Clinical Effects of a Multisensory Intervention on Communicative Skills in Patients with Severe Acquired Brain Injury: A Multiple Case Study

Introduction: Severe Acquired Brain Injury (SBI) often results in profound impairments in consciousness and communicative engagement. Traditional rehabilitation frequently lacks tools specifically designed to bridge the gap between basic sensory stimulation and active social interaction. The Crdl, a Dutch haptic-based assistive technology, transforms skin-to-skin contact into auditory feedback, potentially facilitating non-verbal communication. Objective: This study aimed to evaluate the efficacy of sound-haptic multisensory stimulation in promoting the recovery of communicative skills, including attention span, eye contact, communicative initiative (turn-taking), and voluntary motor/verbal responses in patients with SBI. Materials and Methods: A multiple-case study design was employed within the Neurorehabilitation Unit of San Bortolo Hospital in Vicenza. The intervention consisted of daily 10–20-minute sessions with the Crdl device. Data were collected via an automated computational tool to quantify target responses (voluntary interactions and turn-taking) and clinical scales, including the Level of Cognitive Functioning (LCF) and Coma/ Near Coma scale (CNC). Absolute behavioural counts were normalized into rates per minute to ensure mathematical comparability. Linear regression models and independent samples t-tests were used to analyse longitudinal progression and differences between early and late intervention phases. Target Population: The cohort consisted of three patients with heterogeneous clinical profiles aged 14, 36, and 64 years, presenting with moderate-to-severe SBI. Results: Statistical analysis of the combined cohort revealed a significant difference in target response rates between the early and late intervention phases (p < .001). The results show an overall increase of responses, communicative engagement, attention time since the introduction of the Crdl in all the analysed cases. Conclusion: Multisensory stimulation represents a powerful clinical bridge for re-establishing a communicative channel in patients with SBI. This approach acts as a motivational catalyst, enhancing the velocity of communicative recovery. These results suggest that integrating multisensory protocols into traditional therapy provides a framework for emotional and relational engagement. Further research with larger samples is necessary to standardize these non-verbal communication protocols in neurorehabilitation.