Auditory cueing in spatial neglect: Effects on visual search depend on auditory spatial performance

Research on spatial neglect predominantly focuses on the visual domain, often conceptualising cross-modal spatial cueing as a potential means to ameliorate visuospatial performance. As spatial neglect can affect multiple sensory modalities, it is unclear how patients with different profiles (e.g., those with visual neglect only versus those with additional auditory neglect) respond to these cues. This study thus investigated the effects of cross-modal spatial cueing in spatial neglect, considering the role of auditory spatial impairment. A total of 60 participants were included, comprising 40 right-hemispheric stroke patients presenting with (V+) or without (V-) visual neglect and 20 healthy controls. Based on the performance in an auditory spatial localisation task, V+ patients were subdivided into those with visual neglect only (V + A-) and those with additional auditory neglect (V + A+). Participants completed a visual search task comprising four cueing conditions: congruent, incongruent, mono sound (i.e., a binaural tone with no spatial properties), and no sound. Voxel-based lesion-symptom mapping (VLSM) was conducted to identify neural correlates of impaired auditory localisation. Critically, only V + A- patients benefited from congruent auditory cues, whereas V+A+ patients did not. Across participants, higher auditory localisation accuracy significantly correlated with faster search durations in the congruent condition. VLSM revealed that poorer auditory localisation performance was associated with lesions involving the first and second branches of the right superior longitudinal fasciculus. These findings suggest that the efficacy of auditory cueing in spatial neglect depends on the sensory modalities affected, necessitating multimodal assessments to devise individualised rehabilitation strategies.