Introduction
Traumatic brain injury (TBI) is a major public health concern that often results in long-term cognitive and psychological impairments. In recent years, transcranial photobiomodulation therapy (PBMT) has emerged as a non-invasive technique with the potential to support neurorehabilitation by enhancing cerebral perfusion and modulating brain activity. A study published in Photobiomodulation, Photomedicine, and Laser Surgery (2019) explored the impact of PBMT on cognitive and psychological functions in patients with chronic severe TBI.
The Intervention
The clinical study evaluated ten individuals with chronic severe TBI who underwent transcranial PBMT sessions three times per week for six weeks. The protocol utilized a device containing 13 clusters of four red-light LEDs, each emitting light at a wavelength of 630 nm. The total area of scalp exposure was approximately 400 cm². The researchers assessed hemodynamic responses and cognitive performance at three different time points: before the intervention, one week after the final session, and three months post-intervention.
Key Findings
Although not statistically significant, the study reported several relevant outcomes:
- Cerebral blood flow and oxygenation increased, especially in the left hemisphere, suggesting enhanced brain oxygenation and potential functional improvements.
- Neurocognitive assessments showed improvements in episodic memory, verbal and visual memory, planning, and processing speed. However, some cognitive tests showed mixed results.
- Psychological outcomes indicated a reduction in depressive symptoms, while anxiety scores slightly increased but remained within minimal levels.
Conclusions
The authors concluded that transcranial PBMT may contribute to cognitive rehabilitation in TBI patients by enhancing cerebral hemodynamics. Despite the small sample size and the absence of a placebo group, the findings suggest that PBMT could be a supportive tool in neurorehabilitation. Further studies with larger and more homogeneous populations are needed to confirm these preliminary results.
Reference: Carneiro AMC, Poiani GC, Zaninnoto AL, Lazo Osorio R, Oliveira ML, Paiva WS, Zângaro RA. Transcranial Photobiomodulation Therapy in the Cognitive Rehabilitation of Patients with Cranioencephalic Trauma. Photobiomodul Photomed Laser Surg. 2019; 37(10):657-666. doi: 10.1089/photob.2019.4683.