The effects of Twiddle muff vs. physical restraints on facial emotions of hospitalized cognitively impaired persons

Several studies have reported adverse effects of physical restraints use. In the United Kingdom, the Twiddle muff has attracted attention as an alternative intervention, with similar reports in Japan. This study evaluated the effects of Twiddle muffs using artificial intelligence (AI)-based facial emotion analysis and the Faces Rating Scale.

Fourteen patients who had undergone physical restraints and dementia care rounds at our hospital were enrolled between February and July 2025. The participants were classified into Delirium and Non-Delirium Group using the Delirium Rating Scale-Revised-98 (cutoff score: 14.5). Facial expressions were recorded for one minute during both physical restraints and Twiddle muff use.

Emotions were categorised as Neutral, Happy, Sad, Angry, and Surprised. AI-based facial emotion analysis showed a decrease in Neutral scores in all patients during Twiddle muff use. In the Delirium Group, Neutral scores decreased, whereas Sad scores increased.

In contrast, in the Non-Delirium Group, Neutral scores decreased and Happy scores increased. The Faces Rating Scale indicated reduced distress with Twiddle muff use. These findings suggest that Twiddle muffs may elicit different emotional responses depending on clinical status and could promote favourable emotional changes, particularly in patients without delirium.

The authors gratefully acknowledge Vitalify Asia for technical support and Editage (www.editage.jp) for English language editing. This work was supported by JSPS KAKENHI Grant Number JP23K10510. Department of Rehabilitation Medicine, Nara Medical University, 840 Shijo-Cho, Kashihara, Nara, 634-8521, Japan Shogo Sasaki, Naoto Seriu, Tetsuro Kitamura, Yukako Ishida, Yasuyo Kobayashi, Yusuke Inagaki & Akira Kido Department of Nursing, Psychiatric Center, Nara Medical University Hospital, 840 Shijo-Cho, Kashihara, Nara, 634-8521, Japan Center for Health Control, Nara Medical University Hospital, 840 Shijo-Cho, Kashihara, Nara, 634-8521, Japan Department of Psychiatry, Nara Medical University, 840 Shijo-Cho, Kashihara, Nara, 634-8521, Japan Department of Neurosurgery, Nara Medical University Hospital, 840 Shijo-Cho, Kashihara, Nara, 634-8521, Japan The authors declare no competing interests.

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