Online research in philosophy

How should we count people who have two cerebral hemispheres that cooperate to support one mental life at the level required for personhood even though each hemisphere can be disconnected from the other and support its “own” divergent mental life at that level? On the standard method of counting people, there is only one person sitting in your chair and thinking your thoughts even if you have two cerebral hemispheres of this kind. Is this method accurate? In this paper, I argue that it is not, and I advocate an alternative I call the Multiple Person View.

Stoerig links blindsight to lesions between the primary visual cortex and the extravisual cortex. A parallel 'blindsight' occurs when input from the primary visual cortex is blocked during eye movements, convergence and blinks. At such moments (i) conscious vision based upon retinal input is blocked, (ii), however, like in blind sight retinal input can be used in motor tasks. The main difference to blindsight is that we are not only blind but cannot even with deliberate attention bring this blindness into awareness. We are doubly unaware: unaware of being blind and unaware that in spite of this that what we can see is created by the posterior parietal cortex substituting output (for that temporarily not coming from the primary visual cortex) for higher areas of the cerebral cortex.

In this commentary we argue that evolution of the human brain to host the language system was accomplished by the selective development of frontal and temporal areas in the left hemisphere. The unilateral development of Broca's and Wernicke's areas could have resulted from one or more transcription factors that have an expression pattern restricted to the left hemisphere.

A lesion of striate cortex, area V1, produces blindness in the retinotopically corresponding part of the visual field, although in some cases visual abilities in the blind field remain that are paradoxically devoid of conscious visual percepts ("blindsight"). Here we demonstrate that the blindsight subject GY can experience visual sensations of phosphenes in his blind field induced by transcranial magnetic stimulation (TMS). Such blind field percepts could only be induced when stimulation was applied bilaterally, i.e. over GY's area V5/MT in both hemispheres. Consistent with an earlier report [Cowey, A., & Walsh, V. (2000). Magnetically induced phosphenes in sighted, blind and blindsighted observers. Neuroreport, 11, 3269-3273], GY never experienced phosphenes when stimulation was restricted to his ipsilesional V5/MT. To the best of our knowledge this is the first time GY has experienced visual qualia in his blind hemifield. The present report characterizes the necessary conditions for such conscious experience in his hemianopic visual field and interprets them as demonstrating that only via a contribution from GY's intact hemisphere can activation in the damaged hemisphere reach visual awareness.

The neuropsychological and functional characterisation of mental state attribution (‘‘theory of mind’’ (ToM)) has been the focus of several recent studies. The literature contains opposing views on the functional specificity of ToM and on the neuroanatomical structures most relevant to ToM. Studies with brain-lesioned patients have consistently found ToM deficits associated with unilateral right hemisphere damage (RHD). Also, functional imaging performed with non-braininjured adults implicates several specific neural regions, many of which are located in the right hemisphere. The present study examined the separation of ToM impairment from other deficits associated with brain injury. We tested 11 patients with unilateral right hemisphere damage (RHD) and 20 normal controls (NC) on a..