Individual Differences in Alcohol Effects Among High- and LowImpulsive Sensation Seekers
Kelly, T.H., Robbins, G., Martin, C.A., Marczinski, C.A. and Fillmore, M.T.
Departments of Behavioral Science, Psychiatry and Psychology,University of Kentucky
Abstract
Method
Table 1
Daily Schedule
Time (Min) Event
00
Intake Assessment
Baseline Session
Dose Administration
30
Ascending Session
75/90
Descending Session
Discharge Assessment
Session Tasks
Addiction Research Center Inventory (ARCI): The 49-item short form of the truefalse ARCI provided reports of drug effects on five scales: LSD, Amphetamine (A),
Benzedrine (BG), Morphine-Benzedrine (MBG) and Pentobarbital, Chlorpromazine,
Alcohol Group (PCAG).
Visual-Analog Rating Scales (VAS): Ratings of Stimulated, Sedated, Light-Headed,
Drug Effect and Like Effect were obtained by placing marks on a 100-unit line anchored
with "Not at all" on the left and "Extremely" on the right.
Alcohol Sedation-Stimulation Scale (ASSS): Composite scores for Sedation and
Stimulation were obtained by summation of ratings from 14 adjectives on a scale from 0
to 10 with 0 being “Not at all” and 10 being “Extremely”
Digit-Symbol Substitution Task (2 minutes): Nine random 3-row by 3-column
arrays of asterisks and dashes (one asterisk per row), labeled 1-9 from left to right, were
displayed at the top of the computer monitor. A randomly generated number, between 1
and 9, was displayed in the center of the monitor, indicating which of the nine arrays
should be reproduced on a given trial. Subjects reproduced an array by pressing the
buttons on a 3-row by 3-column keypad that corresponded to the positions of the
asterisks in the screen array.
Rapid Information Processing Task (RIP, 5 minutes): Single digits were presented
in the center of the monitor, and subjects were instructed to press a key whenever three
consecutive even or odd digits were presented. Following correct responses, the speed
of digit presentation was increased, and following incorrect responses or missed signals,
the speed of digit presentation was decreased.
Cued Reaction Time (Cued RT, 15 minutes): Subjects are required to respond as
quickly as possible when green rectangles are presented on the screen, and to make no
response when blue rectangles are presented. Horizontal and vertical white rectangles
predicting the subsequent color presentation on 60% of trials were presented prior to the
color cue.
Cardiovascular: Heart rate and blood pressure were recorded immediately after
completing computer tasks.
Table 2
Breath Alcohol Level
Low Sensation Seekers
High Sensation Seekers
Ascending
Descending
Acsending
Desending
0.45 g/kg
0.052 (.0028)
0.042 (.0015)
0.051 (.0025)
0.039 (.0023)
0.65 g/kg
0.067 (.0039)
0.062 (.0029)
0.072 (.0063)
0.061 (.0025)
Significant Sensation-Seeking Status x Alcohol x Time Interactions
Figure 1 presents the effects of alcohol on VAS ratings of Light-Headed separately for low
and high sensation seekers. Significant alcohol x time interactions were observed for both
low and high sensation seekers, although the magnitude of drug effect was clearly greater
for high sensation seekers. Significant sensation seeking status x time interactions were
observed at the 0.45 and 0.65 g/kg dose conditions. Significant sensation-seeking x alcohol
dose interactions occurred during both ascending and descending level sessions, although
the magnitude of the interaction was clearly greater during ascending level sessions.
Figure 2 presents the effects of alcohol on the ASSS composite Sedated scale separately
for low and high sensation seekers. Significant alcohol x time interactions were observed
for both low and high sensation seekers, although the magnitude of drug effect was clearly
greater for high sensation seekers. Significant sensation seeking status x time interactions
were observed at all dose conditions. Significant sensation-seeking x alcohol dose
interactions occurred during both ascending and descending level sessions.
Significant sensation-seeking status x dose x time interactions were also obtained on VAS
ratings of Stressed and Anxious (data not shown). For VAS Stressed, significant alcohol x
time interactions were observed for both low and high sensation seekers; significant
sensation seeking status x time interactions were observed at the 0.45 and 0.65 g/kg dose
conditions, and significant sensation-seeking x alcohol dose interactions occurred during
both baseline and descending level sessions, with alcohol effects being greater among low
sensation seekers. For VAS Anxious, significant alcohol x time interactions were observed
for both low and high sensation seekers; significant sensation seeking status x time
interactions were observed at at the 0.45 and 0.65 g/kg dose conditions, and significant
sensation-seeking x alcohol dose interactions occurred during baseline, ascending and
descending level sessions, with alcohol effects being greater among low sensation seekers.
No group differences in drug use or other psychiatric symptoms, including conduct
disorder, ADHD, depression or scores on the BSI, were observed.
Alcohol g/kg
0.00
0.45
0.65
Baseline
ARCI
PCAG
0.00 g/kg
0.45 g/kg
0.65 g/kg
A
0.00 g/kg
0.45 g/kg
0.65 g/kg
LSD
0.00 g/kg
0.45 g/kg
0.65 g/kg
25
20
20
Rating
Low Sensation Seekers
30
30
15
15
10
10
5
5
0
0
Baseline
Acsending
Descending
Baseline
Ascending
Descending
Low Sensation Seekers
25
25
20
High Sensation Seekers
Alcohol g/kg
0.00
0.45
0.65
15
15
10
5
5
0
0
Baseline
Ascending
Descending
Baseline
Ascending
Ascending
Descending
(0.39)
(0.55)
(0.50)
3.78
5.06
5.28
(0.39)
(0.46)
(0.59)
3.92
3.67
3.08
(0.83)
(0.47)
(0.56)
4.33
6.75
6.33
(0.75)
(1.02)
(0.96)
5.25
7.17
7.25
(0.91)
(1.02)
(0.92)
3.39
3.39
3.28
(0.69)
(0.65)
(0.61)
3.17
3.78
4.06
(0.69)
(0.60)
(0.67)
2.89
3.56
3.61
(0.73)
(0.69)
(0.67)
3.17
3.50
3.83
(0.59)
(0.67)
(0.91)
3.00
4.50
5.50
(0.77)
(0.61)
(0.93)
3.17
3.75
2.92
(0.82)
(0.76)
(0.62)
2.50
2.83
2.56
(0.27)
(0.24)
(0.24)
2.50
3.44
4.39
(0.23)
(0.37)
(0.50)
2.67
3.11
4.50
(0.31)
(0.57)
(0.64)
2.58
2.17
2.17
(0.35)
(0.23)
(0.24)
2.17
3.17
3.92
(0.22)
(0.54)
(0.79)
2.17
2.75
2.42
(0.31)
(0.59)
(0.41)
6.00
7.89
8.78
(2.10)
(3.74)
(3.40)
10.94
26.89
35.44
(3.20)
(5.29)
(6.28)
5.78
18.33
24.33
(1.63)
(3.65)
(4.75)
6.42
5.58
5.92
(3.13)
(2.62)
(2.64)
14.42
28.92
40.92
(3.88)
(4.54)
(5.10)
6.67
28.75
23.75
(2.35)
(6.67)
(6.02)
7.78
7.72
7.28
(3.43)
(3.39)
(3.08)
9.17
10.78
8.50
(3.20)
(3.99)
(2.44)
9.44
12.06
15.83
(4.02)
(4.62)
(5.51)
8.92
8.83
5.50
(4.47)
(3.67)
(2.00)
14.92
36.17
24.17
(5.11)
(9.39)
(5.25)
19.67
35.33
23.92
(8.55)
(10.04)
(5.65)
2.61
7.33
4.89
(0.48)
(3.76)
(2.42)
12.06
31.33
34.94
(3.27)
(6.76)
(6.71)
8.44
24.67
31.72
(3.11)
(5.34)
(7.14)
4.67
4.00
4.33
(1.87)
(1.59)
(1.80)
11.08
32.75
42.08
(3.54)
(6.60)
(7.47)
6.75
29.92
35.83
(2.43)
(7.24)
(7.12)
3.50
6.83
4.33
(1.19)
(3.64)
(1.79)
8.61
22.89
23.56
(2.77)
(5.17)
(5.42)
4.89
16.61
15.83
(1.72)
(4.17)
(4.67)
12.42
10.92
11.58
(5.40)
(5.44)
(5.25)
19.25
38.75
39.58
(5.23)
(8.05)
(5.81)
16.50
31.17
28.08
(5.41)
(7.60)
(6.76)
70.11
70.22
70.61
(1.37)
(1.14)
(1.20)
70.50
68.50
65.89
(1.07)
(0.81)
(1.16)
70.83
69.94
68.50
(0.95)
(1.13)
(1.06)
73.92
73.75
74.50
(3.28)
(3.15)
(3.23)
73.58
69.75
68.25
(3.36)
(3.00)
(2.86)
72.75
71.08
71.58
(3.67)
(3.33)
(3.08)
0.95
0.95
0.97
(0.01)
(0.01)
(0.01)
0.95
0.92
0.91
(0.01)
(0.01)
(0.01)
0.95
0.92
0.91
(0.01)
(0.01)
(0.02)
0.97
0.95
0.93
(0.01)
(0.01)
(0.01)
0.95
0.92
0.88
(0.01)
(0.02)
(0.02)
0.94
0.91
0.90
(0.01)
(0.02)
(0.01)
290.42
285.34
290.48
(8.15)
(9.42)
(9.67)
292.39
308.03
342.98
(9.66)
(13.07)
(25.81)
281.99
294.90
307.46
(8.17)
(10.49)
(14.38)
295.42
297.18
299.58
(21.70)
(13.82)
(17.77)
298.99
321.96
371.52
(17.82)
(11.23)
(43.29)
299.21
304.28
309.22
(18.38)
(11.08)
(19.58)
0.56
0.56
0.58
(0.01)
(0.01)
(0.01)
0.57
0.57
0.52
(0.01)
(0.02)
(0.02)
0.55
0.56
0.55
(0.01)
(0.01)
(0.01)
0.49
0.55
0.52
(0.05)
(0.02)
(0.04)
0.52
0.49
0.48
(0.04)
(0.04)
(0.05)
0.51
0.49
0.50
(0.05)
(0.04)
(0.05)
281.22
282.08
282.01
(1.97)
(1.78)
(1.90)
273.20
274.36
276.56
(1.80)
(1.59)
(1.90)
269.13
278.56
282.53
(1.66)
(2.01)
(2.38)
279.20
277.10
277.15
(3.14)
(2.84)
(2.84)
278.80
301.15
279.29
(3.22)
(4.43)
(3.36)
268.72
296.90
290.51
(2.93)
(4.04)
(4.40)
308.35
309.64
311.27
(2.82)
(3.25)
(3.31)
300.11
310.65
318.03
(2.71)
(2.64)
(3.21)
299.87
313.11
315.24
(2.26)
(3.28)
(3.82)
311.91
312.61
319.62
(4.41)
(3.56)
(4.74)
318.45
344.76
335.47
(4.59)
(6.24)
(4.08)
316.69
335.63
334.28
(4.26)
(6.33)
(6.02)
Cardiovascular
Heart Rate
0.00 g/kg
66.89
0.45 g/kg
73.72
0.65 g/kg
71.67
(1.93)
(3.13)
(2.78)
75.39
74.89
74.50
(2.78)
(2.77)
(2.73)
69.00
75.61
79.44
(3.33)
(3.01)
(3.42)
64.92
64.27
68.92
(3.18)
(3.38)
(3.73)
71.55
66.82
70.67
(3.84)
(3.16)
(3.71)
65.64
68.36
72.25
(3.50)
(3.95)
(4.37)
Cued RT
Go Cue
0.00 g/kg
0.45 g/kg
0.65 g/kg
No Go Cue
0.00 g/kg
0.45 g/kg
0.65 g/kg
10
Baseline
3.89
4.33
4.00
RIP
RT Correct
0.00 g/kg
0.45 g/kg
0.65 g/kg
Prop. Cor.
0.00 g/kg
0.45 g/kg
0.65 g/kg
20
Descending
(0.38)
(0.36)
(0.28)
DSST
Total Trial
0.00 g/kg
0.45 g/kg
0.65 g/kg
Prop. Cor.
0.00 g/kg
0.45 g/kg
0.65 g/kg
ASSS Sedation
Ascending
High Sensation Seekers
3.22
3.39
3.11
VAS
Stimulated
0.00 g/kg
0.45 g/kg
0.65 g/kg
Sedated
0.00 g/kg
0.45 g/kg
0.65 g/kg
Feel Drug
0.00 g/kg
0.45 g/kg
0.65 g/kg
Like Drug
0.00 g/kg
0.45 g/kg
0.65 g/kg
Figure 1: Effects of alcohol on visual-analog scale ratings of Light-Headed as a
function of time (Baseline, Ascending, Descending) following dose
administration for low (left panel) and high (right panel) sensation seekers.
Error bars represent + 1 SEM.
Results
Blood Alcohol Levels (BAL’s, Table 2)
Dose-related increases in BAL’s were observed during both ascending and descending
level sessions for low and high sensation seekers. No significant differences in BAL’s were
observed between low and high sensation-seeking groups, although means during
ascending level were significantly higher than during descending level for the 0.45 g/kg
dose.
Significant Alcohol and Alcohol x Time Interactions (Table 3)
ARCI: Alcohol increased ratings on the PCAG, LSD and A scales, although effects on the A
scale occurred only during ascending BAL’s.
VAS: Alcohol increased ratings on the Stimulated, Sedated, Light-Headed, Sick-to-Stomach,
High, Feel Drug and Like Drug scales.
ASSS: Alcohol increased ratings on the Stimulated and Sedated composite scales, with
magnitude of effect varying as a function of ascending and descending levels.
DSST: Alcohol decreased total trial rate and performance accuracy.
RIP: Alcohol increased reaction time (i.e., decreased trial rate) and decreased accuracy,
although effects on accuracy were limited to ascending levels.
Cued RT : Alcohol increased reaction time (i.e., decreased trial rate) and decreased
accuracy.
Cardiovascular: Alcohol increased heart rate, although effects were limited to descending
levels.
High Sensation Seekers
LowSensation Seekers
25
Table 3
Score
Previous studies indicate that high sensation seekers are at increased vulnerability to
drug abuse in part as a result of enhanced sensitivity to the reinforcing and other
behavioral effects of drugs. This ongoing study examines the effects of alcohol in
groups of high and low impulsive sensation-seeking adults matched on levels of
alcohol and drug use. Fifteen of twenty healthy volunteers scoring in the top and
bottom quartiles of gender-adjusted population norms on the impulsive-sensation
seeking scale of the Zuckerman-Kuhlman Personality Questionnaire (6 high- and 9 lowimpulsive sensation seekers) completed 7 test days in which assessments were
completed before (i.e., baseline) and after oral dose administration at times chosen to
equate blood alcohol levels on the ascending and descending portions of the bloodalcohol curve. Placebo was administered on the first test day, during which data are
collected but not analyzed. Each of three doses (0, 0.45 and 0.65 g/kg) was then tested
under double-blind conditions on 2 days according to a randomized-block design.
Alcohol impaired performance on psychomotor, impulsivity and attention tasks,
increased heart rate, and engendered both stimulant- and sedative-like verbal reports
of drug effect. Importantly, the magnitude of alcohol effects varied as a function of
ascending and descending blood alcohol levels. High sensation seekers reported
significantly greater reports of sedation on the Alcohol Sedation-Stimulation Scale and
Light-Headed on the Visual-Analog Scale during both ascending and descending blood
alcohol levels, suggesting that high sensation seekers are more sensitive to the acute
behavioral effects of alcohol than low sensation seekers. Supported by DA-05312 and
RR-15592.
Subjects: Fifteen healthy adults, ages 21 to 30, completed medical screening and gave
written consent prior to participating in outpatient studies lasting 4.5 hours per day (or until
BAL was <= 0.02 g/dl) for seven days. Six were classified as High Sensation Seekers, and
nine were classified as Low Sensation Seekers. All subjects received task training and
practice prior to the study until stable performance was observed.
Sensation-Seeking Status: All subjects completed items from the impulsive sensationseeking scale of the Zuckerman-Kuhlman Personality Questionnaire. Those who scored in
the upper and lower 25% of the population, based on established norms, were classified as
High and Low Sensation Seekers, respectively.
Drug: Each dose of alcohol (0, 0.45, 0.65 g/kg) was administered on two separate days
according to a randomized block design. An additional placebo dose was administered on
the first study days during which data were collected but not analyzed. Doses were
administered under double-blind conditions.
Procedure (Table 1): Daily schedules were constant throughout the study. Subjects
completed 30-minute sessions before drug administration, 30 minutes following drug
administration, and 75 and 90 minutes following drug administration of the 0.045 and 0.065
doses, respectively. Each session consisted of verbal report of drug effects (ARCI, VAS,
ASSS), psychomotor (digit-symbol substitution), impulsivity (Cued RT), and attention (rapid
information processing) measures.
Data Analysis: A mixed-model ANOVA was conducted with one between- (High vs. Low
Sensation Seeking Status) and two within-group (dose x 3 and time x 3) factors.
VAS Light-Headed
Descending
Figure 2: Effects of alcohol on the ASSS composite Sedated scale as a function of
time (Baseline, Ascending, Descending) following dose administration for low (left
panel) and high (right panel) sensation seekers. Error bars represent + 1 SEM.
Conclusions
1. The effects of alcohol on subject report measures of drug effect were consistent with the results of previous studies. Typical
stimulant- and sedative-like effects were observed on ARCI, VAS and ASSS scales. Dose-related increases were observed on several
scales that have been associated with the reinforcing effects of drugs (i.e., VAS Like Drug; ARCI PCAG and A scales; ASSS Stimulated
and Sedated scales).
2. High sensation-seekers exhibited greater sensitivity to the effects of alcohol on VAS ratings of Light-Headed and the ASSS
composite Sedated scale. Group differences in drug effects were observed on other scales, as well, but effects did not reach
statistical significance. To the extent that these measures are associated with the reinforcing effects of alcohol, the data suggest that
the reinforcing effects of alcohol may be greater in high sensation seekers than in low sensation seekers.
3. The effects of alcohol on measures of task performance were also consistent with the results of previous studies. Typical sedativelike effects were observed on DSST, RIP and Cued RT task performance. Differences in impairment as a function of ascending and
descending alcohol levels varied across tasks.
4. The effects of alcohol on several subject report, cardiovascular and task performance measures varied as a function of ascending
and descending alcohol levels, suggesting that the functional effects of alcohol vary as a function of relative changes in BAL.
5. High sensation seekers are more likely than low sensation seekers to engage in a variety of high-risk behaviors, including drug
use. These data suggest that while high sensation-seekers may be more likely to initiate experimentation with drug use, they may
also be more vulnerable to the reinforcing effects of alcohol, and thereby be at greater risk for developing repeated patterns of drugseeking behavior.