Chapter 2 -Application of non-invasive neuromodulation technology in sleep medicine research

speaker - Dr. Deng

Live date: June 30, 2022

It is a great honor to invite Dr. Deng from the Medical Technology Department of Peking University Sixth Hospital to give a report in this lecture. The title of the report is: Application of non-invasive neuromodulation technology in sleep medicine research. The following are some excerpts from the live broadcast. (Excerpts from the first-person perspective of the speaker)

Live Broadcast Excerpts

Part 1 Transcranial Magnetic Stimulation

01 Basic Information of Transcranial Magnetic Stimulation

Transcranial magnetic technology is necessary to set standards in the national psychiatric Center.

TMS Mode 

• Single-pulse TMS
• Paired-pulse TMS
• Repetitive transcranial magnetic stimulation, rTMS
• Theta burst stimulation, TBS

The former two modes are mostly used for assessment and diagnosis, and the latter two modes are mostly used for clinical treatment.

TMS Mechanism  

• Regulate the excitability of the cerebral cortex
• Affect neuroplasticity changes
• Altered cerebral blood flow and metabolism
• Affects the secretion of neurotransmitters in brain tissue

Factors Affecting the Effects of rTMS

• Type of coil
• The angle of the coil
• The distance between the coil and the cortex
• The waveform of the pulsed magnetic field
• The frequency of stimulation
• The intensity of stimulation
• Stimulus protocol
• Stimulus time

02 TMS Therapy for Sleep Disorders

Treatment program

Stimulus targets: right dorsolateral prefrontal cortex, right parietal cortex;

Stimulus frequency: low frequency 1HZ;

Total pulses: 1500 pulses;

Number of treatments: more than 10 times.

Literature Case Sharing—Low Frequency 

• The effect of rTMS combined with drugs is better than that of drugs used only;
• After two weeks of rTMS treatment for primary insomnia, the scoring indicators improved, and the improvement of PSQI indicators (Pittsburgh Sleep Quality Index) was maintained until one month later;
• rTMS treats insomnia with anxiety, the study found that the improvement of anxiety is positively correlated with the improvement of depression.

Literature Case Sharing—High Frequency 

• High-frequency rTMS improves excessive sleepiness in adolescents with depression;
• High-frequency rTMS improves sleep quality in drug-dependent patients during withdrawal.

Part 2 Transcranial Electrical Stimulation

01 Basic Information on Transcranial Electrical Stimulation

Classification of Transcranial Electrical Stimulation

• Transcranial direct current stimulation (tDCS)
• Transcranial alternating current stimulation (tACS)

Principle of Transcranial Electrical Stimulation

Unlike other non-invasive brain stimulation techniques such as transcranial electrical stimulation and transcranial magnetic stimulation, tDCS does not cause neuronal firing through suprathreshold stimulation, but works by modulating the activity of neural networks. At the neuron level, the basic mechanism of tDCS regulation of cortical excitability is the change of resting membrane potential hyperpolarization or depolarization depending on the polarity of the stimulus. Anodal stimulation usually increases the excitability of the cortex, while cathodal stimulation decreases the excitability of the cortex.

Subsequent Effects of tDCS

• The maintenance time of subsequent effects of tDCS is different for different durations;
• If the stimulation time is maintained long enough, the cortical excitability can be changed up to 1 hour after the stimulation;
• Within a certain range, the longer the stimulation time, the longer the duration of the subsequent effect.

General clinical application of stimulation for 20min

02 Transcranial Electrical Stimulation for Sleep Disorders

Literature sharing  

• Single bilateral anodal tDCS reduces the sleep efficiency and total sleep time of healthy people, while bilateral cathodic tDCS and cathodic tDCS have no effect on healthy people's sleep;
• Single bilateral anodal tDCS and cathodal tDCS have no effect on sleep in patients with insomnia disorders;
• Four consecutive weeks of left DLPFC positive tDCS can effectively improve the sleep quality of patients with depressive disorder;
• Three consecutive weeks of left DLPFC anodal tDCS effectively improved sleep quality in patients with bipolar disorder;
• so-tDCS increases deep sleep in patients with insomnia disorders;
• tACS can improve sleep quality and increase total sleep time in patients with insomnia.

This series of lectures is a project jointly carried out by Brain Hacker, the Mental Rehabilitation Assistance Group of the Psychiatric Branch of the Chinese Medical Association, the Physical Therapy Group of the Psychiatric Branch of the Guangdong Medical Association, and the Rehabilitation and Physical Therapy Professional Group of the Psychiatrist Branch of the Guangdong Medical Doctor Association. Numerous experts from the field of non-invasive brain neuromodulation will share their research results and clinical experience on the Brain Hacker live broadcast platform.

Note: The above content is part of the text without changing the original meaning from the speakers. To watch the full live video (in Chinese), please go to Live Broadcast Entrance.