Genital-prioritized attentional bias in lifelong premature ejaculation: behavioral evidence from eye-tracking and machine learning
摘要
Lifelong premature ejaculation (LPE) involves altered responses to sexual cues. Neuroimaging has identified attention-related neural abnormalities in LPE, but behavioral evidence for attentional bias remains limited. Using eye tracking, we compared visual-attention patterns in 35 heterosexual men with LPE (andrology outpatient clinic, Henan Provincial People’s Hospital) and 38 heterosexual healthy controls (HCs) (online advertisements on official platforms of Henan Provincial People’s Hospital and Xidian University), from Nov 2023 to Jun 2024. Participants freely viewed three categories of sexual images (bikini-clad, nude, intercourse). Gaze metrics—first fixation order (FFO), fixation count (FC), and proportion of dwell time (PDT)—were extracted within predefined areas of interests (AOIs; face, chest, genital) for each stimulus category, yielding 27 candidate eye-tracking features per participant (3 categories × 3 AOIs × 3 metrics). We then applied sequential backward selection (SBS) with support vector machine (SVM) to select the most discriminative feature subset. An SVM classifier trained on the selected features distinguished LPE from HCs with 82.2% accuracy (AUC = 0.78). Compared with HCs, LPE showed earlier genital orienting (FFO: nude 4.2 ± 1.5 vs 6.0 ± 2.2, p < 0.001; intercourse 3.8 ± 1.5 vs 4.9 ± 1.9, p = 0.004) and more genital fixations (FC: bikini-clad 4.2 ± 1.6 vs 3.3 ± 1.2, p = 0.006; intercourse 7.9 ± 3.1 vs 6.1 ± 2.0, p = 0.008), indicating a genital-prioritized attentional bias. Anxiety and depression scores were higher in LPE (SAS: 34.1 ± 6.4 vs 29.4 ± 5.8, p = 0.003; SDS: 34.8 ± 7.6 vs 29.5 ± 6.8, p = 0.003), but no eye-tracking features correlated with these symptoms. Earlier genital orienting correlated with greater LPE severity (FFO vs PEDT: nude r = −0.47, p < 0.001; intercourse r = −0.36, p = 0.002). This study provides the first behavioral evidence of a genital-prioritized attentional bias in heterosexual men with LPE, offering novel mechanistic insight into its neurocognitive underpinnings.