Pupil dilation in the Simon task as a marker of conflict processing

Abstract

Cognitive demands in response conflict paradigms trigger negative affect and avoidance behavior. However, not all response conflict studies show increases in physiological indices of emotional arousal, such as pupil diameter. In contrast to earlier null-results, this study shows for the first time that small (about 0.02 mm) conflict-related pupil dilation can be observed in a Simon task when stimuli do not introduce a light reflex. Results show that response-conflict in Simon trials induces both pupil dilation and reaction-time costs. Moreover, sequential analyses reveal that pupil dilation mirrors the conflict-adaptation pattern observed in reaction time (RT). Although single-trial regression analyses indicated that pupil dilation is likely to reflect more than one process at the same time, in general our findings imply that pupil dilation can be used as an indirect marker of conflict processing.

Pupil dilation during recognition memory: Isolating unexpected recognition from judgment uncertainty

“…Here the effort expended for both correct rejections and hits is directly altered by whether or not the predictive recognition cues are valid or invalid, with the latter expected to heighten effort by slowing performance, increasing errors and generating conflict between expectations and memory signals (as well as reducing subjective confidence, see SI section 2). In other response conflict paradigms, such as the Stroop and Simon tasks, this type of heightened conflict produces greater pupil dilation, which has also been interpreted as 44 reflecting increased effort in line with the Cognitive Load model (Laeng et al, 2011;Steenbergen & Band, 2013). Despite the observed decrement in performance under invalid cueing for both 'old' and 'new' decisions, suggesting that conflict was indeed instantiated in both conditions, the typical analysis of the trial-averaged pupillary data only yielded a reliable dilation increase for invalid 'old' decisions, and not invalid 'new' decisions (see Figures 2 and 3).…”

“…Critically, under voluntary attention, increasingly effortful tasks should yield increasingly slowed, erroneous and uncertain responding (Kahneman, 1973). These behavioral indices of voluntary attention/effort overlap with those in response conflict paradigms which also yield increased pupil dilation for conditions of heightened conflict and associated uncertainty; for example, when naming colour-incongruent words in the Stroop task (Laeng, Ørbo, Holmlund, & Miozzo, 2011;Stroop, 1935) and when making left/right button-presses to spatially incompatible locations in the Simon task (Simon, 1969Steenbergen & Band, 2013.…”

“…This is because invalid cueing for both old and new materials has been shown to adversely affect judgment accuracy, speed and confidence, given that it sets up a conflict between recovered memorial signals and expectations (Jaeger et al, 2012;Jaeger, Konkel, & Dobbins, 2013;Konkel, Selmeczy, & Dobbins, 2015;O'Connor et al, 2010;Selmeczy & Dobbins, 2012). Increased dilation for both invalid cue types would converge with demonstrations of increased dilation during Stroop (Laeng et al, 2011) and Simon conflict manipulations (Steenbergen & Band, 2013), and in turn would support the idea that the previously reported pupil old/new effect indeed reflected the amount of volitional effort expended, which just happens to be larger on average for old versus new recognition conclusions in standard, uncued recognition paradigms.…”

How effortful is cognitive control? Insights from a novel method measuring single-trial evoked beta-adrenergic cardiac reactivity

“…An interpretation of these null effects suggests that available evidence from other physiological measures of effort such as pupil dilation (e.g. van Steenbergen & Band, 2013) and skin conductance response (e.g. Naccache et al, 2005) in cognitive control tasks, could simply reflect general arousal which does not necessarily involve effort mobilization.…”

“…Although cognitive control has often been characterized as a process requiring effort (Hasher & Zacks, 1979;Kahneman, 1973;Mulder, 1986;Schneider & Shiffrin, 1977;Westbrook & Braver, 2015; see also Rothbart, Ellis, Rueda, & Posner, 2003) there is little empirical evidence to support this notion. Only a few studies have established a link between cognitive control and effort based on demonstrating an increase in pupil dilation in response to conflict trials in cognitive control paradigms (Brown et al, 1999;Laeng, Ørbo, Holmlund, & Miozzo, 2011;Rondeel, van Steenbergen, Holland, & van Knippenberg, 2015;Siegle, Ichikawa, & Steinhauer, 2008;Siegle, Steinhauer, & Thase, 2004;van Bochove, van der Haegen, Notebaert, & Verguts, 2013;van Steenbergen & Band, 2013;van Steenbergen, Band, & Hommel, 2015;Wendt, Kiesel, Geringswald, Purmann, & Fischer, 2014). However, although increased pupil dilation has been argued to reflect increased effort (Kahneman, 1973), it might simply reflect an increase in physiological arousal non-specific to effort mobilization (Bradley, Miccoli, Escrig, & Lang, 2008).…”