Table 1. Values of the model’s parameters across decision types and decision difficulties.

Values of the drift-rate parameter, I, for the congruent and incongruent options; for the leak rate, k; and for the noise scaling factor, c. We fixed the threshold at the value of 0.3. The values in the table are for the component of the model where the decisions were made. Hence, they are for Region X in deliberate decisions and for the SMA in arbitrary ones. Note that, for deliberate decisions, drift-rate values in the SMA were 1.45 times smaller than the values in this table for each entry.

Decision type	Decision difficulty	Icongruent	Iincongruent	K	C
Deliberate decisions (Region X values)	Easy	0.23	0.06	0.52	0.08
	Hard	0.18	0.09	0.53	0.11
Arbitrary decisions (SMA values)	Easy	0.24	0.21	0.53	0.22
	Hard	0.22	0.20	0.54	0.23