Impact of photobiomodulation on the aging brain activity

The NeuroSchool PhD Program of Aix-Marseille University (France) has launched its annual calls for PhD contracts for students with a master's degree in a non-French university and for  international co-supervised PhDs.

This project is one of the proposed projects. Not all proposed projects will be funded, check our website for details.

State of the art: Photobiomodulation (PBM) is a non-invasive technique that uses low-energy light, typically in the red to infrared spectrum, where tissue penetration is optimal. When specific photoreceptors, such as cytochrome c oxidase and calcium channels, are activated, this increases ATP, calcium, and nitric oxide, initiating signaling cascades that promote regeneration and restore homeostasis.

With conventional medicine offering limited solutions for cerebral aging, PBM's ability to reduce inflammation, oxidative stress, and cellular death without side effects is promising. Growing interest surrounds its potential in Alzheimer’s disease (AD), and in cognitive rehabilitation for healthy aging individuals. However, PBM's specific effects on brain activity and their relationship to cognitive performance remain poorly understood.

Our aim is to characterize PBM's effects on brain activity at rest and during tasks, enhancing our understanding of its potential for cognitive improvement in elderly.

Methods: Young (20-30 year-old) and aged (60-80 year-old) participants will be recruited and exposed to weekly sessions of PBM. Cognitive evaluation will be assessed before and after the end of PBM treatment. Electroencephalography (EEG) and pupillometry will be recorded during attentional tasks to assess brain activity and cognitive load.

Objectives: Aim 1 is to assess the impact of PBM on brain activity in elderly with or without subjective cognitive decline, at rest and during a task engaging executive functions and attentional control. EEG-derived criteria include individual α peak frequency, aperiodic exponent, and mental load indices.

Aim 2 is to assess the impact of PBM on attentional performance and executive functions in elderly with or without subjective cognitive decline. Performance on a dual cognitive-cognitive task will be evaluated before and after PBM, using reaction times and rate of correct answers

Expected results: Although PBM is being tested in Alzheimer’s trials, its mechanisms remain unclear, especially how it alters brain activity to improve cognition in older adults with cognitive decline. This study aims to address these gaps by identifying the effects of PBM on brain activity and executive functions in elderly. The findings will contribute to a more targeted and effective use of PBM for treating cognitive deficits, paving the way for tangible advancements in managing aging and AD.

Feasibility:

The project has been sent to the CPP and is currently under revision (2024-A02557-40).

The laboratory (CRPN) offers all the tools and expertise required for this project, including a dedicated human experimentation platform and comprehensive IT support services.

Within Aix Marseille Université, NeuroMarseille brings together 8 research laboratories and NeuroSchool, a graduate school in neuroscience, to increase the attractiveness of the university, international collaborations, interdisciplinarity, links with the clinical and industrial worlds and the integration of students into professional life. 

Launched in July 2018, NeuroSchool unifies and harmonizes the training of the third year of the Bachelor of Life Sciences (Neuroscience track), the Master's and the PhD in Neuroscience. 

• Master's degree from a non-French university in neuroscience or related field
• Fluent in English

A B2 level in French is required to communicate with elderly participants who may not speak English.

Experience in EEG analysis and proficiency in Python and/or Matlab programming are appreciated, together with strong foundation in statistics.

The candidate should be highly motivated and fully committed to the project.