Table 1

The immediate net value of each trial and gain-loss structure in the original IGT and SGT
IGT Serial Numbers
 A
 B
 C
 D
 SGT
 A
 B
 C
 D
1
 100
 100
 50
 50
 1
 200
 100
 -200
 -100
2
 100
 100
 50
 50
 2
 200
 100
 -200
 -100
3
 -50
 100
 0
 50
 3
 200
 100
 -200
 -100
4
 100
 100
 50
 50
 4
 200
 100
 -200
 -100
5
 -200
 100
 0
 50
 5
 -1050
 -650
 1050
 650
6
 100
 100
 50
 50
 6
 200
 100
 -200
 -100
7
 -100
 100
 0
 50
 7
 200
 100
 -200
 -100
8
 100
 100
 50
 50
 8
 200
 100
 -200
 -100
9
 -150
 -1150
 0
 50
 9
 200
 100
 -200
 -100
10
 -250
 100
 0
 -200
 10
 -1050
 -650
 1050
 650
11
 100
 100
 50
 50
 11
 200
 100
 -200
 -100
12
 -250
 100
 25
 50
 12
 200
 100
 -200
 -100
13
 100
 100
 -25
 50
 13
 200
 100
 -200
 -100
14
 -150
 -1150
 50
 50
 14
 200
 100
 -200
 -100
15
 -100
 100
 50
 50
 15
 -1050
 -650
 1050
 650
16
 100
 100
 50
 50
 16
 200
 100
 -200
 -100
17
 -200
 100
 25
 50
 17
 200
 100
 -200
 -100
18
 -50
 100
 -25
 50
 18
 200
 100
 -200
 -100
19
 100
 100
 50
 50
 19
 200
 100
 -200
 -100
20
 100
 100
 0
 -200
 20
 -1050
 -650
 1050
 650
21
 100
 -1150
 50
 50
 21
 200
 100
 -200
 -100
22
 -200
 100
 50
 50
 22
 200
 100
 -200
 -100
23
 100
 100
 50
 50
 23
 200
 100
 -200
 -100
24
 -250
 100
 0
 50
 24
 200
 100
 -200
 -100
25
 100
 100
 25
 50
 25
 -1050
 -650
 1050
 650
26
 -100
 100
 0
 50
 26
 200
 100
 -200
 -100
27
 -150
 100
 50
 50
 27
 200
 100
 -200
 -100
28
 -50
 100
 50
 50
 28
 200
 100
 -200
 -100
29
 100
 100
 -25
 -200
 29
 200
 100
 -200
 -100
30
 100
 100
 0
 50
 30
 -1050
 -650
 1050
 650
31
 -250
 100
 50
 50
 31
 200
 100
 -200
 -100
32
 -100
 -1150
 50
 50
 32
 200
 100
 -200
 -100
33
 -150
 100
 50
 50
 33
 200
 100
 -200
 -100
34
 100
 100
 25
 50
 34
 200
 100
 -200
 -100
35
 100
 100
 25
 -200
 35
 -1050
 -650
 1050
 650
36
 100
 100
 50
 50
 36
 200
 100
 -200
 -100
37
 -50
 100
 -25
 50
 37
 200
 100
 -200
 -100
38
 -200
 100
 50
 50
 38
 200
 100
 -200
 -100
39
 100
 100
 0
 50
 39
 200
 100
 -200
 -100
40
 100
 100
 -25
 50
 40
 -1050
 -650
 1050
 650
Final Outcomes
 -1000 ($)
 -1000 ($)
 +1000 ($)
 +1000 ($)
 Final Outcomes
 -2000 ($)
 -2000 ($)
 +2000 ($)
 +2000 ($)

Note. In these gambling tasks, the internal gamble structure of IGT and SGT and the trial to end the game is unknown to the subjects. The subjects are asked to minimize monetary expenditure and maximize their winnings by choosing one card from the four decks in each trial. In the table, negative values are marked with a bold font size. (Left part: IGT) Deck A contains the relative high-frequency loss, while decks B, C, and D contain the high-frequency gain (net value within each trial). Decks A and B have negative net value (namely, the EV), -250($) over an average of ten trials; moreover, C and D have a positive net value of +250($) over an average of ten trials. (Right part: SGT) Five cumulative trials are repeated for each deck in the Soochow Gambling Task, decks A and B have high-frequency gain, while decks C and D exhibit a reversed gain-loss pattern. The task enlarges the difference between positive and negative EVs to make the difference more noticeable than in the Iowa Gambling Task. While playing this game, subjects only experienced a gain or a loss during each trial, and there was no reciprocal gain-loss within individual trials.

Chiu et al. Behavioral and Brain Functions 2008 4:13   doi:10.1186/1744-9081-4-13