The images processed by the phosphene
model correspond to the actual electrode array of visual prosthesis.
Current generations of retinal prostheses return a very basic vision consisting of phosphene
The occurrence of cortical phosphenes
proposed by Kanai et al.
In case of two reports, it was not clear whether the images were seen with open or closed eyes (aurora-like phosphenes
, geometric shapes, fractals).
produced by electrical stimulation of human occipital cortex, and their application to the development of a prosthesis for the blind.
Un intentionnaliste pourrait retorquer que dans la perception il y a bien une marge d'erreur representee par la vaste gamme d'illusions et d'hallucinations perceptives : batons casses dans l'eau, pieces apparemment elliptiques, tours carrees qui "deviennent" rondes, phosphenes
, mirages ...
A history of hypertension, diabetes, or polymyalgia rheumatica points to vascular causes, and hyperthyroidism suggests that flashing lights may be phosphenes
of Graves' disease.
Such experiences of seeing light when light is not actually entering the eye are known as phosphenes
. (The pattern of light you see when you rub your closed eyes is a type of phosphene
One possibility is that rubbing or pressing the eye may stimulate the optic nerve endings and evoke so-called phosphenes
, sensations of light at the cortical level (Fazzi et al., 1999).
It is very common for a people to see such patterns (described as 'phosphenes
' by psychologists) when they first go into trance or when under the influence of hallucinatory drugs (not the case with Cassell).
With effort Charlie sat up, and the simple movement sent whorls of twinkling phosphenes
caroling before his eyes.
On the other hand, this reviewer has noted a number of lapses: Sagona's rather wild speculations concerning shamanism, "phosphenes
," and the neuropsychological underpinnings of Palaeolithic art (pp.