title: Transcranial Direct Current Stimulation Does Not Influence the Speed-Accuracy Tradeoff in Perceptual Decision-making: Evidence from Three Independent Studies.
abstract: In perceptual decision-making tasks, people balance the speed and accuracy with which they make their decisions by modulating a response threshold. Neuroimaging studies suggest that this speed-accuracy tradeoff is implemented in a corticobasal ganglia network that includes an important contribution from the pre-SMA. To test this hypothesis, we used anodal transcranial direct current stimulation (tDCS) to modulate neural activity in pre-SMA while participants performed a simple perceptual decision-making task. Participants viewed a pattern of moving dots and judged the direction of the global motion. In separate trials, they were cued to either respond quickly or accurately. We used the diffusion decision model to estimate the response threshold parameter, comparing conditions in which participants received sham or anodal tDCS. In three independent experiments, we failed to observe an influence of tDCS on the response threshold. Additional, exploratory analyses showed no influence of tDCS on the duration of nondecision processes or on the efficiency of information processing. Taken together, these findings provide a cautionary note, either concerning the causal role of pre-SMA in decision-making or on the utility of tDCS for modifying response caution in decision-making tasks.
authors.affiliation: University of Amsterdam.
authors.forename: Gilles
authors.initials: G
authors.lastname: de Hollander
authors.affiliation: University of California, Berkeley.
authors.forename: Ludovica
authors.initials: L
authors.lastname: Labruna
authors.affiliation: Universiteit Leiden.
authors.forename: Roberta
authors.initials: R
authors.lastname: Sellaro
authors.affiliation: University of Amsterdam.
authors.forename: Anne
authors.initials: A
authors.lastname: Trutti
authors.affiliation: Universiteit Leiden.
authors.forename: Lorenza S
authors.initials: LS
authors.lastname: Colzato
authors.affiliation: The Ohio State University.
authors.forename: Roger
authors.initials: R
authors.lastname: Ratcliff
authors.affiliation: University of California, Berkeley.
authors.forename: Richard B
authors.initials: RB
authors.lastname: Ivry
authors.affiliation: University of Amsterdam.
authors.forename: Birte U
authors.initials: BU
authors.lastname: Forstmann
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D016000:Cluster Analysis; D003463:Cues; D003657:Decision Making / Q000502:physiology*; D004192:Discrimination, Psychological / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D009039:Motion Perception / Q000502:physiology*; D009044:Motor Cortex / Q000502:physiology*; D009483:Neuropsychological Tests; D011930:Reaction Time / Q000502:physiology*; D015203:Reproducibility of Results; D065908:Transcranial Direct Current Stimulation; D055815:Young Adult