May. 14, 2026
1. Core Principle: Photobiomodulation
Photobiomodulation (PBM) uses specific wavelengths of near-infrared and red light to non-invasively penetrate the skull and act on brain cell mitochondria, initiating a series of cellular repair and regeneration processes.
2. Specific Roles of Each Wavelength
Wavelength
Penetration Depth
Core Action Targeting Alzheimer‘s
660nm (Red Light)
2-8mm (Superficial Cortex)
Anti-inflammatory, promotes superficial circulation, protects neurons from oxidative stress
810nm (Near-Infrared)
3-5cm (Deep Cortex)
Activates mitochondrial CCO, increases ATP, reduces Aβ deposition, enhances synaptic plasticity
1050nm (Near-Infrared)
5-7cm (Hippocampus, Basal Ganglia)
Deepest penetration, reaches memory core regions (hippocampus), enhances energy metabolism
3. Five Major Therapeutic Mechanisms Targeting Alzheimer‘s Disease
Mechanism
Mode of Action
Clinical Significance
Mitochondrial Function Enhancement
Activates cytochrome c oxidase, increases ATP synthesis
Improves brain cell energy metabolism, delays neurodegeneration
Aβ Amyloid Protein Reduction
Upregulates Aβ-degrading enzymes, promotes microglial clearance of Aβ
2025 animal studies confirmed 55%-87% reduction in Aβ deposition
Anti-Neuroinflammation
Inhibits microglial activation, reduces pro-inflammatory cytokines (IL-6, TNF-α)
Reduces Alzheimer‘s-related neuroinflammation
Increased Cerebral Blood Flow
Vasodilation, promotes angiogenesis
Improves brain oxygen supply and nutrient delivery
Enhanced Synaptic Plasticity
Promotes BDNF release, enhances neural connections
Slows memory decline
II. Clinical Research Evidence
1. Animal Studies (2025)
Study
Parameters
Key Findings
APP/PS1 Mouse Model
810nm, 25 mW/cm², 20 min/day, 4 weeks
• 55%-87% reduction in Aβ deposition • 72% improvement in behavioral performance • Microglial transformation to anti-inflammatory phenotype
2. Mild Cognitive Impairment Clinical Study (2025)
Parameters
Results
Wavelength: 810nm (pulsed)
• MMSE cognitive score significantly improved (p=0.03)
Frequency: 40 Hz
• Episodic memory (CVLT-II) significantly improved (p=0.02)
Duration: 20 minutes/session
• Default mode network functional connectivity enhanced (p=0.014)
Frequency: 6 times/week
• Plasma IL-6 inflammatory factor decreased (p=0.02)
Course: 6 weeks
• Right thalamic volume increased
3. Alzheimer‘s Disease Clinical Trials (Ongoing)
Study Name
Treatment Protocol
Objective
TRAP-AD Study
808nm, 11 min/session, 3 times/week, 8 weeks
Evaluate cognitive improvement in AD patients
Transcranial PBM for AD
Multiple near-infrared wavelengths, transcranial irradiation of prefrontal cortex
Evaluate cognitive function and quality of life
