The pupillary light response is an important automatic physiological response which optimizes light reaching the retina. Recent work has shown that the pupil also adjusts in response to illusory brightness and a range of cognitive functions, however, it remains unclear what exactly drives these endogenous changes. Here, we show that the imagery pupillary light response correlates with objective measures of sensory imagery strength. Further, the trial-by-trial phenomenological vividness of visual imagery is tracked by the imagery pupillary light response. We also demonstrated that a group of individuals without visual imagery (aphantasia) do not show any significant evidence of an imagery pupillary light response, however they do show perceptual pupil light responses and pupil dilation with larger cognitive load. Our results provide evidence that the pupillary light response indexes the sensory strength of visual imagery. This work also provides the first physiological validation of aphantasia.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9018072 | PMC |
http://dx.doi.org/10.7554/eLife.72484 | DOI Listing |
PLoS One
January 2025
Department of Convergence of Healthcare and Medicine, Ajou University Graduate School of Medicine, Suwon, South Korea.
Brain herniation can be a life-threatening condition, resulting in poor prognosis and higher fatality rates. We examined whether quantitative characteristics of sequential pupillary light reflex (PLR) could serve as biomarkers for identifying brain herniation in fatal acute stroke cases with anterior circulation involvement admitted to neurological intensive care unit (Neuro-ICU). Automatic pupillometer assessed PLR automatically every 4-6 hours, measuring eight specific features: NPi (Neurological pupil index) score, initial resting and constriction pupil size, constriction change, constriction velocity, constriction latency, and dilation velocity.
View Article and Find Full Text PDFCephalalgia
January 2025
Department of Pharmacology, University of Arizona, Tucson, USA.
Purpose: Photophobia is a common and debilitating symptom associated with migraine. Women are disproportionately affected by migraines, with a higher prevalence and more severe symptoms compared to men. This study investigated the effects of cortical spreading depression on light-aversive and dark-seeking behaviors in a rat model, with an emphasis on sex differences.
View Article and Find Full Text PDFComput Biol Med
January 2025
Institute of Informatics, Federal University of Goiás, GO, Brazil.
The Pupillary Light Reflex (PLR) is the involuntary movement of the pupil adapting to lighting conditions. The measurement and qualification of this information have a broad impact in different fields. Thanks to technological advancements and algorithms, obtaining accurate and non-invasive records of pupillary movements is now possible, expanding practical applications.
View Article and Find Full Text PDFCureus
December 2024
Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, JPN.
Acute epidural hematoma is one of the most serious traumatic conditions in neurosurgery, for which emergency surgery may be indicated. Injury to the middle meningeal artery (MMA) is generally the cause of hemorrhage, often accompanied by convexity fractures resulting from head trauma. However, an epidural hematoma by a contusion of the jaw is very rare.
View Article and Find Full Text PDFInvest Ophthalmol Vis Sci
January 2025
Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Purpose: This study aimed to identify a novel recombinant adeno-associated virus (rAAV) capsid variant that can widely transfect the deep retina through intravitreal injection and to assess their effectiveness and safety in gene delivery.
Methods: By adopting the sequences of various cell-penetrating peptides and inserting them into the capsid modification region of AAV2, we generated several novel variants. The green fluorescent protein (GFP)-carrying variants were screened following intravitreal injection.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!