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Volume 64, Issue 3, Pages 431-439 (November 2009)
An Automatic Valuation System in the Human Brain: Evidence from Functional Neuroimaging Maël Lebreton, Soledad Jorge, Vincent Michel, Bertrand Thirion, Mathias Pessiglione Neuron Volume 64, Issue 3, Pages (November 2009) DOI: /j.neuron Copyright © 2009 Elsevier Inc. Terms and Conditions
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Figure 1 Tasks Overview Age rating (A) and pleasantness rating (B) tasks were performed during scanning, whereas choice task (C) was conducted after scanning. Successive screenshots displayed during a given trial are illustrated from left to right, with durations in milliseconds. In the rating tasks, subjects had to move a cursor on an analog scale to indicate the age or the pleasantness of a picture, which could be a face, house, or painting. In the choice task, subjects had to state which picture they preferred between two of those in the same category (face, house, or painting). Neuron , DOI: ( /j.neuron ) Copyright © 2009 Elsevier Inc. Terms and Conditions
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Figure 2 Behavioral Results
(A) Correlation between age and pleasantness ratings. The dots correspond to the 360 pictures. Ratings were averaged across the 20 subjects. The black line indicates linear regression fit. (B) Distribution of agreement rates over the 180 hard and 180 easy comparisons. Plots show the number of stimuli pairs for which a specific percentage of subjects expressed the same preference. (C) Prediction scores (percentage of pairs for which the preferred picture got the higher pleasantness rating), averaged separately for easy and hard comparisons, and for both the immediate and delayed choice task sessions. (D) Difference in pleasantness ratings (δV) between preferred and nonpreferred pictures (P − NP), averaged separately for easy and hard comparisons, in both the immediate and delayed choice task sessions. (E) Correlation between response times and z-scored δV in immediate (left) and delayed (right) choice tasks. The dots represent 18 comparisons, ranked according to δV and averaged across subjects. Error bars represent intersubject SEM. (∗), significant difference between conditions in black (p < 0.01, two-tailed paired t test) or from chance in white (p < 0.001, one-tailed paired t test). Neuron , DOI: ( /j.neuron ) Copyright © 2009 Elsevier Inc. Terms and Conditions
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Figure 3 Statistical Parametric Maps of Stimulus Category
Each category (face, house, painting) was contrasted with the two others at the individual level. Slices were taken at maxima of interest indicated by red pointers on glass brains. Areas shown in gray/black on glass brains and in red/yellow on coronal slices showed significant group level random effect (one-sample t test, p < 0.001, uncorrected). [x y z] coordinates of the maxima refer to the Montreal Neurological Institute space. Color scales on the right indicate t values. Neuron , DOI: ( /j.neuron ) Copyright © 2009 Elsevier Inc. Terms and Conditions
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Figure 4 Statistical Parametric Maps of Values and Preferences
(Top) Correlation with pleasantness ratings. (Bottom) conjunction between pleasantness rating (above contrast) and preference contrast (preferred minus nonpreferred pictures). The bottom map was used to identify regions comprising the brain valuation system (BVS). Slices were taken at maxima of interest indicated by red pointers on glass brains. Areas shown in gray/black on glass brains and in red/yellow on coronal slices showed significant group level random effect (one-sample t test, p < 0.001, uncorrected). [x y z] coordinates of the maxima refer to the Montreal Neurological Institute space. Color scales on the right indicate t values. Neuron , DOI: ( /j.neuron ) Copyright © 2009 Elsevier Inc. Terms and Conditions
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Figure 5 Value Encoding in the Brain Valuation System
Regression coefficients (betas) were extracted in the different brain valuation regions, located at the intersection of blue lines on the sagittal slices. These coefficients were plotted against z-scored values expressed as pleasantness ratings. The dots represent 18 pictures, ranked in order of ascending values and averaged across subjects. Error bars represent between-subject SEM. Neuron , DOI: ( /j.neuron ) Copyright © 2009 Elsevier Inc. Terms and Conditions
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Figure 6 Preference Encoding in the Brain Valuation System
Regression coefficients (betas) were contrasted between preferred and nonpreferred pictures (P − NP) in the different brain valuation regions, separately for the different experimental conditions. (A) Comparison between brain regions. VMPFC, ventromedial prefrontal cortex; VS, ventral striatum; H, hippocampus; PCC, posterior cingulate cortex. (B) Comparison between choice tasks (easy and hard comparisons in both immediate and delayed sessions). (C) Comparisons between shared and personal preferences, separated by median agreement rate. (D) Comparison between stimulus categories (face, house, and painting). (E) Comparison between rating tasks (pleasantness/explicit and age/distractive). Bars represent mean ± intersubject SEM. (∗), significant difference between conditions in black (p < 0.05, two-tailed paired t test) or from chance in white (p < 0.05, one-tailed paired t test). Neuron , DOI: ( /j.neuron ) Copyright © 2009 Elsevier Inc. Terms and Conditions
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