Abstract
Transcranial infrared laser stimulation (TILS) at 1064 nm, 250 mW/cm2 has been proven safe and effective for increasing neurocognitive functions in young adults in controlled studies using photobiomodulation of the right prefrontal cortex. The objective of this pilot study was to determine whether there is any effect from TILS on neurocognitive function in older adults with subjective memory complaint at risk for cognitive decline (e.g., increased carotid artery intima-media thickness or mild traumatic brain injury). We investigated the cognitive effects of TILS in older adults (ages 49–90, n = 12) using prefrontal cortex measures of attention (psychomotor vigilance task (PVT)) and memory (delayed match to sample (DMS)), carotid artery intima-media thickness (measured by ultrasound), and evaluated the potential neural mechanisms mediating the cognitive effects of TILS using exploratory brain studies of electroencephalography (EEG, n = 6) and functional magnetic resonance imaging (fMRI, n = 6). Cognitive performance, age, and carotid artery intima-media thickness were highly correlated, but all participants improved in all cognitive measures after TILS treatments. Baseline vs. chronic (five weekly sessions, 8 min each) comparisons of mean cognitive scores all showed improvements, significant for PVT reaction time (p < 0.001), PVT lapses (p < 0.001), and DMS correct responses (p < 0.05). The neural studies also showed for the first time that TILS increases resting-state EEG alpha, beta, and gamma power and promotes more efficient prefrontal blood-oxygen-level-dependent (BOLD)-fMRI response. Importantly, no adverse effects were found. These preliminary findings support the use of TILS for larger randomized clinical trials with this non-invasive approach to augment neurocognitive function in older people to combat aging-related and vascular disease-related cognitive decline.
Similar content being viewed by others
References
Anders JJ, Moges H, Wu X, Erbele ID, Alberico SL, Saidu EK, Smith JT, Pryor BA (2014) In vitro and in vivo optimization of infrared laser treatment for injured peripheral nerves. Lasers Surg Med 46(1):34–45
Anders JJ, Lanzafame RJ, Arany PR (2015) Low-level light/laser therapy versus photobiomodulation therapy. Photomed Laser Surg 33(4):183–184
Karu TI, Pyatibrat LV, Kolyakov SF, Afanasyeva NI (2005) Absorption measurements of a cell monolayer relevant to phototherapy: reduction of cytochrome c oxidase under near IR radiation. J Photochem Photobiol B Biol 81:98–106
Wong-Riley MT, Liang HL, Eells JT, Chance B, Henry MM, Buchmann E, Kane M, Whelan HT (2005) Photobiomodulation directly benefits primary neurons functionally inactivated by toxins: role of cytochrome c oxidase. J Biol Chem 280:4761–4771
Rojas JC, Lee J, John JM, Gonzalez-Lima F (2008) Neuroprotective effects of near-infrared light in an in vivo model of mitochondrial optic neuropathy. J Neurosci 28(50):13511–13521
Rojas JC, Bruchey AK, Gonzalez-Lima F (2012) Low-level light therapy improves cortical metabolic capacity and memory retention. J Alzheimers Dis 32:741–752
Wang X, Tian F, Soni SS, Gonzalez-Lima F, Liu H (2016) Interplay between up-regulation of cytochrome-c-oxidase and hemoglobin oxygenation induced by near-infrared laser. Sci Rep 6:30540
Mochizuki-Oda N, Kataoka Y, Cui Y, Yamada H, Heya M, Awazu K (2002) Effects of near-infra-red laser irradiation on adenosine triphosphate and adenosine diphosphate contents of rat brain tissue. Neurosci Lett 323(3):207–210
Rojas JC, Gonzalez-Lima F (2013) Neurological and psychological applications of transcranial lasers and LEDs. Biochem Pharmacol 86:447–457
Rojas JC, Gonzalez-Lima F (2017) Transcranial low-level laser light therapy for neurocognitive enhancement. In: Hamblin MR, de Sousa MVP, Agrawal T (eds) Handbook of low-level laser therapy, 1st edn. Pan Stanford Publishing, Singapore, pp 1057–1076
Hamblin MR (2016) Shining light on the head: photobiomodulation for brain disorders. BBA Clin 6:113–124
Naeser MA, Martin PI, Ho MD, Krengel MH, Bogdanova Y, Knight JA, Yee MK, Zafonte R, Frazier J, Hamblin MR, Koo BB (2016) Transcranial, red/near-infrared light-emitting diode therapy to improve cognition in chronic traumatic brain injury. Photomed Laser Surg 34(12):610–626
Barrett DW, Gonzalez-Lima F (2013) Transcranial infrared laser stimulation produces beneficial cognitive and emotional effects in humans. Neuroscience 230:13–23
Blanco NJ, Maddox WT, Gonzalez-Lima F (2015) Improving executive function using transcranial infrared laser stimulation. J Neuropsychol May 28
Blanco NJ, Saucedo CL, Gonzalez-Lima F (2017) Transcranial infrared laser stimulation improves rule-based, but not information-integration, category learning in humans. Neurobiol Learn Mem 139:69–75
Hwang J, Castelli DM, Gonzalez-Lima F (2016) Cognitive enhancement by transcranial laser stimulation and acute aerobic exercise. Lasers Med Sci 31(6):1151–1160
Disner SG, Beevers CG, Gonzalez-Lima F (2016) Transcranial laser stimulation as neuroenhancement for attention bias modification in adults with elevated depression symptoms. Brain Stimul 9(5):780–787
Wang X, Tian F, Reddy DD, Nalawade SS, Barrett DW, Gonzalez-Lima F, Liu H (2017) Up-regulation of cerebral cytochrome-c-oxidase and hemodynamics by transcranial infrared laser stimulation: a broadband near infrared spectroscopy study. J Cereb Blood Flow Metab (in press).
Tian F, Hase SN, Gonzalez-Lima F, Liu H (2016) Transcranial laser stimulation improves human cerebral oxygenation. Lasers Surg Med 48(4):343–349
Rojas JC, Gonzalez-Lima F (2011) Low-level light therapy of the eye and brain. Eye Brain 3:49–67
Gonzalez-Lima F, Barrett DW (2014) Augmentation of cognitive brain functions with transcranial lasers. Front Syst Neurosci 8:36
Haley AP, Sweet LH, Gunstad J, Forman DE, Poppas A, Paul RH, Tate DF, Cohen RA (2007) Verbal working memory and atherosclerosis in patients with cardiovascular disease. An fMRI study. J Neuroimaging 17(3):227–233
Nguyen-Thanh HT, Benzaquen BS (2009) Screening for subclinical coronary artery disease measuring carotid intima media thickness. Am J Cardiol 104(10):1383–1388
Gonzalez-Lima F, Barksdale BR, Rojas JC (2014) Mitochondrial respiration as a target for neuroprotection and cognitive enhancement. Biochem Pharmacol 88:584–593
Schiffer F, Johnston AL, Ravichandran C, Polcari A, Teicher MH, Webb RH, Hamblin MR (2009) Psychological benefits 2 and 4 weeks after a single treatment with near infrared light to the forehead: a pilot study of 10 patients with major depression and anxiety. Behav Brain Funct 5:46–59
Gonzales MM, Kaur S, Eagan D, Goudarzi KK, Pasha E, Doan D, Tanaka H, Haley AP (2014) Central adiposity and the functional magnetic resonance imaging response to cognitive challenge. Int J Obes 38(9):1193–1199
Palva S, Palva JM (2011) Functional roles of alpha-band phase synchronization in local and large-scale cortical networks. Front Psychol 2:204
Tanaka M, Shigihara Y, Ishii A, Funakura M, Kanai E, Watanabe Y (2012) Effect of mental fatigue on the nervous system: an electroencephalography study. Behav Brain Funct 8:48
Basar E (2013) A review of gamma oscillations in healthy subjects and in cognitive impairment. Int J Psychophysiol 90(2):99–117
Acknowledgements
The authors thank Stephanie Oleson and Alex Birdill, who were instrumental in collecting the fMRI data; Evan Pasha, the carotid ultrasound data; and Revanth Poondla, Angelymar Fuentes, Nadia Abdo, and Veronica Almendarez, the behavioral data. EV was supported by a student research fellowship, and FGL was supported by a faculty research fellowship from the College of Liberals Arts of the University of Texas at Austin. This study was supported in part by grants from the National Institute on Aging (R21 AG055772) and the Darrell K. Royal Research Fund for Alzheimer’s Disease.
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Funding
This study was supported in part by grants from the National Institute on Aging (R21 AG055772) and the Darrell K. Royal Research Fund for Alzheimer’s Disease.
Conflict of interest
The authors declare that they have no conflict of interest.
Research involving human participants
All procedures were approved by the University of Texas at Austin Institutional Review Board (IRB) and were conducted in accordance with the ethical standards of the 1964 Declaration of Helsinki and its later amendments.
Informed consent
Informed consent was obtained from all individual participants included in the study.
Rights and permissions
About this article
Cite this article
Vargas, E., Barrett, D.W., Saucedo, C.L. et al. Beneficial neurocognitive effects of transcranial laser in older adults. Lasers Med Sci 32, 1153–1162 (2017). https://doi.org/10.1007/s10103-017-2221-y
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10103-017-2221-y