We also compared a whole-brain decoder with a GLM-restricted deco

We also compared a whole-brain decoder with a GLM-restricted decoder (MVA-G). Furthermore, we studied if decoding is based on average time-series across clusters (MVA-T), or driven by multivariate activity patterns within individual clusters (MVA-C). We used a one-way anova to test for differences in decoding performance Trametinib mw among the four decoders. Decoding performance varied significantly (Fig. 3) across the four different decoders, F3,24 = 9.04, P = 0.000346. A Tukey test indicates that MVA-W (M = 77.6, SD = 11.6) was decoded significantly better than MVA-C (M = 56.1, SD = 3.74), P = 0.001. Similarly, MVA-G (M = 79, SD = 9.75) was

decoded significantly better than MVA-C (M = 56.1, SD = 3.74), P = 0.001. No

statistically significant difference was found between MVA-W, MVA-G and MVA-T (M = 68.6, SD = 9.97), though a trend towards significance could be observed. No statistically significant difference was found between MVA-C and MVA-T. Taken together, these results suggest that whole-brain multivariate decoding and GLM-restricted decoding perform comparably. Furthermore, because MVA-W and MVA-G both performed significantly higher than MVA-C, it indicates that decoding depends on distributed patterns of cortical activity. Finally, lower decoding performance for MVA-T compared with MVA-W and MVA-G suggests that multivariate patterns of activity distributed across clusters drive decoding

performance. To further examine online decoding results using MVA-W, we tested how its selleck screening library decoding performance evolved during the trials. The results of a TR-by-TR analysis in the non-feedback condition (Fig. 4A) showed that decoding accuracy followed BOLD activity, increasing in the initial 6 s and leveling off afterwards. Moreover, attend-face trials were decoded with an accuracy of 84% (SD = 14.3), whereas attend-place trials were decoded with an accuracy of 71% (SD = 15.3), Flavopiridol (Alvocidib) respectively. A paired-samples t-test failed to reveal a statistically significant (t6 = 1.8117, P = 0.12) difference between attend-face and attend-place trials (Fig. 4B). However, a statistically significant asymmetry was found for the familiarity of face and place stimuli in the post hoc behavioral test. A paired-samples t-test showed that subjects ranked faces (M = 3.805, SD = 0.015) more familiar than places (M = 2.85, SD = 0.016), t10668 = 43.19, P = 0. Additionally, we tested how BOLD signal varied for attend-face and attend-place trials in voxels used by the decoder (Fig. 4D and E). A two-tailed paired-samples t-test on percent signal change showed that face-selective voxels responded more strongly to attend-face trials (M = 0.319, SD = 0.123) than to attend-place trials (M = 0.179, SD = 0.142), t6 = 2.468, P = 0.048.

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