title: Aging reduces the stimulating effect of blue light on cognitive brain functions.
abstract: OBJECTIVE
  Light exposure, particularly blue light, is being recognized as a potent mean to stimulate alertness and cognition in young individuals. Aging is associated with changes in alertness regulation and cognition. Whether the effect of light on cognitive brain function changes with aging is unknown, however.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  Functional Neuroimaging Unit, University of Montreal Geriatric Institute.
  
  
  METHODS
  Sixteen younger (23 ± 4.1 y) and 14 older (61 ± 4.5 y) healthy participants were recruited in the current study.
  
  
  METHODS
  Blue light administration.
  
  
  METHODS
  We used functional magnetic resonance imaging to record brain responses to an auditory working memory task in young and older healthy individuals, alternatively maintained in darkness or exposed to blue light.
  
  
  RESULTS
  Results show that the older brain remains capable of showing sustained responses to light in several brain areas. However, compared to young individuals, the effect of blue light is decreased in the pulvinar, amygdala, and tegmentum as well as in the insular, prefrontal, and occipital cortices in elderly individuals.
  
  
  CONCLUSIONS
  The effect of blue light on brain responses diminishes with aging in areas typically involved in visual functions and in key regions for alertness regulation and higher executive processes. Our findings provide the first indications that the effect of light on cognition may be reduced in healthy aging.
authors.affiliation: Functional Neuroimaging Unit, University of Montreal Geriatric Institute, Montreal, Quebec, Canada ; Center for Advanced Research in Sleep Medicine (CARSM), Hôpital du Sacré-Cœur de Montréal, Montreal, Quebec, QC, Canada ; Department of Psychology, University of Montreal, Montreal, Quebec, Canada.
authors.forename: Véronique
authors.initials: V
authors.lastname: Daneault
authors.affiliation: Centre de recherche Institut universitaire en santé mentale de Québec, Quebec, QC, Canada, G1J2G3.
authors.forename: Marc
authors.initials: M
authors.lastname: Hébert
authors.affiliation: Functional Neuroimaging Unit, University of Montreal Geriatric Institute, Montreal, Quebec, Canada.
authors.forename: Geneviève
authors.initials: G
authors.lastname: Albouy
authors.affiliation: Functional Neuroimaging Unit, University of Montreal Geriatric Institute, Montreal, Quebec, Canada ; Department of Psychology, University of Montreal, Montreal, Quebec, Canada.
authors.forename: Julien
authors.initials: J
authors.lastname: Doyon
authors.affiliation: Center for Advanced Research in Sleep Medicine (CARSM), Hôpital du Sacré-Cœur de Montréal, Montreal, Quebec, QC, Canada.
authors.forename: Marie
authors.initials: M
authors.lastname: Dumont
authors.affiliation: Functional Neuroimaging Unit, University of Montreal Geriatric Institute, Montreal, Quebec, Canada ; Center for Advanced Research in Sleep Medicine (CARSM), Hôpital du Sacré-Cœur de Montréal, Montreal, Quebec, QC, Canada ; Department of Psychology, University of Montreal, Montreal, Quebec, Canada.
authors.forename: Julie
authors.initials: J
authors.lastname: Carrier
authors.affiliation: Functional Neuroimaging Unit, University of Montreal Geriatric Institute, Montreal, Quebec, Canada ; Center for Advanced Research in Sleep Medicine (CARSM), Hôpital du Sacré-Cœur de Montréal, Montreal, Quebec, QC, Canada ; Department of Psychology, University of Montreal, Montreal, Quebec, Canada.
authors.forename: Gilles
authors.initials: G
authors.lastname: Vandewalle
mesh_terms: D000328:Adult; D000375:Aging / Q000502:physiology*; D001143:Arousal / Q000502:physiology / Q000528:radiation effects; D001288:Attention / Q000502:physiology / Q000528:radiation effects; D001921:Brain / Q000502:physiology* / Q000528:radiation effects*; D002386:Cataract; D002540:Cerebral Cortex / Q000187:drug effects / Q000502:physiology; D002940:Circadian Rhythm; D003071:Cognition / Q000502:physiology* / Q000528:radiation effects*; D003116:Color; D003430:Cross-Sectional Studies; D003624:Darkness; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008027:Light; D008279:Magnetic Resonance Imaging; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology / Q000528:radiation effects; D008875:Middle Aged; D059906:Neuroimaging; D011680:Pupil / Q000502:physiology / Q000528:radiation effects; D011792:Quebec; D017299:Rod Opsins / Q000378:metabolism; D011795:Surveys and Questionnaires; D000099210:Melanopsin
chemical_list: D017299:Rod Opsins; D000099210:Melanopsin
keywords: Aging; blue light; circadian; cognition; fMRI; light; melanopsin; nonvisual