My thanks to the director and staff of the Natal Road Inspectorate for all their time, assistance, equipment, facilities and interest in conducting the driving tests. Statistical analysis of the data showed that post-test findings could not be attributed to a gender effect.
REVIEW OF THE LITERATlJRE
INTRODUCTION
Assessment of hangover severity is difficult due to the lack of studies examining the effects of post-alcohol impairment on human functioning (Cook 1997), and existing research on hangovers is fraught with methodological problems. According to Finnigan and Hammersley (1992), the literature on the effects of alcohol on human performance is so varied that it would be prudent to identify it.
ALCOHOLIC HANGOVER
Cooper (1976) suggests that many of the symptoms of a hangover can be exacerbated by hypoglycemia in the individual. The authors concluded that rebound and toxic effects play a role in the development of the interoceptive stimulus properties of hangovers.
POSSIBLE MEDICAL IMPLICATIONS OF HANGOVERS
Thus, it seems that hangovers are indeed the result of disturbances in many physiological systems that produce many symptoms in animals and humans. Studies strongly suggest that hangover symptomatology can compromise health performance in some individuals (ibid.). Acute alcohol ingestion appears to cause a difference in the density of the fluid in the cupula of the semicircular canal of the inner ear and the density of the surrounding endolymph, resulting in symptoms of nystagmus, vertigo, and even nausea in some individuals (Money & Myles, 1975). ; Schroeder, 1972).
HANGOVER INTENSITY
Studies examining the intensity of a hangover usually follow the subjective analysis of the individual in the form of a rating scale. In a rating scale 2, the intensity of pallor, tremors, sweating, nystagmus, and vomiting was rated by the observer from 0 to 2, which was used to score the objective signs of a hangover (Ylikahri et al., 1974).
PERFORMANCE EFFECTS OF HANGOVERS
In a study that aimed to correlate alcohol consumption in the previous week and current cognitive deficits on some standard neurological tests, Bowden et al. Studies often contradict each other; for example, Nelson (1959) found no change in the accuracy of hand movements 24 hours after drinking, while Kelly et al. 1970) observed reduced hand steadiness and reaction speed in a similar post-alcohol phase.
TESTS OF PERFORMANCE
- Tracking
When alcohol does not affect perrormance, it is often difficult to determine whether this is due to a true null effect or because the specific version of the specific task was not sufficiently sensitive to the effects of alcohol (ibid.) . Decision-making tasks of some kind have been used most frequently in the study of the effects of alcohol on performance.
MEDIATORS OF THE ALCOHOL-PERFORMANCE RELATIONSHIP
Similarly, there is significant variability in the rate at which alcohol is eliminated from the blood, causing further complications for alcohol elimination. Another problem identified in the literature (Finnigan & Hammersley, 1992) is that the observed effects of alcohol may be partly due to expectancy effects.
AVIATION STUDIES
A number of studies have demonstrated measurable impairment of simulator performance several hours after a peak BAt of 100mg/dl (Cook, 1997; Morrow, Leirer & Yesavage, 1990; Yesavage & Leirer, 1986). They found that more errors were made in reporting heading and altitude over the radio on the ascending rather than on the descending part of the BAL curve, and that some performance decline persisted for eight hours after drinking. Eight hours after a large dose of alcohol, some people may still have elevated BAL, and even after a modest dose, people may be mildly impaired (Finnigan & Hammersiey, 1992). It is of interest to note that in South Africa it is civil.
Aviation authorities support this rule while South African Airways (SAA) is more cautious in setting their "bottle in choke" rule at 12 hours after consuming alcohol.
ALCOHOL AND DRIVING
At a random signal, they performed the difficult maneuver of rapidly swinging the car to the left or right and then steering it between two rows of pylons placed with a minimum tolerance on either side of the car. It was found that 19 of the 22 subjects scored significantly worse under hangover conditions than when not hungover, with an average decrease of 20%. Due to the abundance of studies on 'drinking and driving', it is generally accepted that the risk of being in a car accident increases with alcohol, and increases dramatically with higher doses.
Although less sensitive for alcohol-related disorders, a similar dose-response relationship has been observed for driving. The relative risk of a traffic accident increases exponentially with the driver's BAL, and a BAL as low as 10-40 mg/d is associated with an increased risk (ibid.).
MEASURING BLOOD ALCOHOL LEVELS
- Blood Alcohol Curve
- Breath Alcohol Analysis
The blood alcohol curve (Figure 1) reflects the continuity of changing alcohol concentrations from the moment alcohol is absorbed into the system until the end of excretion. The peak marks the inflection point of the blood alcohol curve at which the rates of absorption and elimination of alcohol from the blood are equal (Schwar, 1976). In cases where the blood alcohol concentration does not change for a certain period of time, the blood alcohol curve can form a plateau (Payne et al., 1966).
Therefore, the amount of alcohol present in deep lung air is proportional to the amount of alcohol in the blood.
CONCLUSION
Mouth alcohol is the term used to refer to the situation where a person has alcohol residue in the mouth. According to the Victoria Police's Informant's Training Manual (1998), a person who has just consumed a drink containing alcohol will result in alcohol residue being left in the mouth. mouth which in turn will have a direct influence on the result of a breath analysis. When tested by breath alcohol analysis, breath samples contaminated with mouth alcohol can cause the breath alcohol concentration to be grossly exceeded, because the alcohol concentration in a drink is much higher than the alcohol. To perform a representative breath alcohol analysis it is essential that only deep lung air is obtained. To prevent a mouth alcohol situation from influencing an analysis, it is necessary to ensure that the person being tested has not consumed alcohol for at least 15 minutes prior to collecting a breath sample.
Studies examining the effects of alcohol impairment suggest that the return of BAL to zero after alcohol does not mean that the individual will immediately return to a state of sober cognition or have an accurate sense of self-confidence about performance (Anderson & Dawson, 1997). The study deals with a previously intoxicated individual who needs resources for attention in the performance of occupational or recreational needs.
METHODOLOGY
SUBJECTS
Two groups of volunteers aged 18 to 29 were given a computer test of simple and complex reaction times and a test of driving skills. All subjects were selected from a predominantly student population with an active recruitment from. To prevent any subject from having traces of alcohol in their systems or its effects, all subjects agreed to abstain from consuming alcohol in any form for 48 hours prior to the pretest. All subjects were required to be present at a social evening in a pub, the only stipulation being that subjects in the control group drank soft drinks and no alcohol, while the cat group drank alcohol.
Those individuals from the hangover group who did not reach the stipulated minimum level of ,mg/dl alcohol by 12:00.
MATERIALS AND MEASURES
The purpose of this test is to examine the driver's ability to judge the width of any part of the vehicle. The CALCAP program was selected for the reliability and validity of the program, based on the task development and normative data described in the program manual (Miller, 1986). Subjects are only asked to press the spacebar key when they see two of the same numbers in a row, e.g.
Subjects must press the spacebar key when they see a specific word, e.g. SEVEN' in the center of the screen.
PROCEDURE
Control and experimental groups were pre- and post-tested over the course of the study. When the subjects finished (e.g., the CALCAP test), they would transfer to the alternate location and complete the remainder of the required tests (e.g., the driving skills test), and vice versa. Due to the self-explanatory nature of the software program, subjects were told to follow the on-screen instructions and ask for help when necessary.
In addition, all subjects (N=63) were instructed not to self-treat possible hangover symptoms with medications, due to the possible psychoactive effects that could affect driving ability and reaction time.
DATA ANALYSIS
RESULTS
- HANGOVER SYMPTOMS
- DRIVING MEASURES
- COMPUTERIZED REACTION TIME MEASURES (CALCAP)
- CORRELATIONS ANALYSIS
- ANALYSIS OF COYARIANCE (ANCOVAS)
- BLOOD ALCOHOL READINGS
- GLUCOSE TESTS
- GENDER DIFFERENCES
The results show that the control group, as opposed to the cat group, scored a greater improvement from the pre-test to the post-test. Although most of the CALCAP scores described in Table 7 fell from pretest to posttest and did not reach statistical significance, the control group's scores showed less deterioration than the Hangover group's on the language discrimination test. A more specific comparison in terms of magnitude of change in significant scores found for CALCAP True Positive scores, target driving task, and overall driving assessment is presented in Table 9.
CALCAP True Positive task, while the experimental group only improved by 2.44 %. Furthermore, the table describes an improvement of 2.18°;0 by the control group in the Target Management Test pre- and post-test scores, while the hangover group weakened by 22%.
VARIABLE NO. OF MEAN SO CASES
DISCUSSION AND CONCLUSION
- DEMOGRAPHIC DATA OBTAINED FROM THE INTAKE QUESTIONNAIRE
- HANGOVER SYMPTOMS
- DRIVING MEASURES
- COMPUTERISED REACTION TIME l\'lEASlJRES
- CORRELATIONS ANALYSIS AND ANCOVAS
- GENDER DIFFERENCES
- LIMITATIONS OF THE CURRENT STUDY AND FURTHER RECOMMENDATIONS
- CONCLUSION
The subjective symptoms mostly reported by subjects in the Hangover group reflect aspects of perceived level of physiological distress measured 14 - 16 hours after cessation of drinking. Furthermore, although the data analysis showed few overall significant differences between the groups, it is interesting to note that there was a definite tendency for subjects from the control group to improve on the post-test scores, while the opposite tendency occurred in the hangover group. An important weakness in the design of the study lies in the selection of subjects to groups.
It has already been mentioned that the demographic information collected by the intake questionnaire lacked detail and clarity in the Drinking History category.
INTAKE QUESTIONNAIRE
RESEARCH QUESTIONNAIRE
- HAVE YOU USED PSYCHIATRIC MEDICATION IN THE LAST SIX MONTHS, ego SLEEPING TABLETS OR ANTI-DEPRESSANTS?
- EXCESSIVE THIRST 6. EXCESSIVE HUNGER
- UNSTEADINESS IN STANDING OR GAIT 11. PROFUSE SWEATING
- SHAKINESS
- FATIGUE 16. DIAPHORESIS
- MOOD CHANGE I GRUMPY 19. GENERAL DISCOMFORT
HAVE YOU USED PSYCHIATRIC MEDICATION IN THE PAST 6 MONTHS, ego SLEEPING TABLETS OR ANTI-DEPRESSANTS. HAVE YOU USED ANY ILLEGAL SUBSTANCE IN THE LAST TWO 5. HAVE YOU USED ANY ILLEGAL SUBSTANCE IN THE LAST TWO.
LIGHT MOTOR VEHICLE TEST
FORWARD MOVEMENT
WIDTH ESTIMATION
TARGET
WINDING LINE
SERPENTINE
A STUDY ON THE NEUROPSYCHOLOGICAL CORRELATES OF ALCOHOLIC HANGOVER
CONSENT FORM
A STUDY ON THE NEUROLOGICAL CORRELATES OF ALCOHOLIC HANGOVER
VERY IMPORTANT REQUIREMENTS
ANSWER ALL QUESTIONS ABSOLUTELY TRUTHFULLY, REMEMBER THAT INFORMATION IS GATHERED ONLY FOR THE PURPOSE OF
WHETHER YOU ARE PART OF THE SUBJECT OR CONTROL GROUP, YOU MUST NOT CONSUME ANY ALCOHOL WHAT-SO-EVER FOR
IN THE INITIAL 48 HOUR PRE-TEST PHASE, ALL PARICIPANTS ARE REQUIRED TO ENSURE THAT THEY EAT WELL-BALANCED NON-
THE TEST WILL RUN AS FOLLOWS
TRANSPORT HOME WILL BE PROVIDED FOR THE SUBJECT GROUP AFTER DRINKING, AND IT IS THEREFORE REQUESTED, THAT ALL
