Table 2.

Bayesian learning model parameters^a

Model parameter	Baseline			tDCS − Baseline
	Anodal	Cathodal	Sham	Anodal	Cathodal	Sham
β	0.0846 ± 0.0318	0.0707 ± 0.0358	0.0808 ± 0.0403	−0.0031 ± 0.0332	0.0115 ± 0.0267	0.0107 ± 0.0480
ϕ	0.0304 ± 0.0349	0.0133 ± 0.0162	0.0700 ± 0.0770	−0.0285 ± 0.0313	−0.0018 ± 0.0114	−0.0638 ± 0.0699
λ̂	0.9489	0.9537	0.9406	−0.0073	−0.0083	−0.0127
θ̂	31.189	19.279	12.326	−2.3406	1.9519	11.465
σ̂d	0.0010	0.0028	0.0010	0.0025	−0.0001	0.0053

^aThe first three columns show the parameter estimates across all participants and trials within each stimulation group (anodal, cathodal, or sham) in the baseline condition. Columns 4 to 6 show the change in the parameter estimates under tDCS relative to baseline for each stimulation condition. Parameters β and ϕ were allowed to vary individually across participants and were fit in a hierarchical manner (see Materials and Methods). For these parameters, the table reports the means (± standard deviations) of the median values of each subject's posterior distribution. The remaining parameters were fit across the population; for these parameters, the table reports the medians of the population posterior distribution.