Fig. 1.

Individual data plots for identification accuracy and affective valuation for each laughter condition, across participant groups. The panels represent experimental laughter conditions (mirthful, hostile, posed) and the spectrally inverted laughter (inverted) control condition. Plotted on each panel are individuals' raw laughter identification accuracy scores (indexed as the unbiased hit rate) or affective valence ratings (on a 5-point Likert scale: 1, very unpleasant; 5, very pleasant) within each participant group. AD, patient group with typical Alzheimer's disease; BV, patient group with behavioural variant frontotemporal dementia; HC, healthy control group; NFV, patient group with nonfluent-agrammatic variant primary progressive aphasia; SV, patient group with semantic variant primary progressive aphasia.