Brain maps of Iowa gambling task

From Brede Wiki
Jump to: navigation, search
Paper (help)
Brain maps of Iowa gambling task
Authors: Ching-Hung Lin, Yao-Chu Chiu, Chou-Ming Cheng, Jen-Chuen Hsieh
Citation: BMC Neuroscience 9 : 72. 2008 July
Database(s): CiteULike PubMed (PMID/18655719)
DOI: 10.1186/1471-2202-9-72.
Link(s): http://www.biomedcentral.com/content/pdf/1471-2202-9-72.pdf
Search
Web: Bing Google Yahoo!Google PDF
Article: BASE Google Scholar PubMed
Restricted: DTU Digital Library
Other: NIF
Services
Format: BibTeX Template from PMID
Extract: Talairach coordinates from linked PDF: CSV-formated wiki-formated

Brain maps of Iowa gambling task reports an functional magnetic resonance imaging study with subjects scanned during anticipation and outcome of the Iowa gambling task.

Table 1 of the paper contains an overview of the spatial location of activations published in previous Iowa gambling task neuroimaging papers.

Contents

[edit] Abstract from the Open Access paper

[edit] Background

Somatic Marker Hypothesis (SMH), based on clinical observations, delineates neuronal networks for interpreting consciousness generation and decision-making. The Iowa gambling task (IGT) was designed to verify the SMH. However, more and more behavioral and brain imaging studies had reported incongruent results that pinpointed a need to re-evaluate the central representations of SMH. The current study used event-related fMRI (functional Magnetic Resonance Imaging) to examine neural correlates of anticipation vs. outcome, wins vs. losses, and differential decks' contingencies of IGT.

[edit] Results

Behavioral results showed a prominent effect of frequency in driving choices. The insula and basal ganglia were activated during the anticipation phase while the inferior parietal lobule was activated during the outcome phase. The activation of medial prefrontal cortex was especially targeted during the high punishment contingencies. The data suggest that under uncertainty the normal decision makers can become myopic.

[edit] Conclusion

The insula and basal ganglia might play a vital role in long-term guidance of decision-making. Inferior parietal lobule might participate in evaluating the consequence and medial prefrontal cortex may service the function of error monitoring.

[edit] Subjects

Subject group (help)
Students
Description: College and graduate school students
Subjects/♂/♀: 24 / 8 / 16
Age: 21.0 ±3.1 (19–32)
Nationality: Taiwanese
Approval: Institutional Ethics Commitee of Taipei Veterans General Hospital
Databases:

A group of 24 students with 8 males and 16 females were included in the study. The Taiwanese group had a mean age of 21.0 with a range from 19 to 32. The study on the human subjects was approved by the Institutional Ethics Commitee of Taipei Veterans General Hospital.

"Twenty-four college and graduate school students, 19 to 32 years old (Mean age = 21.0 years old; SD = 3.1; 8 males, 16 females) participated in this study. They had not played the IGT before. Written informed consent was obtained from each subject prior to the experiment. Prior to the experiment, each subject gave informed consent to the experimental protocol, which had been approved by the Institutional Ethics Committee of Taipei Veterans General Hospital. The experiment was conducted in accordance with the Declaration of Helsinki." [1]

[edit] Experiment

The paper describes the experimental paradigm the following way:

"Each subject was asked to play a computerized four-deck IGT game according to the original design [48]. Subjects were asked to turn a card from the 4-decks voluntarily. The inside of the card was either in black or red, which was unrelated to gain or loss. The subjects were instructed to maximize gains and minimize losses when playing the game. The IGT contained four decks. Decks A and B had potentially large immediate gains ($ 100) and losses ($ -50 to $ -1150) in each trial and a disadvantageous final-outcome ($ -250) from the average of ten trials. Decks C and D had small immediate gain ($ 50) and loss ($ -25 to $ -200) and an advantageous final-outcome ($ 250) (for detailed gain-loss structure and instructions for IGT, please refer to the references [48,100,101]). Subjects did not know the internal IGT structure of gain and loss. The game ended with a total of 100 trials. Different card-display arrangement (ABCD, BCDA ...etc.) for each subject was implemented to counterbalance the card position effect and possible confound of eye movement. Subjects were instructed to play the game using real monetary value (New Taiwan dollar, NT) and were rewarded with their final winnings (divided by 1000). For example, a subject with an account balance of NT 320,000 at the end of the game was rewarded with 320 NT dollars (~US$ 10). The time interval of 6 seconds preceding the button press was defined as anticipation period and the interval after was defined as experience period "

Furthermore:

"Subjects conducted a short practice version of IGT for familiarization (with different internal structure of gain and loss) before actual scanning and during the tri-pilot scanning inside the MRI-scanner. The fMRI inter-trial interval was set to be longer than 10 seconds to increase the sensitivity of event-related design [101]. Subjects were free to select the card without time constraint. To avoid the MRI-signal inhomogeneity and the inter-session confounds, the experiment was devoid of 9 interruptions as the original IGT game where the subjects were asked two questions after each 10 trials [8,102-104]. Subjects used a joystick with a press-button for card selection. All subjects completed the fMRI-experiment in less than 1 hour. The structural and anatomical images were acquired after a 15 minute break outside the scanner."

[edit] Scanning

MRI Scanning (help)
Mode: fMRI
Scanner: Bruker MedSpec S300 system MRI 3.0T
Type: T2*-weighted gradient-echo EPI

(TR=2000ms, TE=50ms, FA=90°)

Slices: (thickness=5mm , gap=1mm)
Size: FOV=230x230mm matrix=64x64x20
Laboratory: missing laboratory

For fMRI T2*-weighted gradient-echo EPI scans were acquired with a 3.0T Bruker MedSpec S300 system MRI.

MRI Scanning (help)
Mode: aMRI
Scanner: Bruker MedSpec S300 system MRI 3.0T
Type: T1-weighted MDEFT

(TR=88.1ms, TE=4.12ms, FA=?)

Slices: (thickness=1.5mm )
Size: FOV=230x230mm matrix=256x256x128
Laboratory: missing laboratory

For aMRI T1-weighted MDEFT scans were acquired with a 3.0T Bruker MedSpec S300 system MRI.


"Images were acquired using a 3.0 T Bruker MedSpec S300 system MRI (Kalsrube, Germany) with a quadrature head coil. The subjects' heads were immobilized with a vacuum-beam pad in the scanner. Functional data were acquired with a T2*-weighted gradient-echo EPI using BOLD contrast (TR/TE/θ = 2000 ms/50 ms/90°, slice thickness = 5 mm, interslice interval = 1 mm, Field of view (FOV) = 230 × 230 mm2, 64 × 64 × 20 matrix, whole brain coverage). The first five images (dummy images) of each session were discarded from the analysis to eliminate possible non-equilibrium effects of magnetization. The anatomical image was acquired using a high-resolution T1-weighted, 3D gradient-echo pulse sequence modified driven equilibrium Fourier transform (MDEFT); TR/TE/TI = 88.1 ms/4.12 ms/650 ms, slice thickness = 1.5 mm, 256 × 256 × 128 matrix, FOV = 230 × 230 mm2." [2]


[edit] Results

[edit] Anticipation phase

Table 2 with 8 coordinates [3].

Anatomy
BA
x
y
z
No. vox
t
z
Coordinate search
Plot
1 Right insula 40 6 2 148 7.42 Brede Database Brede Wiki NeuroSynth SumsDB Not available
2 Right lentiform nuclear 26 -2 -6 119 7.37 Brede Database Brede Wiki NeuroSynth SumsDB Not available
3 Right superior temporal gyrus 50 -46 10 76 6.77 Brede Database Brede Wiki NeuroSynth SumsDB Not available
4 Left posterior insula -46 -6 14 96 6.65 Brede Database Brede Wiki NeuroSynth SumsDB Not available
5 Left anterior insula -34 14 10 67 6.61 Brede Database Brede Wiki NeuroSynth SumsDB Not available
6 Left lentiform nuclear -16 12 0 202 6.32 Brede Database Brede Wiki NeuroSynth SumsDB Not available
7 Left inferior parietal lobule -54 -28 30 31 5.90 Brede Database Brede Wiki NeuroSynth SumsDB Not available
8 Left cingulate gyrus -4 18 30 32 5.51 Brede Database Brede Wiki NeuroSynth SumsDB Not available

[edit] Experience phase

Table 3 with 3 coordinates.

Anatomy
BA
x
y
z
No. vox
t
z
Coordinate search
Plot
1 Right inferior parietal lobule 36 -62 44 562 7.68 Brede Database Brede Wiki NeuroSynth SumsDB Not available
2 Right superior frontal gyrus 22 10 60 41 5.52 Brede Database Brede Wiki NeuroSynth SumsDB Not available
3 Left medial frontal gyrus -42 22 32 76 5.49 Brede Database Brede Wiki NeuroSynth SumsDB Not available
Personal tools