Monthly Archives: January 2012

The Interaction Between Values and Illness: Personality Disorders

One of the categories of Psychiatric illness is the Disorder of Adult Personality. ICD-10 features the Personality Disorder in Section F60-69 and the diagnostic features can be viewed online here. The Personality Disorders are complex and many professionals will spend their entire careers in the study of the Disorder of Personality as well as the clinical management of people who have received this diagnosis. The Personality Disorders are controversial for many reasons. These controversies range from consideration of whether a core feature of our identity can be medicalised through to the accuracy of these labels in describing such an identity across many settings. The overlap between many of the Personality Disorders also presents challenges. Many of these discussions are played out in the establishment of services such as the Dangerous Severe Personality Disorder services. A key feature of Personality Disorders though is that they are maladaptive. In other words in social groups, the Personality Disorder would causes difficulties for the person and others within the group.  Looking at the conditions described in ICD-10 and selecting the Dissocial Personality Disorder, perhaps the most widely known of the Personality Disorders we can see a number of the features including a

Disregard for social obligations

This leads on to the subject of interest – how do values and illness interact? The Personality Disorders are the best example of this interaction. So why would those with a diagnosis of Dissocial Personality Disorder have a ‘disregard for social obligations’? The description of the Personality Disorders leaves a lot of scope for interpretation and the existence of these features is a key part of the diagnosis. Once this is acknowledged the Biological/Psychological/Social Models are invoked and explanations ranging from the immature Cerebral Cortex through to experienced trauma are invoked. However I would argue that there is a key step which is being missed in the movement from identification of features to explanatory models and that is the invocation of capacitious decision-making

A Role for the WillIs there a Volitional Class of Disorders of Adult Personality?

I would argue that with regards to ‘disregard for social obligations’ a key question needs to be asked. Has the person made a conscious decision to hold these values with an understanding of the consequences. In other words are these capacitous values. By considering the will, the ability of a person to make capacitious decisions we can divide people showing a ‘disregard for social obligations’ into two groups – those that have made this out of choice and those that have not. For those that have made the explicit decision to hold these values they could be classed as a ‘Volitional’ Dissocial Personality Disorder. In this case, if the person is seeking help to relate with others their treatment approach would necessitate capacitious decision making with regards to treatment.

Are there Non-Volitional Disorders of Adult Personality?

There are two obvious reasons why a person might hold these values regarding social obligations

1. These values were learnt during a period when the person was non-capacitous – in early childhood for instance. The difficulty here is that disorders of emotion and attachment in Childhood do not necessarily lead to disorders of Adult Personality. Similarly not all people who develop disorders of Adult Personality have experienced difficulties in Childhood. A consideration of age and development issues does not necessarily fully address the subtleties of maladaptive Personality and perhaps would not be expected to given the many experiences we have which are able to shape our Personality. Nevertheless the issue of capacity with regards to values may be useful in areas of scientific enquiry investigating these conditions in more detail.

2. The person does not have the biological apparatus necessary to understand social meaning. Empathy is the construct most relevant to this possibility. If a person lacks the ability to understand another person’s mind then a ‘Disregard for social obligations’ moves away from being a choice to a Disorder of Understanding. Professor Simon Baron-Cohen’s ‘Zero Degrees of Empathy’ explores this subject in more detail. The most widely known disorders of Empathy are the ‘Autistic Spectrum Disorders’ and here there has been a large body of literature exploring underlying neurobiological explanations.

Whilst the above is merely speculation based on a consideration of the issues the subject of how we choose to hold the values we do has many profound implications which extend far beyond discussions of health and illness.

An index of the site can be found here. The page contains links to all of the articles in the blog in chronological order. Twitter: You can follow ‘The Amazing World of Psychiatry’ Twitter by clicking on this link. Podcast: You can listen to this post on Odiogo by clicking on this link (there may be a small delay between publishing of the blog article and the availability of the podcast). It is available for a limited period. TAWOP Channel: You can follow the TAWOP Channel on YouTube by clicking on this link. Responses: If you have any comments, you can leave them below or alternatively e-mail justinmarley17@yahoo.co.uk. Disclaimer: The comments made here represent the opinions of the author and do not represent the profession or any body/organisation. The comments made here are not meant as a source of medical advice and those seeking medical advice are advised to consult with their own doctor. The author is not responsible for the contents of any external sites that are linked to in this blog.

 

 

 

Brodmann Area 22: A Brief Review of the Literature Part 2

Brodmann Area 22, Derived from Gray’s Anatomy 20th Edition 1918 Lithograph Reproduction, Public Domain

 

The brain is a complex structure and but can be organised according to several principles. One approach is to characterise the brain regions according to the microscopic properties of these regions.  More specifically the neurons are organised differently between regions. Some regions may contain unique types of neurons. This approach to understanding the organisation of the brain was proposed by the German Neuropathologist Korbinian Brodmann and resulted in the eponymously named Brodmann Area. There are 52 areas in all and I have covered other Brodmann Areas elsewhere in this Blog. This is the second in a series on one of these areas – Brodmann Area 22. A simple search strategy was adopted. The term ‘Brodmann Area 22′ was used to search in Medline using the PubMed interface. Relevant results were identified and included.

In an EEG study, a specialised method Electromagnetic Tomography was used to create a model of the source of discharges observed on the EEG in 22 subjects during and after a period of running on a treadmill. Fifteen minutes after the end of the exercise, BA22 was one of the regions showing a decrease in Alpha-2, Beta-1 and Gamma activity. The researchers in this study used depth electrode recording and an analysis of functional connectivity to characterise the responses of different areas to amplitude modulation. The researchers concluded that BA22 amongst other areas displayed evidence of response to amplitude modulation in both hemispheres (see also a study freely available here). In this study, researchers looked at people undergoing surgery for Temporal Lobe epilepsy using functional Magnetic Resonance Imaging to examine the functional connectivity between brain regions. They found that higher preoperative coupling between the Hippocampus and BA22 was associated with a postoperative reduction in verbal learning.

People with Schizophrenia were compared to controls in an fMRI study in which the researchers investigated changes in neural activity with an overlearning task. When the tasks become automatic, there are corresponding reductions in the activity in relevant brain regions. The researchers found this characteristic reduction in both controls and the people with Schizophrenia in a number of regions including BA22 suggesting that this method of learning is intact although changes in working memory in people with Schizophrenia have been identified in some studies. Advanced Glycation end products are compounds which accumulate in the brain with aging. In one study, the accumulation of AGE’s in BA22 was assessed in people who had been diagnosed with Alzheimer’s Disease compared to a control group. The researchers found the characteristic accumulation of AGE’s in the former group compared to the control group and this accumulation progressed through the early, middle and later stages of Alzheimer’s Disease.

Appendix

Brodmann Area 22: A Brief Review of the Literature – Part 1

An index of the site can be found here. The page contains links to all of the articles in the blog in chronological order. Twitter: You can follow ‘The Amazing World of Psychiatry’ Twitter by clicking on this link. Podcast: You can listen to this post on Odiogo by clicking on this link (there may be a small delay between publishing of the blog article and the availability of the podcast). It is available for a limited period. TAWOP Channel: You can follow the TAWOP Channel on YouTube by clicking on this link. Responses: If you have any comments, you can leave them below or alternatively e-mail justinmarley17@yahoo.co.uk. Disclaimer: The comments made here represent the opinions of the author and do not represent the profession or any body/organisation. The comments made here are not meant as a source of medical advice and those seeking medical advice are advised to consult with their own doctor. The author is not responsible for the contents of any external sites that are linked to in this blog.

News Roundup: January 2012 4th Edition

In a study at Princeton, researchers surveyed 1,100 students and found that having a family history of psychiatry conditions had a significant correlation with a student’s choice of studies (Benjamin et al, 2012). The researchers found that a student of the humanities was twice as likely to report having a family member with a history of a mood disorder while a student of science or a technical subject were three times more likely to report a sibling with an Autistic Spectrum Disorder.

In one study looking at a model of Rett Syndrome, an X-linked neurodevelopment condition affecting girls researchers found that Brain Derived Neurotrophic Factor (BDNF) was markedly reduced in the brainstem. Since BDNF is needed for maintenance and growth of neurons, the researchers suggest this may be a significant factor in the development of Rett Syndrome. However further research will be needed to test this hypothesis.

There is a very interesting scheme in the West Midlands to raise awareness of Dementia. Dr Kaarim Saad, Clinical and Social Care Lead for Dementia at NHS West Midlands unveiled a series of videos designed as a training tool to help teachers in the West Midlands raise awareness of Dementia in schools. More details can be found at the site above including the videos and presentations.

New guidelines on the neuropathological assessment of Alzheimer’s Disease (Bradley et al, 2012) have been published and are freely available here.

In a longitudinal study published in Neurology, the researchers followed up 1450 older adults over 3 years and found that 72/1000 men developed Mild Cognitive Impairment over this period compared to 56/1000 women (Roberts R et al 2012).

References

Benjamin C. Campbell, Samuel S.-H. Wang. Familial Linkage between Neuropsychiatric Disorders and Intellectual Interests. PLoS ONE, 2012; 7 (1): e30405 DOI:

Bradley T. Hyman et al. National Institute on Aging–Alzheimer’s Association guidelines for the neuropathologic assessment of Alzheimer’s disease. Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association. Volume 8, Issue 1 , Pages 1-13, January 2012.

Roberts R et al. The incidence of MCI differs by subtype and is higher in men: The Mayo Clinic Study of Aging. Neurology published ahead of print January 25, 2012,

An index of the site can be found here. The page contains links to all of the articles in the blog in chronological order. Twitter: You can follow ‘The Amazing World of Psychiatry’ Twitter by clicking on this link. Podcast: You can listen to this post on Odiogo by clicking on this link (there may be a small delay between publishing of the blog article and the availability of the podcast). It is available for a limited period. TAWOP Channel: You can follow the TAWOP Channel on YouTube by clicking on this link. Responses: If you have any comments, you can leave them below or alternatively e-mail justinmarley17@yahoo.co.uk. Disclaimer: The comments made here represent the opinions of the author and do not represent the profession or any body/organisation. The comments made here are not meant as a source of medical advice and those seeking medical advice are advised to consult with their own doctor. The author is not responsible for the contents of any external sites that are linked to in this blog.

Science 4.0. Deconstructing Web 2.0. Harnessing Collective Intelligence

Science 4.0 is a movement resulting from the formation and use of the World Wide Web. Scientists are using the World Wide Web to collaborate and do science in new ways with significant implications. The term Science 4.0 is a special case of the World Wide Web and influenced by Web 2.0. Therefore it is helpful to understand what the Web 2.0 is in order to better understand Science 4.0. The term Web 2.0 was first used at the O’Reilly Media conference and implies a development in the use of the Web. This has been covered in an earlier article in the series (see Appendix).  The Web 2.0 had several characteristics according to this definition and one of these is the harnessing of collective intelligence. This phenomenon is explained in more detail in the original article. I have added two further categories – augmented intelligence and artificial intelligence.

Hypertext Links

Hypertext links are described as a key mechanism for harnessing of collective intelligence in the original article.The use of hypertext links enables people to create links between sites – essentially an online network. To use this Blog as an example – on the right of the screen is a Blogroll which links to other Blogs of relevance. The reader who is interested in the contents of this site will likely be interested in the contents of some of the other Blogs that are linked to. The reader is guided through a ‘path’ on the Web simply by clicking from one Blog to the other. If the other Blog has a Blogroll link then the reader is likely to be guided along a a restricted path. Out of all of the billions of pages on the Web, the ‘path’ followed by clicking on the links between Blogs shuts out a lot of the Web and lets the reader focus on their area of interest. This path is created not just on this blog but through the efforts of all the bloggers represented along the readers chosen pathway. In this way the reader is able to draw on the experience of many bloggers to make sense of the vast Web space.

In some senses this is similar to the experience of undertaking a survey of the research literature. If I wanted to undertake research on a subject I would conduct a search on Medline for articles of relevance. I would be making use of the search engine to identify abstracts of papers which are indexed with tags relevant to my search. Once I have identified the papers, I would then be able to use a secondary manual method which is to search through the citations in the paper as they should be very relevant to the subject and may not have turned up in the original search. Of course, once I have located these articles I can repeat the process to find citations within those articles and so on. Thus I would again be drawing on the experiences of researchers to make sense of the vast research literature that dates back over several centuries. There is a difference with the Web though. In the Web, it is very much easier for a person to publish those links and very much easier for the reader to follow the links. There is therefore a much greater probability that the reader will see what it is that the author is wanting to share. However the author will not be constrained by the space limitations of mainstream publishing and will be able to link to more of the relevant literature if necessary.  In the original article, trackbacks are mentioned also but I think they are too similar to the hypertext links to merit a separate discussion.

Crowdsourcing

The topic of crowdsourcing was discussed a book by Jeff Howe (Howe, 2008) and follows the coining of the term Web 2.0. Although crowdsourcing wasn’t mentioned explicitly in the original O’Reilly article in 2005 it was certainly hinted at by reference to Wikipedia. While there may be a broader overlap between Howe’s description of crowdsourcing and O’Reilly’s description of the Web 2.0, I would argue that crowdsourcing is roughly equivalent to ‘harnessing collective intelligence’  – one of the main characteristics of O’Reilly’s Web 2.0. Arguing for this equivalence can help to better clarify the nature of Web 2.0 and distinguish it from other elements within the Web 2.0 paradigm. Although this may appear to be nothing more than semantics, there is a great potential to influence the developing Web. If theory influences practice then these definitions are not merely a passive play on words but can serve as the dynamic drivers for an evolving paradigm.

Augmented Intelligence

As well as people collaborating through networks there is another possibility. People can be supported by artificial intelligence to augment their decision making. There are various examples of this from trading software through to software which interprets Electrocardiograms. Rather than a collaboration of people analysing data or contributing knowledge, there is the possibility of people interacting with artificial intelligence solutions to look at complex datasets and then contribute to a collective work.

Artificial Intelligence

Artificial intelligence solutions including Expert Systems, Genetic Algorithms and Neural Networks approximate characteristics of human intelligence and biological systems including reasoning, adaptation and learning. The use of artificial intelligence to contribute to the solution of a group problem would add an interesting dimension to the paradigm. Using the web as platform, software can run continuously and respond to new data in real time. However the use of artificial intelligence would require a clear understanding of the goals of the collective project. SETI is an example of software that makes use of hardware to solve a common problem without the need for human intervention other than to provide the distributed processing platform needed for completion of the project.

Conclusions

There are many approaches to harnessing collective intelligence and many of these approaches would have been present in the original conception of the Web. Nevertheless the Web has evolved and collaboration both supported and unsupported by artificial intelligence solutions has resulted in new products and services that have transformed the way people perceive and use the Web. The infrastructure of the Web can be further refined by these approaches and it is important to recognise that the Web is continuously developing. This has implications for every area of our life but also the way in which science is conducted.  The emerging Science 4.0 movement is still defining its identity but many of the approaches above have found application in fields as diverse as Astronomy and the study of Alzheimer’s Disease.

References

Crowdsourcing. Why the Power of the Crowd is Driving the Future of Business. Jeff Howe. 2008. Crown Business.

Appendix

Doing Science 4.0. Deconstructing the Web 2.0. The Web as Platform.

Doing Science 4.0. Part 1. What is Science 4.0?

Doing Science 4.0. Web 2.0

An index of the site can be found here. The page contains links to all of the articles in the blog in chronological order. Twitter: You can follow ‘The Amazing World of Psychiatry’ Twitter by clicking on this link. Podcast: You can listen to this post on Odiogo by clicking on this link (there may be a small delay between publishing of the blog article and the availability of the podcast). It is available for a limited period. TAWOP Channel: You can follow the TAWOP Channel on YouTube by clicking on this link. Responses: If you have any comments, you can leave them below or alternatively e-mail justinmarley17@yahoo.co.uk. Disclaimer: The comments made here represent the opinions of the author and do not represent the profession or any body/organisation. The comments made here are not meant as a source of medical advice and those seeking medical advice are advised to consult with their own doctor. The author is not responsible for the contents of any external sites that are linked to in this blog.

Brodmann Area 22: A Brief Review of the Literature: Part 1

Brodmann Area 22, Derived from Gray’s Anatomy 20th Edition 1918 Lithograph Reproduction, Public Domain

 

BA22 is the Superior Temporal Cortex also referred to as part of the Auditory Association Cortex. In this review, the PubMed interface for Medline was searched using the term ‘Brodmann Area 21′ (without parentheses). Articles of relevance to the search were retrieved and included in the brief literature review below. This is broadly divided into physiological and pathological studies.

In an fMRI study, the researchers found that stimulation of the right ear resulted in bilateral activation in BA22 in 15 subjects with intact hearing. The researchers propose that BA22 is amongst the areas that responds to changes in the middle ear and that BA22 may also be involved in a hypothetical reflex which facilitates speech. Linguistic inference recruited BA22 in this fMRI study which was not the case for logical inference. Stimulation of BA22 with repetitive Transcranial Magnetic Stimulation was associated with a reduction in the loudness of Tinnitus in this study.

In a post-mortem study of people diagnosed with Schizophrenia compared to a control group, researchers looked at the expression of genes in Brodmann Areas 22 and 10 n the two groups. Approximately twice as many of the disease associated transcription factors were age associated in BA10 compared to BA22. The researchers characterised further differences between the two areas. In a post-mortem study of people diagnosed with Alzheimer’s Disease or Schizophrenia, researchers found that there was a similarly high dysregulation of expression of genes in BA22 compared to a control group leading the researchers to suggest a common pathology to the two illnesses in BA22.Reduction in grey matter volume was identified in BA22 in people with Bipolar Disease or Schizophrenia in this structural MRI study. Grey matter reduction in BA22 differentiated people with schizophrenia with predominantly negative symptoms from those with schizophrenia without in this structural MRI study. Grey matter volume was greater in older adults with Schizophrenia than in a group of people with Alzheimer’s Disease but less than an older adult control group in this structural MRI study. However the researchers found that BA22 was one of the areas in which the grey matter volume in the older adults with Schizophrenia and people with Alzheimer’s Disease was similar.  The right BA22 was one of the areas with reduced perfusion in people with Cerebral Amyloid Angiopathy (CAA) (which predisposes to intracerebral haemmorhage) in this SPECT study comparing people with CAA with a control group. In a study comparing people with traumatic brain injury with a control group the researchers found that the latter group were more likely to activate BA22 during a cognitive test – the Paced Auditory Serial Addition Tests (PASAT) which is effective in picking up subtle cognitive difficulties.

An index of the site can be found here. The page contains links to all of the articles in the blog in chronological order. Twitter: You can follow ‘The Amazing World of Psychiatry’ Twitter by clicking on this link. Podcast: You can listen to this post on Odiogo by clicking on this link (there may be a small delay between publishing of the blog article and the availability of the podcast). It is available for a limited period. TAWOP Channel: You can follow the TAWOP Channel on YouTube by clicking on this link. Responses: If you have any comments, you can leave them below or alternatively e-mail justinmarley17@yahoo.co.uk. Disclaimer: The comments made here represent the opinions of the author and do not represent the profession or any body/organisation. The comments made here are not meant as a source of medical advice and those seeking medical advice are advised to consult with their own doctor. The author is not responsible for the contents of any external sites that are linked to in this blog.

News Round-Up 2012 3rd Edition

This edition of the News Roundup is in Video Format Above

There is an interesting write-up on two studies finding that Schizophrenia can be related to Circadian rhythms (via @Maria Page). In the first study from the British Journal of Psychiatry, the researchers found that there was a disruption in sleep in people with Schizophrenia that was independent of the effects of medication being taken to treat the illness. These included phase-changes in the circadian rhythm. In the second study, the researchers investigated the function of the SNAP 25 gene in a murine model. The SNAP-25 protein is a component of the SNARE complex which mediates the release of the contents of intracellular vesicles (vesicles can act as storage structures within the cell). For instance, these could be the neurotransmitters that are released by a neuron.

Snare Complex, Danko Dimchev Georgiev (M.D), Wikimedia Commons, Creative Commons 3.0 License

When the SNAP 25 gene was not expressed, the researchers found that the circadian rhythm was altered. The Suprachiasmatic Nucleus is an important structure in the brain that regulates circadian rhythms – effectively it acts as a clock.

The Suprachiasmatic Nucleus, Justin Marley, Creative Commons License 2.0

The researchers found that although the Suprachiasmatic Nucleus (SCN) was functioning there was a disruption of the signals between the SCN and other organs. They suggest that with sleep disturbances occurring in many mental illnesses alterations in the SCN’s signals should be investigated further and may offer novel lines of inquiry for therapeutics.

In a study of 3, 725 same-sex twins, researchers found that the risk of autism in one twin was significantly correlated with lower birth weight. The researchers were using a cut-off limit of a 15% difference in birth-weight between twins. They found that lower birth-weight was associated with a 13% increase in the risk of Autistic Spectrum Disorder for every 100g reduction in birth weight. However the research also shows that other factors are likely to be important as well.

There is a video here about the experiences of a caregiver for a parent with Dementia.

Psychiatry 2.0

Researchers have identified a correlation between the citation rate for a sample of Science and Nature articles and their citation count on Google Scholar and the Web of Science. However the researchers note it is a correlation and causality would need to be investigated further. The Department of Health has stated a commitment to the 3 Million Lives project which aims to improve the lives of 3 million people over the next five years through Telehealth and Telecare. There’s a very interesting write-up by Thomas Lin in the New York Times on the Open Science movement that is taking pace and Lin takes a look at ResearchGate an online portal that is bringing scientists together.

 

An index of the site can be found here. The page contains links to all of the articles in the blog in chronological order. Twitter: You can follow ‘The Amazing World of Psychiatry’ Twitter by clicking on this link. Podcast: You can listen to this post on Odiogo by clicking on this link (there may be a small delay between publishing of the blog article and the availability of the podcast). It is available for a limited period. TAWOP Channel: You can follow the TAWOP Channel on YouTube by clicking on this link. Responses: If you have any comments, you can leave them below or alternatively e-mail justinmarley17@yahoo.co.uk. Disclaimer: The comments made here represent the opinions of the author and do not represent the profession or any body/organisation. The comments made here are not meant as a source of medical advice and those seeking medical advice are advised to consult with their own doctor. The author is not responsible for the contents of any external sites that are linked to in this blog.

Detecting Movement in the Arms: A Tenuous Link with Emotions

As unlikely as it might sound, there thought to be a tenuous link between detection of movement and emotions. The James-Lange theory of emotions states that emotions result from physiological responses of the body to the environment. The diametrically opposite theory is the Cannon-Bard theory of emotions which states that physiological responses in the body occur subsequent to emotional experiences. The Williams-Lange theory has been refined by A Craig (see here, here and here). In Craig’s model our sense of our own body – interoception – is an important part of emotional experience and he suggests that emotions and interoceptive information are integrated in the Insular Cortex. The model is elaborated on and it is well worth reading Craig’s original works.

So detecting movements in our arms – a type of interoception might be an important component of our emotional experience. However it’s not too far-fetched when you think of the fight-or-flight response. With a lion fast approaching, the sensation of rapid movement in your arms and legs as you exit the scene complements the ‘there’s a Lion right behind me’ thought and the associated anxiety you are experiencing. So now we get onto the slightly more technical bit. How do we detect movements in our body. Well the answer is through mechanoreceptors. These are receptors in the body which are deformed in response to various changes in the body including movements.

So if we want to understand what’s going on as we’re running away from the Lion, part of the picture is provided by considering the movements of our arms. It turns out that our arms are covered in these tiny mechanoreceptors and in this post I am looking at a special type of receptor known as the Ruffini end-organ or Ruffini receptor.

Since they are so tiny, they are usually visualised with a microscope or with special types of staining. In anatomical studies, specimens are obtained post-mortem, prepared using special techniques and then examined using microscopy. It turns out from a review of the literature that this very specialised area of research consists of a very small number of studies which show that the Ruffini endings are found throughout the arm.

Glenohumeral Joint, Gray’s Anatomy, 1918, 20th Edition, Public Domain, Wikimedia Commons

Ruffini end organs were identified in the Inferior, Middle, Superior and Posterior Glenohumeral Ligaments in this study (Vangsness et al, 1995). Ruffini endings were not found in the Glenoid Labrum and the researchers didn’t report the identification of Ruffini endings in the Subacromial Bursa. The researchers suggest that removal of an inflamed bursa may also reduce pain signals from this part of the shoulder.

Flexor Tendons of the Hand, Gray’s Anatomy, 1918, 20th Edition, Public Domain, Wikimedia Commons

In a histological study, flexor tendons of the hand were examined (Zimny et al, 1989). The researchers identified Ruffini endings but these were outnumbered by Pacinian corpuscles and Golgi Tendon organs.

In an immunohistological study researchers examined the index finger of donors and were able to identify only a single Ruffini corpuscle (Paré et al, 2003). They concluded that human glabrous skin was not well supplied with Ruffini endings. In another study, the researchers examined 10 hands using immunofluorescence techniques and looked at the thumb ligaments – the Dorsal, Posterior and Anterior Oblique, Central, Carpometacarpal and Ulnar Collateral Ligaments (Lee et al, 2011). They found evidence of Ruffini endings in the ligaments.

Volar Aspect of Interphalangeal Joints of the Finger, Gray’s Anatomy, 20th Edition, 1918, Public Domain, Wikimedia Commons

The researchers in this immunohistochemical study examined 12 right index finger distal interphalangeal joints and surrounding structures (Chikenji et al, 2011). The specimens were divided into three regions longitudinally these being proximal, middle and distal and these areas were further subdivided. Although other types of endings were more prevalent – the researchers identified type I endings which includes Ruffini Endings. The same research team also studied the 12 right index finger proximal interphalangeal joints and surrounding structures (Chikenji et al, 2010). The specimens were again divided into three regions longitudinally (proximal, middle and distal) and these areas were further subdivided. The researchers found that type I endings (e.g Ruffini-like endings) were more prevalent in the volar plate of the proximal interphalangeal joints.

References

Chikenji T, Suzuki D, Fujimiya M, Moriya T, Tsubota S. Distribution of nerve endings in the human proximal interphalangeal joint and surrounding structures. J Hand Surg Am. 2010 Aug;35(8):1286-93. Epub 2010 Jul 13.

Chikenji T, Berger RA, Fujimiya M, Suzuki D, Tsubota S, An KN. Distribution of nerve endings in human distal interphalangeal joint and surrounding structures. J Hand Surg Am. 2011 Mar;36(3):406-12.

Lee J, Ladd A, Hagert E. Immunofluorescent Triple-Staining Technique to Identify Sensory Nerve Endings in Human Thumb Ligaments. Cells Tissues Organs. 2011 Aug 10.

Paré M, Behets C, Cornu O. Paucity of presumptive ruffini corpuscles in the index finger pad of humans. J Comp Neurol. 2003 Feb 10;456(3):260-6.

Vangsness CT Jr, Ennis M, Taylor JG, Atkinson R. Neural anatomy of the glenohumeral ligaments, labrum, and subacromial bursa. Arthroscopy. 1995 Apr;11(2):180-4.

Zimny ML, DePaolo C, Dabezies E.Mechano-receptors in the flexor tendons of the hand. J Hand Surg Br. 1989 May;14(2):229-31.

Appendix

New video on Ruffini Endings

What does the Insular Cortex Do Again?

Insular Cortex Infarction in Acute Middle Cerebral Artery Territory Stroke

The Insular Cortex and Neuropsychiatric Disorders

Developing a Model of the Insular Cortex and Emotional Regulation Part 1 Developing a Model of the Insular Cortex: A Recap

The Relationship of Blood Pressure to Subcortical Lesions

Pathobiology of Visceral Pain

Interoception and the Insular Cortex

A Case of Neurogenic T-Wave Inversion

Video Presentations on a Model of the Insular Cortex

MR Visualisations of the Insula

The Subjective Experience of Pain*

How Do You Feel? Interoception: The Sense of the Physiological Condition of the Body

How Do You Feel – Now? The Anterior Insula and Human Awareness

Role of the Insular Cortex in the Modulation of Pain

The Insular Cortex and Frontotemporal Dementia

A Case of Infarct Connecting the Insular Cortex and the Heart

The Insular Cortex: Part of the Brain that Connects Smell and Taste?

Stuttered Swallowing and the Insular Cortex

YouTubing the Insular Cortex

An index of the site can be found here. The page contains links to all of the articles in the blog in chronological order. Twitter: You can follow ‘The Amazing World of Psychiatry’ Twitter by clicking on this link. Podcast: You can listen to this post on Odiogo by clicking on this link (there may be a small delay between publishing of the blog article and the availability of the podcast). It is available for a limited period. TAWOP Channel: You can follow the TAWOP Channel on YouTube by clicking on this link. Responses: If you have any comments, you can leave them below or alternatively e-mail justinmarley17@yahoo.co.uk. Disclaimer: The comments made here represent the opinions of the author and do not represent the profession or any body/organisation. The comments made here are not meant as a source of medical advice and those seeking medical advice are advised to consult with their own doctor. The author is not responsible for the contents of any external sites that are linked to in this blog.