Electrophysiological measures of sensory-motor tasks in patients with depression and possible correlation with sex hormones

STUDY PROCEDURE AND DATA COLLECTION

The study will be conducted after obtaining written informed consent from patients and controls, which includes 64 patients with depression (both males and females) and 40 healthy male and female subjects aged 18 to 45 years. Subjects who meet the inclusion criteria will be recruited. The study procedure will be explained to the participants. Using a randomization method, 64 depressed patients will be divided into two groups: 32 patients will receive Binaural Beats, while the other 32 will not receive Binaural Beats and will only receive pink noise. Of the 40 healthy controls, 20 will be given Binaural Beats and 20 will receive pink noise. Saliva samples for estrogen and progesterone will be collected from female patients, who will be asked to revisit the outpatient department according to the next phase of their menstrual cycle. The saliva samples will be frozen and subsequently analyzed for estrogen and progesterone using ELISA kits.

The experiment consists of three sessions. In the first part, baseline EEG will be recorded for 10 minutes using RMS Superspec 32 equipment with 32 channels simultaneously with EEG. The spectral power in different EEG frequency bands of depression patients will be compared with healthy subjects. After the baseline recording, a saliva sample will be taken. Following that, a 5-minute resting period will be given to the participant. In the second part, the participant will receive auditory sensory stimuli in the form of binaural beats in the theta band at 5-7 Hz. Binaural beats will be generated by publicly available software or applications, using a 400 Hz standard tone in the left ear and a 407 Hz tone in the right ear, played through earphones for 20 minutes. Attention and psychomotor tasks (Trail Making Task) will be assessed before and after the auditory sensory stimuli. Part A involves connecting a series of 25 circles with numbers 1 to 25 in ascending order. Part B involves connecting 25 circles with alternating numbers and letters (1-A, 2-B) in sequence. This test will assess psychomotor speed and attention. It will be followed by a five-minute rest. In the third part, motor assessment will be conducted using a hand grip test and finger tapping for fine motor activity over 5 minutes, while EEG is recorded simultaneously. In the hand grip test, the maximum power of the subject is assessed with a dynamometer, and 33% of that power will be set for 1 minute while simultaneous EEG recording is performed for 5 minutes to assess muscular function. The finger tapping test requires pressing keyboard buttons with the right and left index fingers without moving the entire hand for 10 seconds, while the number of taps is counted by software to determine fine motor activity.