Procedure
’ alcohol, alcohol-dependent, AD, alcohol dependence
ELECTROLYTE IMBALANCES
VR cue exposure procedure: The researcher first briefly introduced the experimental procedure to the patients, conducted a simple training for the patients, instructed the patients on the operation method of the VR handle, and instructed the patients to choose a comfortable position to sit on the chair. Alcohol was used to clean the patients’ skin. After the alcohol on the skin surface had evaporated, the BVP sensor was attached to the patients’ middle finger, the SC sensor was attached to the patients’ index finger and ring finger, and the respiratory sensor was attached to the patients’ chest or abdomen. After starting the procedure, the connection status was checked, and the patients were instructed to relax. If the connection status was good, heart rate, skin conductance and respiratory signals were collected for 2 min as baseline physiological index data, and then the patients were asked about alcohol craving by VAS as a baseline subjective assessment. The patients were then given a VR device and given enough time to adapt to the VR environment. After they had adapted, they began to watch the VR cue exposure video. At the same time, olfactory stimulation was provided by real alcohol. During the exposure procedure, a multiparameter biofeedback device was used to collect the patients’ heart rate, skin conductance and respiration, and then the patients’ alcohol craving was asked again by VAS.VR cue exposure was carried out in the hospital ward, and AD patients were permitted to stop the procedure at any time if they felt uncomfortable. After the conclusion of the VR cue exposure, participants were observed for about 10 min to ensure that they did not experience any significant discomfort. The sessions were conducted between 6:00 pm and 8:00 pm, as shown in Fig. 
Flow chart of VR cue exposureTesting procedure: After completion of the acute withdrawal treatment, the alcohol-dependent patients were exposed to the above VR cue exposure (assessment), and the changes in VAS, heart rate, skin conductance, and respiration before and after exposure were recorded. Patients were randomly divided into the study group and the control group using the random number table method. The control group only received conventional clinical treatment for alcohol dependence, that is, benzodiazepines (such as oxazepam tablets) at the start of admission to control the acute withdrawal reaction, as well as high doses of group B and C vitamins, to correct water and electrolyte imbalances, and to improve liver function, and other symptomatic supportive treatments were given. The study group received conventional clinical treatment with the addition of VR cue exposure (treatment), 3 sessions per week (1 day apart) for 8 min. After treatment, a VR cue exposure (assessment) was conducted, and the changes in VAS, heart rate, skin conductance, and respiration before and after the exposure were recorded, as shown in Fig. 
Flow chart of test procedure