ArticleCerebral cortex (New York, N.Y. : 1991)2015
Phosphene Perception Relates to Visual Cortex Glutamate Levels and Covaries with Atypical Visuospatial Awareness.
Article in Cerebral cortex (New York, N.Y. : 1991), 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 21 papers.
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Who cites it
21 citing papers in PubMed, 53 citations in OpenAlex.
- Age and visual cortex inhibition: a TMS-MRS study.Cerebral cortex (New York, N.Y. : 1991) · 2024Article
- Computational model links normalization to chemoarchitecture in the human visual system.Science advances · 2024Article
- Phosphene Attributes Depend on Frequency and Intensity of Retinal tACS.Physiological research · 2022Article
- Continuous and intermittent theta burst stimulation to the visual cortex do not alter GABA and glutamate concentrations measured by magnetic resonance spectroscopy.Brain and behavior · 2022Article
- The relation between parietal GABA concentration and numerical skills.Scientific reports · 2021Article
- What is the Link Between Mental Imagery and Sensory Sensitivity? Insights from Aphantasia.Perception · 2021Article
- Predicting learning and achievement using GABA and glutamate concentrations in human development.PLoS biology · 2021Article
- The impact of a lack of mathematical education on brain development and future attainment.Proceedings of the National Academy of Sciences of the United States of America · 2021Article
- Inducing lateralized phosphenes over the occipital lobe using transcranial magnetic stimulation to navigate a virtual environment.PloS one · 2021Article
- Assessing differential effects of single and accelerated low-frequency rTMS to the visual cortex on GABA and glutamate concentrations.Brain and behavior · 2020Article
- Article
- Neurophenomenology of induced and natural synaesthesia.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2019Review
- Acquired synaesthesia following 2C-B use.Psychopharmacology · 2019Article
- Assessing Lateral Interaction in the Synesthetic Visual Brain.Vision (Basel, Switzerland) · 2019Article
- Grapheme-Color Synesthesia is Associated with PTSD Among Deployed Veterans: Confirmation of Previous Findings and Need for Additional Research.International journal of emergency mental health · 2019Article
- Glutamatergic facilitation of neural responses in MT enhances motion perception in humans.NeuroImage · 2019Article
- Assessing the Psychedelic "After-Glow" in Ayahuasca Users: Post-Acute Neurometabolic and Functional Connectivity Changes Are Associated with Enhanced Mindfulness Capacities.The international journal of neuropsychopharmacology · 2017Article
- Effect of age and the APOE gene on metabolite concentrations in the posterior cingulate cortex.NeuroImage · 2017Article
- The Emergence of Synaesthesia in a Neuronal Network Model via Changes in Perceptual Sensitivity and Plasticity.PLoS computational biology · 2016Article
- Linking GABA and glutamate levels to cognitive skill acquisition during development.Human brain mapping · 2015Article
Corrections and comments
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Authors and funding
6 authors at 2 institutions in 2 countries.
Funding
Abstract
Phosphenes are illusory visual percepts produced by the application of transcranial magnetic stimulation to occipital cortex. Phosphene thresholds, the minimum stimulation intensity required to reliably produce phosphenes, are widely used as an index of cortical excitability. However, the neural basis of phosphene thresholds and their relationship to individual differences in visual cognition are poorly understood. Here, we investigated the neurochemical basis of phosphene perception by measuring basal GABA and glutamate levels in primary visual cortex using magnetic resonance spectroscopy. We further examined whether phosphene thresholds would relate to the visuospatial phenomenology of grapheme-color synesthesia, a condition characterized by atypical binding and involuntary color photisms. Phosphene thresholds negatively correlated with glutamate concentrations in visual cortex, with lower thresholds associated with elevated glutamate. This relationship was robust, present in both controls and synesthetes, and exhibited neurochemical, topographic, and threshold specificity. Projector synesthetes, who experience color photisms as spatially colocalized with inducing graphemes, displayed lower phosphene thresholds than associator synesthetes, who experience photisms as internal images, with both exhibiting lower thresholds than controls. These results suggest that phosphene perception is driven by interindividual variation in glutamatergic activity in primary visual cortex and relates to cortical processes underlying individual differences in visuospatial awareness.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.