Psychedelic Information Theory
Shamanism in the Age of Reason
Search Results : "visual cortex"
Showing 1 to 19 of 19
Role of GABAB receptor-mediated inhibition in reciprocal interareal pathways of rat visual cortex
... and patch-clamp recordings in slices of rat visual cortex we studied the balance of excitation and inhibition in different intracortical pathways. The study was focused on the strength of fast GABAA- and slow GABAB-mediated inhibition in intera...
5-HT2A Agonism and Multisensory Binding
... feedback analysis.14,15 For example, in the visual cortex layer V pyramidal cells are responsible for synchronizing corticothalamic activity with the thalamic nuclei via descending axons; they mediate feedback discrimination in columnar circuit...
What is Nonlinear Hallucination?
... of perspective and edge detection in the visual cortex. Hearing a voice on the television or radio speaking directly to you is a nonlinear destabilization of semantic parsing and sequencing. Skipping time, missing time, or moving sideways or...
The Case Against the Spirit Model of Psychedelic Action
... there must be electrochemical stimulation in the visual cortex. If you are making the case for spirit beings or invisible landscapes that can only be seen under the influence of psychedelics, you are making a case for the human brain having a secret...
Psi-verts and Psychic Piracy: The Future of Parapsychology?
... even found this effect to occur in the visual cortex, the brain region where the effect might be expected if their brains were being stimulated directly[1]. The same effect was also found using functional magnetic resonance imaging (fMRI) ...
... multiscale transforms seem to appear in the visual cortex of mammals. This was an important motivation to further study the application of such transforms to image analysis. To explain the impact of wavelets for lowlevel vision, we concentra...
... smoothed into completed lines and shades in the visual cortex; the image is then passed forward in two divergent projections for spatial and object analysis; and finally the finished image reaches multi-modal convergence in the PFC.18,19 This is a ...
Uncoiling the spiral: Maths and hallucinations
... a mechanism for modelling the workings of the visual cortex too. ...and how the leopard got its spots The first model of pattern formation in animal coats goes back to Alan Turing, better known as the father of modern computer science and B...
... on psychedelics originates in the layers of the visual cortex, but there are other similar inhibitory mechanisms which stabilize sensory cohesion across the entire brain. By applying disinhibition to audio networks, a subject under the influence of...
... grid-like or columnar neural structures of the visual cortex. (Fig. 3) The spontaneous production of geometric hallucinations is due to excitation and loss of stability in these retinal-cortical signal coupling pathways. The transition from seamle...
... of a visual prosthesis for the blind, human visual cortex has been stimulated during a series of surgical procedures on conscious volunteers undergoing other occipital lobe surgery. 2. Area no. 17 seems the most effective locus for such stim...
Effects of LSD on the responses of single units in cat visual cortex
... the activity of single neurones in the primary visual cortex have been studied in cats anaesthetized with urethane. Cells were stimulated with a bright bar of light moved over the receptive field, and orientation tuning was assessed quantitatively...
EEG coherence in post-LSD visual hallucinations
... when coupled with relative isolation of visual cortex, especially upon eye closure, facilitates hallucinations and illusions....
... of subjects with HPPD have shown that when the visual cortex loses coherence with other areas of the brain and coherence among local visual networks increases, spontaneous hallucinations are produced.14 Sensory deprivation for as little as fifteen...
We studied orientation selectivity in V1 of alert monkeys and its relationship to other physiological parameters and to anatomical organization. Single neurons were stimulated with drifting bars or with sinusoidal gratings while compensating for eye ...
Local cortical lesions abolish lateral inhibition at direction selective cells in cat visual cortex
Many cells in the cat visual cortex display a strong selectivity for the direction of motion of an optimally oriented stimulus. Postsynaptic inhibition has been suggested to generate this direction selectivity in simple cells, but the intracortical p...
Recurrent Excitation in Neocortical Circuits
... describes how populations of neurons in cat visual cortex can use excitatory feedback, characterized as an effective "network conductance", to amplify their feedforward input signals and demonstrates how neuronal discharge can be kept proportio...
What Geometric Visual Hallucinations Tell Us about the Visual Cortex
... Here, we summarize a theory of their origin in visual cortex (area V1), based on the assumption that the form of the retino–cortical map and the architecture of V1 determine their geometry. (A much longer and more detailed mathematical version h...
Orientation selectivity in visual cortex by fluctuation-controlled criticality
... neuronal network model of macaque primary visual cortex, we examined how intrinsic dynamic fluctuations in synaptic currents modify the effect of strong recurrent excitation on orientation selectivity. Previously, we showed that, using a s...
Showing 1 to 19 of 19