Online research in philosophy

Summary Transsexuals are individuals who identify as a member of the gender opposite to that which they are born. Many transsexuals report that they have always had a feeling of a mismatch between their inner gender-based ‘‘body image’’ and that of their body’s actual physical form. Often transsexuals undergo gender reassignment surgery to convert their bodies to the sex they feel they should have been born. The vivid sensation of still having a limb although it has been amputated, a phantom (...) limb, was first described by Weir Mitchell over a century ago. The same phenomenon is also occurs after amputation of the penis or a breast. Around 60% of men who have had to have their penis amputated for cancer will experience a phantom penis. It has recently been shown that a significant factor in these phantom sensations is ‘‘cross-activation’’ between the de-afferented cortex and surrounding areas. Despite this it also known that much of our body image is innately ‘‘hard-wired’’ into our brains; congenitally limbless patients can still experience phantom sensations. We hypothesise that, perhaps due to a dissociation during embryological development, the brains of transsexuals are ‘‘hard-wired’’ in manner, which is opposite to that of their biological sex. We go on to predict that male-to-female transsexuals will be much less likely to experience a phantom penis than a ‘‘normal’’ man who has had his penis amputated for another reason. The same will be true of female-to-male transsexuals who have had breast removal surgery. We also predict that some female-to-male transsexuals will have a phantom penis even although there is not one physically there. We believe that this is an easily testable hypothesis, which, if correct, would offer insights into both the basis of transsexuality and provide farther evidence that we have a gender specific body image, with a strong innate component that is ‘‘hard-wired’’ into our brains. This would furnish us with a better understanding the mechanism by which nature and nurture interact to link the brain-based internal body image with external sexual morphology.. (shrink)

Summary Apotemnophilia, or body integrity image disorder (BIID), is characterised by a feeling of mismatch between the internal feeling of how one’s body should be and the physical reality of how it actually is. Patients with this condition have an often overwhelming desire for an amputation- of a specific limb at a specific level. Such patients are not psychotic or delusional, however, they do express an inexplicable emotional abhorrence to the limb they wish removed. It is also known that such (...) patients show a left-sided preponderance for their desired amputation. Often they take drastic action to be rid of the offending limb. Given the left-sided bias, emotional rejection and specificity of desired amputation, we suggest that there are clear similarities to be drawn between BIID and somatoparaphrenia. In this rare condition, which follows a right parietal stroke, the patient rejects (usually) his left arm as ‘‘alien’’. We go on to hypothesis that a dysfunction of the right parietal lobe is also the cause of BIID. We suggest that this leads to an uncoupling of the construct of one’s body image in the right parietal lobe from how one’s body physically is. This hypothesis would be amenable to testing by response to cold-water vestibular caloric stimulation, which is known to temporarily treat somatoparaphrenia. It could also be investigated using functional brain imaging and skin conductance response. If correct our hypothesis not only suggests why BIID arises, but also, in caloric stimulation a therapeutic avenue for this chronic and essentially untreatable condition. (shrink)

First Published on: 21 June 2007 To cite this Article: Ramachandran, Vilayanur S., McGeoch, Paul D., Williams, Lisa and Arcilla, Gerard (2007) 'Rapid Relief of Thalamic Pain Syndrome Induced by Vestibular Caloric Stimulation', Neurocase, 13:3, 185 - 188 To link to this article: DOI: 10.1080/13554790701450446 URL: http://dx.doi.org/10.1080/13554790701450446..