Fig. 4: Robot-induced presence hallucination and its link to human numerosity estimation (study 1). | Nature Communications

Fig. 4: Robot-induced presence hallucination and its link to human numerosity estimation (study 1).

From: Numerosity estimation of virtual humans as a digital-robotic marker for hallucinations in Parkinson’s disease

Fig. 4

a Robot-induced presence hallucinations assessment ratings (asynchronous versus synchronous sensorimotor stimulation). Participants reported higher presence hallucinations ratings in the asynchronous sensorimotor condition (mean = 2.29, SD = 1.96) compared to the synchronous sensorimotor condition (mean = 1.50, SD = 1.99) (χ² (1, N = 28) = 12.00, p = 0.0005; effect size = −0.61 (95% confidence interval = [−1.01; −0.20])). Each linked pair of dots indicates the individual mean rating of robot-induced presence hallucination (asynchronous (dark grey) and synchronous (light grey) sensorimotor stimulation). The dots with the bar on the left and right sides indicate the mixed-effects linear regression between asynchronous (dark grey) and synchronous (light gray) sensorimotor stimulation. Error bar represents 95% confidence interval. b Results of causal mediation analysis. The effect of robotic sensorimotor stimulation (synchronous or asynchronous) on human numerosity estimation was partially mediated via robot-induced presence hallucination question rating. The regression coefficient between robotic sensorimotor stimulation (synchronous or asynchronous) and human numerosity estimation was significant ((F(1,27) = 26.05; p = 2.3e−5)). The regression coefficient between robot-induced presence hallucination question rating and human numerosity estimation was significant (F(1,27) = 10.44; p = 0.003). The indirect effect of robotic sensorimotor stimulation (synchronous or asynchronous) on human numerosity estimation via robot-induced presence hallucination question rating was 0.04. The significance of the indirect effect was tested using bootstrapping procedures (1000 samples), and the 95% confidence interval was computed by determining the indirect effects at the 2.5th and 97.5th percentiles. The indirect effect was significant (p = 0.01; 95% confidence interval = [0.006; 0.08]). *P ≤ 0.05; **P ≤ 0.01; ***P ≤ 0.001. n = 28 healthy participants. Source data are provided as a Source Data file.

Back to article page