2.9.4 Exploratory Statistical Cluster Plot (SCP) Analysis
To provide a more complete picture of the dataset, a secondary analysis was conducted across all 64 channels at all timepoints in the epoch (-350 ms before response-onset onset to 300 ms after the button press response). The x-axis of the SCP represents time post-response onset in milliseconds, and the y-axis represents individual electrodes spatially clustered at the scalp regional level. ERP waveforms were compared between ASD and TD groups using a running two-tailed independent samples t-test with a significance threshold set to p < 0.05. Data were additionally compared across four levels of RT stratification (fastest 25% of trials, middle 25-50%, middle 50-75%, slowest 25%) using 1-way ANOVAs with the significance threshold set to 0.05. To examine age-related effects between ASD and TD participants, two-tailed independent sample t-tests were performed for each timepoint separately using the same significance threshold. We are aware that conclusions based on SCPs could potentially result in a high rate of false-positive errors due to the large volume of tests performed. To account for this issue, we have implemented temporal corrections. Only timepoints for which the 0.05 p-value criterion for at least 7 consecutive data points (13.6 ms) were considered significant.
Results