The photopigment melanopsin supports reflexive visual functions in people, such as pupil constriction and circadian photoentrainment. What contribution melanopsin makes to conscious visual perception is less studied. We devised a stimulus that targeted melanopsin separately from the cones using pulsed (3-s) spectral modulations around a photopic background. Pupillometry confirmed that the melanopsin stimulus evokes a response different from that produced by cone stimulation. In each of four subjects, a functional MRI response in area V1 was found. This response scaled with melanopic contrast and was not easily explained by imprecision in the silencing of the cones. Twenty additional subjects then observed melanopsin pulses and provided a structured rating of the perceptual experience. Melanopsin stimulation was described as an unpleasant, blurry, minimal brightening that quickly faded. We conclude that isolated stimulation of melanopsin is likely associated with a response within the cortical visual pathway and with an evoked conscious percept.
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http://dx.doi.org/10.1073/pnas.1711522114 | DOI Listing |
Can J Exp Psychol
January 2025
Department of Psychology, University of Western Ontario.
Episodic future thinking is the ability to project the self forward in time to preexperience a potential future event. It has been hypothesized that two components enhance simulations of future events: personal likelihood and event familiarity. Personal likelihood varies depending on the dynamics of personal goals throughout an individual's lifetime.
View Article and Find Full Text PDFJ Voice
January 2025
School of Behavioral and Brain Sciences, Department of Speech, Language, and Hearing, Callier Center for Communication Disorders, University of Texas at Dallas, Richardson, TX; Department of Otolaryngology - Head and Neck Surgery, University of Texas Southwestern Medical Center, Dallas, TX. Electronic address:
Introduction: Patients with primary muscle tension dysphonia (pMTD) commonly report symptoms of vocal effort, fatigue, discomfort, odynophonia, and aberrant vocal quality (eg, vocal strain, hoarseness). However, voice symptoms most salient to pMTD have not been identified. Furthermore, how standard vocal fatigue and vocal tract discomfort indices that capture persistent symptoms-like the Vocal Fatigue Index (VFI) and Vocal Tract Discomfort Scale (VTDS)-relate to acute symptoms experienced at the time of the voice evaluation is unclear.
View Article and Find Full Text PDFJ Vis
January 2025
Department of Communicative Disorders, University of Alabama, Tuscaloosa, AL, USA.
The visual environment of sign language users is markedly distinct in its spatiotemporal parameters compared to that of non-signers. Although the importance of temporal and spectral resolution in the auditory modality for language development is well established, the spectrotemporal parameters of visual attention necessary for sign language comprehension remain less understood. This study investigates visual temporal resolution in learners of American Sign Language (ASL) at various stages of acquisition to determine how experience with sign language affects perceptual sampling.
View Article and Find Full Text PDFAm J Psychiatry
January 2025
Department of Psychiatry, Center for the Neuroscience of Psychedelics, Massachusetts General Hospital, Boston (Ghaznavi, King, Rosenbaum); Department of Cardiology, Massachusetts General Hospital, Boston (Ruskin); Department of Psychiatry and Neurology, Chemical Neurobiology Laboratory, Center for the Neuroscience of Psychedelics, Massachusetts General Hospital, Boston (Haggerty); Havard Medical School, Boston (Ghaznavi, Ruskin, Haggerty, King, Rosenbaum).
The last few years have seen exponential growth in interest, investment, advocacy, and research into psychedelics as therapeutics. This reflects an optimism about the potential promise of psychedelics as therapeutics. As with all therapeutic interventions, research is needed not only into their benefits but also potential risks.
View Article and Find Full Text PDFPublic Health Nurs
December 2024
Department of Gerontology and Health Care Management, College of Nursing, Chang Gung University of Science and Technology, Taoyuan, Taiwan.
Objective: To develop and implement a tiered training model for neighborhood caregiving volunteers and to evaluate its impact on participants' knowledge, behaviors, and attitudes toward caregiving services.
Design And Methods: We employed a mixed-methods research design. Participants included 32 neighborhood care volunteers and six seed volunteers.
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