class was dragging on.
  Therefore caffeine withdrawal did have a negative effect on certain abilities in the classroom in these nine participants.  Furthermore, the behaviors that were affected may be grouped together as well as the behaviors that had no significance. 

Table 1
 
Descriptive Statistics(Mean, Minimum/Maximum, and Standard Deviation).
    

                                                                 Descriptive Statistics

 

N

Minimum

Maximum

Mean

Std. Deviation

AWAKE1

9

2.00

5.00

3.5556

.88192

AWAKE2

9

1.00

5.00

3.0000

1.41421

ALERT1

9

2.00

5.00

3.5556

.88192

ALERT2

9

1.00

5.00

3.1111

1.26930

TIRED1

9

2.00

5.00

3.2222

.97183

TIRED2

9

1.00

4.00

2.4444

1.13039

FOC1

9

3.00

4.00

3.6667

.50000

FOC2

9

2.00

4.00

3.0000

.70711

ATTEN1

9

3.00

5.00

3.7778

.66667

ATTEN2

9

2.00

4.00

3.0000

.70711

INTERES1

9

3.00

5.00

3.7778

.83333

INTERES2

9

1.00

5.00

3.2222

1.39443

RETAIN1

9

3.00

4.00

3.5556

.52705

RETAIN2

9

1.00

5.00

2.6667

1.11803

CONFID1

9

3.00

5.00

3.7778

.66667

CONFID2

9

1.00

5.00

3.2222

1.09291

DETERM1

9

2.00

5.00

3.3333

.86603

DETERM2

9

1.00

5.00

2.7778

1.39443

UNDERST1

9

4.00

5.00

4.3333

.50000

UNDERST2

9

2.00

5.00

3.4444

1.01379

NOTES1

9

3.00

5.00

4.4444

.88192

NOTES2

9

1.00

5.00

3.4444

1.23603

DRAG1

9

2.00

5.00

3.6667

1.11803

DRAG2

9

1.00

4.00

2.4444

1.01379

Valid N (listwise)

9

 

 

 

 


    These results show that every single mean decreased during the caffeine withdrawal condition.  However the p values show which measures significantly decreased.  (Focus = .050, Attentive = .043, Retaining Information = .035, Understanding the Professor = .002, and Note Taking ability = .028).  The other seven measures were above the p value of .05, which makes them insignificant.  These results present a pattern indicating that the variables which were negatively affected share some commonalities.  When the subjects were withdrawn from caffeine the absence did not seem to hinder their interest, confidence or determination.  Moreover their motivation was not significantly affected but their ability to perceive and process the information was reduced.  Figure 1 shows the difference in the means of these significantly lower measures.       


Figure 1
Mean Difference in the significantly decreased measures

(Focusing, attention, retention, understanding, note-taking).

Black (Pre-Withdrawal) White (Post Withdrawal)

image 1

    Though it was harder for the participants to learn they were still determined and interested.  Abstaining from caffeine did not slow the subjects down physically, as it has proven to do so in the past, but it seemed to slow them down mentally.  However, the Profile of Mood States Questionnaire (POMS) had some contradictions.  The POMS indicated that the participants were actually feeling more tired and less vigorous during the withdrawal condition. The six measures in this questionnaire include, tension, depression, anger, vigor, fatigue and confusion.  Only two of these measures fell under the p value of .05.  Figure 2 shows the means of these two significantly decreased and increased measures. 
Figure 2
Mean Difference of the significantly increased fatigue and decreased vigor.

Black (Pre-Withdrawal) White (Post Withdrawal)

           Image 1                 

    The participant’s tiredness was affected on a general scale but not in the classroom.  The POMS also indicated that the participants were not anymore depressed, angry, confused, nor did they have anymore feelings of tension.  This is interesting because they seemed to be confused in the classroom but not on the general scale.  Table 2 shows the means and standard deviations for all of these measures.

Table 2
Descriptive Statistics (Mean, Minimum/Maximum, and Standard Deviation).

Descriptive Statistics

 

N

Minimum

Maximum

Mean

Std. Deviation

TENSION1

9

6.00

17.00

10.4444

4.00347

TENSION2

9

5.00

18.00

11.5556

5.15051

DEPRESS1

9

3.00

25.00

10.7778

8.21246

DEPRESS2

9

.00

23.00

9.4444

8.66186

ANGER1

9

5.00

25.00

11.8889

7.70462

ANGER2

9

1.00

19.00

9.3333

6.50000

VIGOR1

9

9.00

20.00

16.1111

3.37062

VIGOR2

9

1.00

17.00

9.8889

5.01110

FATIGUE1

9

4.00

18.00

10.5556

4.15665

FATIGUE2

9

8.00

17.00

14.2222

2.86259

CONFUSE1

9

4.00

14.00

8.8889

3.68932

CONFUSE2

9

4.00

13.00

8.6667

3.50000

Valid N (listwise)

9

 

 

 



    These data support previous research in that fatigue significantly increased and vigor significantly decreased.  However it does not support previous data that show an increase in depression.
Back to Top

Discussion
     The results found in this study suggest that there should be further exploration of this topic.  The number of participants was an extreme weakness.  This shortage was due to lack of interest in the study and to the fact that one of the participant’s data was not analyzed because she was unable to abstain from caffeine for the required two days.  Nothing could be proven with so few subjects.  However, judging by the results from this study it would be interesting and important to see if they remain constant with a larger sample. 
    With such differences in attention, retaining knowledge, understanding the professor, note taking, and focusing, one could prove that caffeine withdrawal has a serious negative impact on the student’s learning process.  The participants felt that they had a harder time with the ability to learn rather than the willingness to learn.  The participants also felt that they were not anymore tired in the classroom than when they were when consuming caffeine. The class did not seem to drag on at all.  The lack of caffeine was not changing their attitudes.  They were no drained or less willing to learn.  However, it was harder for the participants to learn due to the negative effects of caffeine withdrawal on such variables as retention, attention, taking notes, focusing and understanding.  This was true even though they wanted to learn.  Participants felt that the psychomotor processes of understanding and retaining were the factors that were hindered, not the physical aspects, such as being tired or motivational aspects such as confidence or determination.  Caffeine has been shown to not influence participants’ confidence in their own memory (Kelemen and Creeley (2001).  If the participants psychomotor processes are really being slowed down then current caffeine addicts must be aware that when they go through withdrawal their classroom performance may go down which may result in decreasing grades.
    Caffeine Withdrawal has proven to cause tiredness and have significant negative effects on alertness.  This is shown in James’ study (1998) where the placebo/caffeine condition was the most severe of the measures.  However, in this study there was no sign of either of these happening in the classroom.  There was a sign of the participants feeling more fatigue and less vigorous overall.  These students may be so willing to learn that they suppress these feelings in the classroom.  They may have not even thought about how tired or less alert they were.  The participants may have tried as hard as they could to stay awake and learn but felt that the withdrawal was effecting how they learn.  The fact that they were having a harder time learning could have overshadowed how tired and less vigorous they were in the classroom.  They may have only thought about it outside the classroom.  Another explanation for this could be that the withdrawal effects often peak around 48 hours (Griffiths and Woodson 1998).  This could mean that the tiredness didn’t really settle in until they got to the second night of the study, which was exactly 48 hours after I asked them to abstain.  Maybe if the subjects were to come back a third time, the increase in fatigue and decrease in vigorousness would have been so overbearing that they would have had to report such symptoms in the classroom.
  Headaches, depression, and decreases in arousal are the most valid symptoms of caffeine withdrawal (Hughes et al., 1992).  Two out of the three of these measures remained constant in this study when the subjects took the Profile of Moods States Questionnaire (POMS). Feeling depressed, which did not significantly increase, has also been proven to exist with caffeine withdrawal (James and Crosbie 1987).  Not obtaining significance is again either due to the small sample size, the fact that this part of the withdrawal had not fully set in, or even that they were not withdrawn at all.      
  The participants only felt more confused than normal in the classroom and not on a general level.  This may be due to the fact that the confusion was too minute to recognize on a general scale but when they were trying to learn it was highly noticeable.  It could have been so noticeable that they didn’t even think about it on a general scale, just in terms of how much it was affecting their work. 
    These results may be due to the small sample size.  Not obtaining significance in tiredness in the classroom and depression overall shows that we can not take these results as valid without further study.  Not only could the lack of tiredness be due to a small sample size but it could also mean that these students were not really withdrawn.  Also the likeness of the sample has to be taken into account.  These participants were all obtained from a college population that is predominately Caucasian, upper middle-class, Catholic, between the ages of eighteen and twenty-two, and mostly people who were taking a Psychology class.    Another manipulation that may have taken place was the expectancy rates.  The procedure was kept double blind but there was a question at the end to see if the blind actually worked.  The question asked what they thought the study was really about.  Only one person got the exact idea of what the study was about and wrote “to see the effects of the lack of caffeine on students: personality and ability to concentrate.”  That was the closest anyone came in guessing the purpose of the study.  Six out of the nine participants knew that caffeine was the main ingredient involved and two thought it was a study looking at sugar just as much as caffeine.  One of the participants thought that it was a general study of how food effects mood and alertness, which was what I intended for them to think.
    Further research should continue to look at these twelve measures of classroom performance.  Research should evaluate if one’s psychomotor performance is slowed down and if it actually is harder to understand, interpret, and retain information while in the classroom setting.  This would mean a lot to caffeine addicts.  It may encourage people to not become a caffeine addict or it will provide knowledge to current caffeine addicts as to when a good point to quit would be.  They don’t want to quit and go through withdrawal right before a class that is a review for the final.  If caffeine withdrawal does hinder the psychomotor process then it would be extremely beneficial to know.  People would be able to anticipate not being able to understand and retain if they hadn’t had their caffeine.      

Back to Top
References

<>Comer, S. D., Haney, M., Foltin, R. W., & Fischman, M. W. (1997). Effects of Caffeine Withdrawal on Humans Living in a                  Residential Laboratory. Experimental and Clinica  psychopharmacology, 5, 399-403                                        

Evans, S. M., & Griffiths R.R. (1998). Caffeine Withdrawal: A Parametric Analysis of Caffeine Dosing Conditions. The                         Journal of Pharmacology and Experimental therapeutics, 285-294.

Griffiths, R. R., & Woodson, P. P. (1988). Caffeine physical dependence: a review of human and laboratory animal studies.                  Pharmacology, 94, 437-451.

Hughes, J. R., Alison, O. H., Helner, J. E., Higgins, S. T., & Warren, B. K. (1992). Should Caffeine Abuse, Dependence, or                Withdrawal Be Added to DSM-IV and ICD-10? Am  Psychiatry 149:1, 33-40.

James, J. E. & Crosbie, J. (1987).  Somatic and Psychological Health Implications of Heavy Caffeine use.  British Journal of               Addiction 82, 503-509.               

James, J. E. (1998). Acute and Chronic Effects of Caffeine on Performance, Mood, Headache, and Sleep.                              
           
Neuropsychobiology 38, 32-41

Kelemen, W. L., & Creeley, C. E. (2001). Caffeine (4mg/kg) influences sustained attention and delayed free recall but not                     memory predictions. Hum Psychopharmacol Clin Exp 16, 309-319.

Kelemen, W. L., & Creeley, C. E. (2003). State-Dependant Memory Effects Using Caffeine and Placebo Do Not Extend to                  Metamemory. The Journal of General Psychology 130 (1). 70-86.

Silverman, K., Evans, S. M., Strain, E. C., & Griffiths, R. R. (1992). Withdrawal Syndrome after the Double-Blind Cessation                 of Caffeine Consumption. New England Journal of  Medicine 327, 1109-1114

 

Back to Top
For more information on this topic or to have a copy of the full tesxt email me:  DHurley@anselm.edu





        


 
     <>