The role of the right parietal lobe in the perception of causality: a tDCS study

Abstract

Inferring causality is a fundamental feature of human cognition that allows us to predict outcomes in everyday events. Here, we use direct current stimulation (tDCS) to investigate the role of the right parietal lobe in the perception of causal events. Based on the results of a previous fMRI investigation, we hypothesized that the right parietal lobe plays a specific role in the processing of spatial attributes that contribute to judgments of causality. In line with our hypothesis, we found polarization-dependent modulation of causal judgments and corresponding reaction times (RTs) for trials with increasing violation of spatial contiguity in launching events. This effect was further modulated by temporal violations, as the effect of tDCS on the use of spatial information for causality judgements was strongest for trials with high temporal violations. Thus, especially for ambiguous trials with regard to temporal patterns, cathodal stimulation led to more liberal causality judgments for trials with high angles in movement trajectory. Furthermore, we found faster RTs after anodal stimulation of the right parietal lobe. These findings suggest a reduced influence of spatial attributes on the perception of causality after cathode stimulation of the right parietal lobe and an increased processing efficiency after anodal stimuli of the same region. These data demonstrate polarization-dependent tDCS modulation of spatial processing mechanisms within the right parietal lobe that contribute to the perception of causality.

Neural correlates of causality judgment in physical and social context—The reversed effects of space and time

“…Guski and Troje, 2003;Schlottmann, 2000;Schlottmann and Shanks, 1992;Schlottmann et al, 2006;Young and Sutherland, 2009). Greater angle deviations in the movement path also lead to decreasing impressions of causality (Straube and Chatterjee, 2010;Straube et al, 2011). As shown in Fig.…”

“…Many variations of this kind of experiment have been used to investigate the key parameters that lead to the perception of causality. Those key parameters include a gap between both objects (Oakes and Kannass, 1999;Saxe and Carey, 2006;Schlottmann and Anderson, 1993;Yela, 1952), time delays before the second object starts to move (Guski and Troje, 2003;Schlottmann and Shanks, 1992;Schlottmann et al, 2006;Young and Sutherland, 2009), and the trajectory of movement (Straube and Chatterjee, 2010;Straube et al, 2011) These studies generally suggest that spatial and temporal manipulations play an important role in this context.…”

“…Schlottmann et al, 2006) we expected opposite effects of our stimulus manipulations on physical and social causality: Small deviations in the stimulus (small angle and short time delay) lead to causal judgment in the physical task, and non-causal judgment in the social task, whereas large deviations (great angle and long time delay) lead to the opposite judgments. In the fMRI analyses, we expect to find different brain activations during physical and social tasks in brain regions predominantly related to perceptual (e.g., for physical task and spatial effects in the parietal lobe, and temporal effects in the supplementary motor area (SMA) and the basal ganglia (Straube and Chatterjee, 2010;Straube et al, 2011)) and inferential (e.g., for social tasks in the prefrontal cortex (Tavares et al, 2008)) processing mechanisms. The medial prefrontal cortex (MPFC) has previously been described as instantiating several psychological mechanisms (e.g.…”

“…We compared brain activations of physical and social contexts as well as activations concerning causality judgments. Both contexts used highly comparable stimuli, each including a blue and a red simple object (circle) (see Straube and Chatterjee, 2010;Straube et al, 2011). In the physical context the blue ball collided with the red ball, whereas in the social context the blue ball passed the red ball.…”

Neural correlates of continuous causal word generation

“…Here, especially the spatial and temporal characteristics of the stimulus event play an important role in the perception of physical causality Michotte, 1963;Straube and Chatterjee, 2010;Straube et al, 2011). Imaging evidence moreover points to a distinction between perceptual and inferential causalities , the latter seeming to activate medial (Fonlupt, 2003) and lateral frontal brain regions .…”