Role of the striatum in incidental learning of sound categories

Behavioral performance. (A) Proportion correct categorization of offset- and onset-category exemplars in the posttest. Hashed bars indicate mean performance across the trained exemplars experienced in the videogame. Solid bars indicate mean performance for novel exemplars withheld from training (i.e., generalization) in the experimental (blue) and control (red) groups. (B) Group average in-scanner videogame performance, as measured by the highest game level achieved. (C) Correlation of the videogame performance (highest game level achieved) and categorization accuracy for the novel offset- and onset-category exemplars. Pearson’s correlation r values are shown. Dashed lines in A and C indicate chance level (0.25) performance. Error bars indicate ±1 SEM. See SI Appendix, Fig. S1 for further analysis of behavioral error pattern differences across the experimental and control groups.

Activation of the striatum across the experimental and control groups during videogame training. (A) Regions within the striatum exhibiting a significant Group × Time Course effect in response to game audiovisual stimulus events. The highlighted regions are a union of active striatal clusters across the three functional runs (caudate body and putamen; SI Appendix, Table S1). (B) The average activation time course of the striatal regions active in videogame play. Shaded regions indicate ±1 SEM. Post hoc tests revealed greater BOLD activation in the experimental than control group (t₂₅s > 2.23, Ps < 0.035 from 4.5 to 10.5 s from the start of each game trial).

Relationship between behavioral measures and striatal activation. (A) Correlation between the activation of striatal clusters during game play and generalization of category learning to novel onset-category exemplars in an explicit posttraining categorization test (Left), and in-scanner videogame performance (Right). Data points and regression lines of the experimental and control groups are indicated by blue and red, respectively. β-Coefficient estimates indicate the peak activation of the striatum during game play shown in Fig. 3B. (B) Summary of the relationships among behavioral game performance, posttraining categorization, and striatal activation during game play. Pearson’s correlation r values are derived from an individual, post hoc correlation analysis following the significant Group × Striatal Activation interaction effect from a multiple linear regression analysis predicting corresponding behavioral performance measure.