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The 15 July 2005 issue of Science has an interesting article regarding something called anosognosia.
It seems very strange that one is unaware of their own paralysis while they are completely aware of the person they are being interviewed by asking them about it. The patient in this case would simply need to look down and realize that when consciously attempting to lift an arm, it would not move.
Similar problems might include the belief that limbs are still attached when in fact they've been amputated. That seems to be a similar phenomena wherein the brain is consciously aware of a limb that simply doesn't exist. Another problem I've seen is people with memory loss not realizing they even have a memory problem or constantly forgetting they have this problem.
If one were to model the brain as a mechanism of some sort with nerve inputs, it would seem that there is a borderline within the brain beyond which conscious awareness can not extend. In other words, if the input/output for the conscious portion of the brain simply goes silent and does not register anything, it would seem as if we can not be consciously aware of it or our consciousness is not impared by it except as that input/output may affect things such as memory.
We often view consciousness as being seated in the brain, but I wonder if there is any evidence which points to some limited location within the brain. The article in Science mentions specific locations, but unfortunately I'm not a neuroscientist and have no idea if this entire concept of there being a specific region of the brain responsible for consciousness has been examined. Any comments would be appreciated.
A strange and disturbing neurological condition, anosognosia, can cause obviously intelligent, awake and talking individuals to be unaware of paralysis on one side of their body. Berti et al. investigated patients with spatial neglect and found that about half of them were also anosognosic for their left hemiplegia because of lesions in the right brain hemisphere. Comparisons of the two groups with and without anosognosia revealed that damage to frontal areas (particularly brain areas 6 and 44, motor cortex BA4, and the somatosensory cortex) underpins the loss of awareness of motor impairment in these patients.
It seems very strange that one is unaware of their own paralysis while they are completely aware of the person they are being interviewed by asking them about it. The patient in this case would simply need to look down and realize that when consciously attempting to lift an arm, it would not move.
Similar problems might include the belief that limbs are still attached when in fact they've been amputated. That seems to be a similar phenomena wherein the brain is consciously aware of a limb that simply doesn't exist. Another problem I've seen is people with memory loss not realizing they even have a memory problem or constantly forgetting they have this problem.
If one were to model the brain as a mechanism of some sort with nerve inputs, it would seem that there is a borderline within the brain beyond which conscious awareness can not extend. In other words, if the input/output for the conscious portion of the brain simply goes silent and does not register anything, it would seem as if we can not be consciously aware of it or our consciousness is not impared by it except as that input/output may affect things such as memory.
We often view consciousness as being seated in the brain, but I wonder if there is any evidence which points to some limited location within the brain. The article in Science mentions specific locations, but unfortunately I'm not a neuroscientist and have no idea if this entire concept of there being a specific region of the brain responsible for consciousness has been examined. Any comments would be appreciated.