Brain Tissue Is Responsive To Light, Says Study
    By News Staff | May 29th 2012 11:14 AM | 3 comments | Print | E-mail | Track Comments

    A recent placebo-controlled study showed evidence of trans-cranial bright light's effect to brain functions when administered through the ear. Bright light stimulation was found to increase activity in brain areas related to processing of visual sensory information and tactile stimuli. The findings are the first ever published scientific article about functional modulation of the brain with bright light delivered to the brain through the ears.

    The study was conducted with 51 healthy test subjects, utilizing functional magnetic resonance imaging (fMRI). Some of the test subjects were given bright light into the ear canals with an optical fibre, and for others the light source was switched off. The eyes of the test subjects were covered during the study so that they were unable to determine which group they belonged to. Optical fiber did not warm up from the influence of light.

    The study setting was typical for brain imaging, and corresponds with a placebo controlled setting. Real time functions of the brain's resting state neural networks were measured in the study with fMRI, making it possible to locate the regions of the brain where the amount of blood and its oxygen saturation change as a result of intervention; in this case as a result of bright light.

    "The research results confirm that it is possible to influence brain functions with bright light delivered directly to the brain through the ear," says researcher TuomoStarck from the Oulu University Hospital. "The group that received bright light demonstrated in the analysis significant increase in neural network activity especially in brain areas connected with visual perception."

    "There is earlier proof of the existence of photosensitive proteins, such as opsins, in the brain. This study confirms light-responsiveness of the brain itself, and that bright light given through the ear canal is a very viable method for influencing mood," says Professor and Leading Senior Physician Timo Takala from Oulu Deaconess Institute.

    According to a second, closely related research result by Oulu University researchers, presented in March at the European Congress of Psychiatry, the human brain contains large amounts of photosensitive OPN4 (melanopsin) receptor protein. The clinical efficacy of bright light therapy for mood disorders when administered through the eye is believed to be based on the photosensitive OPN4-protein that has earlier been found only on the retina.

    "Discovery of the photosensitive OPN4-protein in several parts of the human brain adds to the body of evidence that bright light channeled to the brain directly - and not only through the eyes - increases the activity of brain functions," comments Chief Science Officer Juuso Nissila from the Finnish company Valkee Oy.

    Bright light is considered an effective therapy for treating Seasonal Affective Disorder - bright light is channeled through the ear canal directly to those brain areas that are known to be central in depression, and that have been discovered in studies at the Oulu University to contain photosensitive proteins. 

    Citation: Tuomo Starck, Juuso Nissilä, Antti Aunio, Ahmed Abou-Elseoud, Jukka Remes, Juha Nikkinen, Markku Timonen, Timo Takala, Osmo Tervonen, Vesa Kiviniemi, 'Stimulating brain tissue with bright light alters functional connectivity in brain at the resting state', World Journal of Neuroscience Vol.2 No.2, May 2012 PP.81-90 DOI: 10.4236/wjns.2012.22012


    Tony Fleming
    Individual cells are known to be sensitive to UV light, so it's not surprising that the brain, an interconnection of neurons is sensitive too.
    Tony Fleming Biophotonics Research Institute
    This is highly implausible. What light penetrates the ear drum will only be met with the solid bone encasing the middle ear. Even if any light were still able to penetrate the bone, look up any anatomical drawing of the human skull and you’ll see that the inner ears lie beneath the lowest point of the temporal lobe. In other words, the light wouldn’t even be hitting the brain. Considering all of the above, even if the light somehow does manage to reach the brain, the existence of photoreceptive cells in the brain that can be stimulated by direct light exposure is questionable.

    In addition, there are serious conflicts of interest for a number of authors of the study. The 2nd and 3rd authors are CEOs of a company selling a (very expensive) device that claims that by using its product to shine LED lights into your ears, you can treat Seasonal Affective Disorder (SAD). 2 other authors (including Takala) are shareholders of this company, and the lead author is a live-in partner of an employee of the company. You’ll also notice that these authors have a hand in every single study making similar claims. In other words, they have no independent evidence supporting their claims.

    I’m an auduologist and I shine lights into peoples’ ears for a living. Perhaps I should start charging an additional fee for “mood influencing properties”.

    Tony Fleming
    Read Alexander Gurwitsch's 'mitogenetic' radiation, Ross Adey's 'window effect' and finally Fritz-Albert Popp's biophotonics. Sorry the last link is German but you can find other sites via google on his name. Basically, what I'm saying is that pretty much ALL cells of the body operate in the UV range. The DNA operates in this range as a frequency, more particularly metaphase occurs at these frequencies. This is merely a comment that relates to other work going back to the 1920's through the 1970's and on till today that relates UV with cells. 

    On another front,  light definitely does has a mood altering impact.

    It is thought the pores of the skin can be a conduit of photons from outside to inside e.g. Ampullae of Lorenzini in Elasmobranch marine species where electrical signals form a means of predation. Our pores appear to be an evolutionary 'throwback' to the days when we mammals were marine species.

    This work and your audiology tests are other ways that the brain is stimulates other than internal biophotonic mechanisms.
    Tony Fleming Biophotonics Research Institute