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afex (version 1.4-1)

stroop: Stroop data from Lin et al. (2020, Psych. Science)

Description

Lin, Saunders, Friese, Evans, and Inzlicht (2020) investigated ego depletion. An initial high-demand task was followed by a Stroop task. The data of the Stroop task from all 4 of their studies is included here.

Usage

stroop

Arguments

Format

A data frame with 246600 rows and 7 variables:

pno

participant id (preceded by study id), factor with 685 levels

condition

experimental condition (control/low demand, deplete/high demand), factor with 2 levels

study

study number (1, 2, 3, 4), factor with 4 levels

trialnum

trial number

congruency

Stroop congruency (congruent, incongruent), factor with 2 levels

acc

accuracy (0: error, 1: correct)

rt

reaction time (seconds)

Details

Their abstract: People feel tired or depleted after exerting mental effort. But even preregistered studies often fail to find effects of exerting effort on behavioral performance in the laboratory or elucidate the underlying psychology. We tested a new paradigm in four preregistered within-subjects studies (N = 686). An initial high-demand task reliably elicited very strong effort phenomenology compared with a low-demand task. Afterward, participants completed a Stroop task. We used drift-diffusion modeling to obtain the boundary (response caution) and drift-rate (information-processing speed) parameters. Bayesian analyses indicated that the high-demand manipulation reduced boundary but not drift rate. Increased effort sensations further predicted reduced boundary. However, our demand manipulation did not affect subsequent inhibition, as assessed with traditional Stroop behavioral measures and additional diffusion-model analyses for conflict tasks. Thus, effort exertion reduced response caution rather than inhibitory control, suggesting that after exerting effort, people disengage and become uninterested in exerting further effort.