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The International Association for the Study of Pain (IASP) defines pain as ‘an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage’ (Merskey & Bogduk, 1994). The IASP definition of pain is unique in that it explicitly recognizes that pain is an experience that can be understood in itself, in an internal way, in contrast to prior definitions (Sternbach, 1968; Mountcastle, 1974) that defined pain in terms of external causal stimuli that are correlated in some way with pain feelings and sensations.

External characterizations of pain based on neuroscientific findings remain influential in the pain literature. For example, according to a leading theory, pain feelings and sensations are externally related to a brain image of the ‘afferent representation of the physiological condition of the body’ (Craig, 2003). Interpreted philosophically, this view of pain is analogous to the traditional rational-metaphysical presupposition that feelings are but ‘sensations or emotions of the soul which are related especially to it,’ as Descartes put it, and thus are features only of the self and not of the world.

But pain is not only a personal feeling adhering to the self but that through my pain I am connected to a felt reality of the world. This world is not a world of causal reasons but a world that tonally flows in a certain direction and manner (Smith, 1986). When a sharp object is painfully cutting me, I experience a feeling of wincing back and away from the object, and in correlation with this feeling-flow the sharp object is felt to have a tonal-flow of flowing forwards, towards and into me in a piercing manner. When pain makes me fearful, I experience a feeling-flow of retreating backwards and away from the existent that is threatening me. The feeling flows backwards in a shrinking and cringing manner; I have the sensation of ‘shrinking and cringing back from’ the threatening existent. When my pain presents the quality of anxiety, my experience does not flow backwards as a ‘retreat from’, but has the directional sense of being suspended over an inner bottomlessness. The feeling flow of anxiety during pain is a flow that hovers before the possibility of flowing in a downward direction. When pain presents angry retaliation, I feel an angry ‘striking back’ towards the pain-affected body-part, and as such flows forwards, towards the limb at which I am angry. It flows forwards in a violently attacking manner. By virtue of correlated tonal and painful flows, the world and I are joined together in an extrarational and sensuously appreciative way.

Instead of only describing the external things to which pain is externally related, it is also possible to describe pain internally by noting other internal determinations of the feelings and sensations with which it is united. Joint internal-external characterizations of pain very roughly map onto neuroscientific evidence showing that our cutaneous nociceptive system differentiates into interoceptive and exteroceptive causal features, such that our interoceptive nociceptive system signals tissue disorders that are inescapable, and causes homeostatic responses, and our exteroceptive nociceptive system extracts meaningful information about events in the world in order to effect behaviors that protect the organism from external threats (Price et al. 2003).

References
Craig AD (2003). A new view of pain as a homeostatic emotion. Trends in neurosciences 26(6): 303–307.

Merskey H, Bogduk N (Eds) (1994). Classification of Chronic Pain (Second Ed.). IASP Press: Seattle, pp 209–214.

Mountcastle VB (1974). Pain and temperature sensibilities. Medical Physiology 13(1): 348–391.

Price DD, Greenspan JD, Dubner R (2003). Neurons involved in the exteroceptive function of pain. Pain, 106(3), 215–219.

Smith Q (1986).The felt meanings of the world: A metaphysics of feeling. Purdue University Press.

Sternbach RA (1968). Pain: A psychophysiological analysis. Academic Press: New York.

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Call for Chapters: ‘Pain Experience and Neuroscience’, Edited Collection, 2014 

You are warmly invited to submit your research chapter for possible inclusion in an edited collection entitled ‘Pain Experience and Neuroscience’. The collection editor is Dr. Simon van Rysewyk. The target publication date is December 2014. Target publisher: MIT Press.

According to the International Association of the Study of Pain, pain is ‘an unpleasant sensory and emotional experience associated with actual or potential tissue damage’. Nociceptor activity induced by a noxious stimulus is not pain even though pain most typically has a peripheral physical cause. Pain is always personal. Many laboratory and clinical studies support the IASP pain definition, and it is widely endorsed in the international pain community. Not all pain is associated with tissue damage (stomach and head ache). Pains present in countless varieties associated with different sensations, imbued with different meanings and strong emotions and cognitions. Pain can have intense, complex features that need to be explained. The discovery of how such varied dimensions of pain experience relate to each other and to the pain-related neural pathways, neurotransmitters, and integrative centers of the brain that support them is a major scientific challenge in the study of pain. How can it be done?

The way to meet this challenge is to integrate knowledge from current models of pain with knowledge and insights from neuroscience, psychology, and humanities. A history of experiential pain investigations does exist. For example, early in the twentieth century, Sir Henry Head, William Landau and George H. Bishop conducted psychophysical studies on qualitative differences between ‘first pain’ and ‘second pain’ and neurophysiological studies on the relationship of these pain sub-types to brain activity. Later, temporal differences between first and second pain were explained in terms of central temporal summation in psychophysiological studies by Donald D. Price and others and Roland Staud. These integrative studies use well-known psychophysical scaling methods (e.g., ratio scales) or, the ‘experiential-phenomenological method’, in studies by Price and colleagues. Other experiential methods that form productive research programs should be considered to model pain experience, such as descriptive experience sampling (DES) (to analyze very brief episodes of experience in natural settings) developed by Russell T. Hurlburt and his colleagues, or the explication interview method to analyze the fine grain of chronic experiences, exemplified in the works of Francisco Varella, Claire Petitmengin, and Pierre Vermersch.

Without a detailed experiential analysis of the qualities of pain, or the qualitative differences between pain sub-types, it is extremely challenging to establish a detailed examination of the neural systems that support such features. Experiential analyses are also essential for the advancement of psychological pain theory and clinical practice. The aim of this edited collection is to contribute towards integrating pain psychology and neuroscience with the humanities in the study of pain.

Target audiences of ‘Pain Experience and Neuroscience’

The expected target audiences of ‘Pain Experience and Neuroscience’ are scientists, researchers, authors, and practitioners currently active in pain science, including the neurosciences and clinical neurosciences, psychology, and the humanities. The target audience will also include various stakeholders, like academic scientists and humanists, research institutes, and individuals interested in pain, including pain patients, their families and significant others, and the huge audience in the public sector comprising health service providers, government agencies, ministries, education institutions, social service providers and other types of government, commercial and not-for-profit agencies.

Intent to submit your chapter

Please indicate your intention to submit a manuscript to Simon with the title of the chapter, and author(s). He will approach a publisher once he has accepted 25 intents to submit.

Please feel free to contact Simon if you have any questions or concerns. Many thanks!

IMPORTANT DATES:

Intent to Submit: December 31, 2013
Full Version: May 31, 2014
Decision Date: July 31, 2014
Final Version: August 31, 2014 

Editor 

Dr. Simon van Rysewyk

Post-Doctoral Fellow, Graduate Institute of Medical Humanities, Taipei Medical University, 250 Wu-Hsing Street, Xin-yi District, Taipei City, Taiwan 110.

email: vanrysewyk@tmu.edu.tw

mobile: +886 916 608 88

Email: vanrysewyk@tmu.edu.tw
http://simonvanrysewyk@wordpress.com
http://utas.academia.edu/SimonvanRysewyk

The intrauterine view of gender identity and sexual orientation

The intrauterine theory of gender identity proposes that gender identity is encoded in brain during intrauterine development (e.g., Savic et al. 2011; Swab, 2007). The brain is thought to develop in the male ‘direction’ through a surge of testosterone on nerve cells, likely in the bed nucleus of the stria terminalis (BSTc) in the limbic system (Chung et al. 2002; Krujiver et al. 2000; Zhou et al. 1995), whereas in the female ‘direction’ this surge is absent. This view of gender identity has been adapted to explain transsexualism: since sexual differentiation of the brain occurs in the second half of pregnancy, and sexual differentiation of the sexual organs occurs in months 1-2 of pregnancy, transsexuality is possible. Thus, the relative masculinization of the brain at birth may not reflect the relative masculinization of the genitals (e.g., Bao & Swab, 2011; Savic et al. 2011; Veale et al. 2010).

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The intrauterine theory implies that transsexualism is entirely dependent on a specific and dedicated neuroanatomical brain ‘module’, the BTSc). At a time during the second half of pregnancy, the BSTc comes ‘on-line’, and sexual  – or transsexual  – identity is thereby formed in the individual.

The intrauterine theory as a maturational theory

As a maturational brain theory, the intrauterine theory assumes functional localization of gender identity as an attribute of a specific brain structure or region (i.e., the BSTc) and its patterns of functional connectivity, rather than its patterns of functional connectivity to other structures or regions, to the whole brain and its external environment (van Rysewyk, 2010). Developmentally, a maturational view assumes establishment of intraregional connections, rather than interregional connectivity. It follows that the intrauterine view implies that transsexualism involves a process of organizing intraregional interactions within the BSTc. The bed nucleus of the STc appears to be critically involved.

Extending the maturational aspect of the intrauterine view to gender development also means that we should observe changes in the response properties of the BSTc during pregnancy as regions within the BSTc interact with each other to establish their functional gender roles. Thus, the onset of transsexual identity during intrauterine development will be associated with reliable changes in several regions in the BSTc.

Gray691

 

 

 

 

 

 

 

 

 

 

ST ‘off-line’

Gray691 (1)

         

 

 

 

 

 

 

 

 

 

ST ‘on-line’; onset of transsexual identity

The intrauterine theory and mind-brain identity theory

Philosophically, the intrauterine view is also highly compatible with mind-brain identity theory, a philosophy of mind and consciousness (van Rysewyk, 2013). Mind-brain identity theory claims that mental states are identical to brain states. This implies that a person’s indubitable sense of gender identity as manifested in real-time feelings, sensations, thoughts and reports made to others of being a woman or a man are numerically identical to specific brain states, possibly states of a single brain structure or region. Are the brain states in question states of one brain structure – the BSTc? It appears not, for Chung et al. (2002) found that significant sexual dimorphism in BSTc size and neuron number does not develop in humans until adulthood. However, most male-to-female (MTF) transsexuals self-report that their feelings of gender dysphoria began in early childhood (e.g., Lawrence, 2003).

Clearly, these important findings are not compatible with the maturation of one brain structure or region, but with inter-regional brain development, of which the BSTc may feature as merely one, but significant, contributor. Thus, following the onset of transsexual identity, there is a reorganization of interactions between different brain structures and regions. This reorganization process could change previously existing mappings between brain structures and regions and their functions. It follows that the same phenomenal sense of gender identity in a person (e.g., recurring feelings of gender dysphoria) could be supported by different neural substrates at different ages during development. This possibility doesn’t necessarily exclude a maturational theory of transsexual identity, since the BSTc may be stimulated to reorganize its intrauterine functional connectivity following appropriate stimulation during postnatal development.

Future experimental questions for the function of the BSTc in gender identity and sexual orientation

1. The extent of BSTc localization in gender identity: how diffuse or focal is BSTc activity that results from gender-identity based stimulation?

2. The extent of BSTc specialization in gender identity: How coarsely or finely-tuned is BSTc activity that results from gender-identity based stimulation?

The inter-regional interaction theory of gender identity assumes that as brain tissue becomes more specialized (i.e., finely-tuned), it will become activated by a narrow range of gender-based experiences. With increased specialization, less extensive areas of brain tissue (BSTc?) will identify with gender-based phenomenology.

References

Bao, A. M., & Swaab, D. F. (2011). Sexual differentiation of the human brain: relation to gender identity, sexual orientation and neuropsychiatric disorders.Frontiers in neuroendocrinology32(2), 214-226.

Chung, W. C., De Vries, G. J., & Swaab, D. F. (2002). Sexual differentiation of the bed nucleus of the stria terminalis in humans may extend into adulthood. Journal of Neuroscience, 22, 1027-1033.

Kruijver, F. P., Zhou, J. N., Pool, C. W., Hofman, M. A., Gooren, L. J., & Swaab, D. F. (2000). Male-to-female transsexuals have female neuron numbers in a limbic nucleus. Journal of Clinical Endocrinology and Metabolism, 85, 2034-2041.

Lawrence, A. A. (2003). Factors associated with satisfaction or regret following male-to-female sex reassignment surgery. Archives of Sexual Behavior, 32, 299-315.

Savic, I., Garcia-Falgueras, A., & Swaab, D. F. (2010). Sexual differentiation of the human brain in relation to gender identity and sexual orientation. Progress in Brain Research, 186, 41-65.

Swaab, D. F. (2007). Sexual differentiation of the brain and behavior. Best Practice & Research Clinical Endocrinology & Metabolism21(3), 431-444.

van Rysewyk, S. (2010). Towards the the developmental pathway of face perception abilities in the human brain. In: A. Freitas-Magalhães (Ed.), ‘Emotional Expression: The Brain and the Face’ (V. II, Second Series), University of Fernando Pessoa Press, Oporto: pp. 111-131.

van Rysewyk, S. (2013). Pain is Mechanism. PhD Dissertation, University of Tasmania.

Veale, J. F., Clarke, D. E., & Lomax, T. C. (2010). Biological and psychosocial correlates of adult gender-variant identities: a review. Personality and Individual Differences48(4), 357-366.

Zhou, J. N., Hofman, M. A., Gooren, L. J., & Swaab, D. F. (1995). A sex difference in the human brain and its relation to transsexuality. Nature, 378, 68-70.

Chemical Brain Preservation: How to Live “Forever” – A Personal View.

It has sometimes been stated that classical music is superior to other forms of music. Why would a person say it? Well, human beings are consummate imitators, and if a person stands to gain by publicly making another copy of it, then imitation – camouflage? – is a strategy for success.

There are other possibilities. Listening to and performing classical music does not conventionally engage the human body in dance. The relative passivity of the body in classical music may therefore signify by default – to some, at least – that this form of music is more cerebral than other forms of music which have a dance component and, therefore, is superior. Certainly, the body produces bodily sensations and perceptions (e.g., propioception). Take those out of the picture, and what is left: mind. We would like to say that very much. Is it correct?

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