Short-term Effects of Transcranial Near-Infrared Photobiomodulation on Motor Performance in Healthy Human Subjects: An Experimental SingleBlind Randomized Clinical Trial

Abstract

Introduction: Transcranial near-infrared photobiomodulation (NIR-PBM) is a new noninvasive procedure which transcranially applies a near-infrared wavelength to the scalp with a laser or a light-emitting diode (LED) source. Improvement in the neurological or psychological symptoms has been reported following light irradiation. However, to our knowledge, there is no study to investigate the effects of transcranial NIR-PBM on motor performance directly. Therefore, the objective of this study was to investigate the short-term effects of transcranial NIR-PBM on motor performance in healthy human subjects. Methods: In this experimental single-blind randomized clinical trial study, 56 right-handed healthy participants, whose ages ranged from 18 to 30, were randomly assigned to (1) Real transcranial NIR-PBMC3 group (n=14), (2) Sham transcranial NIR-PBMC3 group (n=14), (3) Real transcranial NIR-PBMC4 group (n=14), and (4) Sham transcranial NIR-PBMC4 group (n=14). We applied the 808 nm laser with irradiation energy density of 60 J/cm2 and power density of 200 mw/cm2 to the C3 or C4 points of the scalp. The number of finger taps as an indicator of motor performance was assessed by the finger-tapping test (FTT) before and after irradiation of transcranial NIR-PBM on the corresponding points of the scalp for 5 minutes. Results: The results showed that the number of finger taps in both right and left hands following the use of transcranial NIR-PBM in the real transcranial NIR-PBMC3 group significantly increased (P<0.05). Conclusion: We concluded that using transcranial NIR-PBM with a laser source on C3 point of the motor cortex in right-handed healthy people can increase the number of finger taps in both hands as an indicator of motor performance improvement.

Transcranial photobiomodulation changes topology, synchronizability, and complexity of resting state brain networks

“…In the context of non-invasive brain stimulation approaches, a growing number of studies are investigating the effects of low power red to near infrared coherent lights on the brain functions [1][2][3][4][5][6][7][8][9][10][11]. This method has been known as photobiomodulation (PBM) and various studies have applied that as intracranial [12,13] and intranasal [3,8] brain stimulation approaches.…”

“…This method has been known as photobiomodulation (PBM) and various studies have applied that as intracranial [12,13] and intranasal [3,8] brain stimulation approaches. However, a group of studies suggested the applicability of the PBM as a transcranial brain stimulation technique for cognitive and behavioral improvements in health and diseases [5,[7][8][9]. Transcranial PBM (tPBM) emits converge light to one or several specific regions of scalp and modulates brain activity via the transferred light energy to the neural cells [3,5,9,10,14].…”

The effects of transcranial laser photobiomodulation and neuromuscular electrical stimulation in the treatment of post‐stroke dysfunctions

“…The single session of transcranial laser therapy [infrared (808 nm), continuous wave, (5 min, 60 J/cm 2 , and 200 mW/cm 2 ) applied on skull (C3 point—located on the left primary motor cortex)] in healthy subjects showed an increase in the number of finger taps in bilateral upper extremities, indicating improvement of the motor control and performance [38]. In addition, the application of transcranial laser may have potentiated the exercise induced by NMES in the paretic upper limb (wrist extension), resulting in the enhanced manual dexterity due to systemic effects of photobiomodulation.…”

The effect of transcranial photobiomodulation on cognitive function and attentional performance of older women with mild cognitive impairment: a randomized controlled trial

“…In healthy young adults, the right PFC tPBM has been shown to improve memory and attention [40,42]. In the study by Fekri et al (2019), motor performance improved following tPBM [43]. Some electroencephalographic studies have reported changes in absolute power and functional connectivity of the brain.…”

“…In the study by Fekri et al . (2019), motor performance improved following tPBM [ 43 ]. Some electroencephalographic studies have reported changes in absolute power and functional connectivity of the brain.…”