Monthly Archives: April 2013

Intermezzo: A Visual Illusion Experiment – Part 11

ContrastIllusionPerspectiveIntermezzo, Public Domain

Continuing with the contrast illusion theme (see Appendix) I created the above picture to illustrate the theme.  Thus although all of the filled circles are of the same colour, this colour appears different in the context of the background. Quite accidentally there is a further illusion in the picture. The right side may appear wider than the left side. This is because the theme involves a depth perspective. The images on the left appear closer than those on the right and this interferes with the assessment of the width of the image.

Appendix

Explaining the Neurobiology of Illusions – A Talk from Caltech

Do Cats See Illusions Too?

A Visual Illusion Experiment – Part 10

A Visual Illusion Experiment – Part 9

A Visual Illusion Experiment – Part 8

A Visual Illusion Experiment – Part 7

A Visual Illusion Experiment – Part 6

A Visual Illusion Experiment – Part 5

A Visual Illusion Experiment – Part 4

A Visual Illusion Experiment – Part 3

A Visual Illusion Experiment – Part 2

A Visual Illusion Experiment – Part 1

Index: There are indices for the TAWOP site here and here 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.

Are GABA Receptors Related To Anxiety in Humans Because Worms Wriggle? Building a Model of the Insular Cortex – Part 14

Slide2

In the previous post I looked at GABA receptors in C.Elegans – the Nematode worm. C.Elegans has been extensively studied and there is a very sophisticated understanding of the organism’s biological machinery. What I found fascinating was that the role of the GABA receptors in C.Elegans has been clarified and has been found to play a role in movement as well as a few other functions. There are only 26 neurons in C.Elegans.

C.Elegans

The Nematode worm moves by contracting the muscles on one side of its body whilst relaxing the opposing muscles. The GABA receptors are involved in the relaxation of the muscles.

Muscle Relaxation and GABA Receptors

When people are anxious this can cause the muscles to tense. Some drugs acting at the GABA receptors in humans can reduce muscle tone. Some drugs which target these receptors can also alleviate anxiety. Which comes first? This is the chicken and egg scenario. Do you have to be anxious to have tense muscles or do you become anxious because your muscles are tense.

The James-Lange and Cannon-Bard Theories

The question of whether emotions or bodily sensations happen first is dealt with by the James-Lange and Cannon-Bard Theories. Essentially the two theories take differing positions on the question. The James-Lange theory states that emotions happen in response to information coming from the body. When the heart races you feel anxious. The Cannon-Bard theory says that  emotions and bodily responses occur independently but can be coordinated by the Thalamus.

Nematode Worms, GABA Receptors and Anxiety in Humans

Nematode worms and our ancestors diverged some 800 million years ago. In that space of time Nematodes and our species have continued to evolve. Nevertheless the conservation of the GABA receptors in both Nematodes and our species is evidence of the importance of these receptors. Some simple connections and a narrative can be constructed to account for the above.

1. Nematodes have developed GABA receptors to facilitate movement

2. GABA receptors enable Nematodes to relax muscles to steer and move in certain directions

3. GABA receptors are part of a movement apparatus

4. As species have evolved and become more complex they have become capable of conscious experience

5. The movement apparatus has been conserved but also become associated with other complex phenomenon such as conscious experience

6. In humans muscle groups oppose each other – reciprocal extensor and flexor muscle groups at the elbow are one example.

7. The underlying relationship with GABA receptors remains

8. Action through the GABA receptors relaxes muscle groups and results in accompanying sensory feedback (small variation in the GABA receptor gene may not be related to anxiety but rather it is the physiological effects that the products of these receptor gene variants have in common).

9. This sensory feedback produces an emotional response – lowering of anxiety

While the above supports the James-Lange theory we could argue that there is a bidirectional relationship. For instance a heightened state of anxiety in response to internal stimuli can increase the tension in the muscle groups.

The above is a testable hypothesis. The hypothesis makes a very specific statement about a receptor in adaptive terms. The GABA receptor facilitates movement of the organism. Whilst it may well be wrong it nevertheless contains implicit assumptions which make it testable against the evidence base. The theory in essence states that the GABA receptor function is conserved and associated with increasingly complex phenomenon. If on moving from Nematode worms to humans there was convincing evidence of loss of motor related GABA receptor function in intermediary species this would contradict the hypothesis.

 

References

Jorgensen, E.M. GABA (August 31, 2005), WormBook, ed. The C. elegans Research Community, WormBook, doi/10.1895/wormbook.1.14.1, http://www. wormbook.org.

Related Resources on this Site

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

Building a Model of the Insular Cortex – Part 2: Reviewing a Model by Craig – Part 1

Building a Model of the Insular Cortex – Part 3: Reviewing a Model by Craig – Part 2

Building a Model of the Insular Cortex – Part 4: Reviewing a Model by Craig – Part 3

Building a Model of the Insular Cortex – Part 5: The Evolution of the Insular Cortex

Building a Model of the Insular Cortex – Part 6: A Recap

Building a Model of the Insular Cortex – Part 7: The James-Lange Theory

Building a Model of the Insular Cortex – Part 8: The Cannon-Bard Thalamic Theory of Emotions

Building a Model of the Insular Cortex – Part 9: Charles Darwin on the Expression of the Emotions

Building a Model of the Insular Cortex – Part 10: The Limbic System

Building a Model of the Insular Cortex – Part 11: A Second Recap

Building a Model of the Insular Cortex – Part 12: GABA receptors and Emotions

Building a Model of the Insular Cortex – Part 13: GABA receptors and Nematode Worms

What does the Insular Cortex Do Again?

Insular Cortex Infarction in Acute Middle Cerebral Artery Territory Stroke

The Insular Cortex and Neuropsychiatric Disorders

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 (Brodmann Areas 13, 14 and 52)

New Version of Video on Insular Cortex Uploaded

Contributors to the Model (links are to the posts in which contributions were made – these links may contain further links directly to the contributors)

Ann Nonimous

The Neurocritic

Psico-logica

Index: There are indices for the TAWOP site here and here 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.

Genes and Mental Illness News Roundup: April 2013 4th Edition

One research group suggests that a protein CD33 may be involved in the development of Late Onset Alzheimer’s Disease through an action on the brain’s support cells – the microglia  . The talk below covers CD33 amongst many other associations with Alzheimer’s Disease.

Alzheimer’s Disease – From Genes to Novel Therapeutics

Researchers compared two measures of non-motor Parkinson’s Disease symptoms – the MDS-UPDRS Part 1 and the Non-Motor Symptoms Scale NMSS. The researchers found that the scales had good convergent validity generally but not in cases where the non-motor symptoms were severe (Martinez-Martin et al, 2013).

The Journal of Molecular Psychiatry recently started up. There is an editorial here.

There is an interesting write-up at the Schizophrenia Research Forum on the psychosis prodrome from the 2013 International Prodromal Research Network Meeting in Florida.

Researchers in one study found evidence that people with Alzheimer’s Disease may experience difficulties in recognising changes in affect in themselves* (Verhülsdonk S et al, 2013).

There is a look at  Tetracyclines and Amyloidosis in this paper (Stoilova et al, 2013).

Researchers in Japan suggest that there may be subtypes of Alzheimer’s Disease determined by comorbidity on the basis of their neuroimaging findings (Fukazawa et al, 2013).

There is a look at the evidence supporting a relationship between Lithium and neuroprotection in this paper (available at Pubmed Central). The authors recommend further long-term studies to further investigate this relationship.

Researchers in this study used a novel approach for assessing medial frontal lobe function – a test of object alternation (Freedman et al, 2013). The researchers found that performance on an object alternation task was correlated with medial frontal lobe grey matter volume in people with Frontotemporal Dementia.

The researchers in this study find a possible relationship between bradycardia and Frontotemporal Dementia but recommend further research to confirm this relationship (Robles et al, 2013).

Researchers in this study identified differences in visual motion event related potentials between people with Alzheimer’s Disease and healthy controls (Fernandez et al, 2013).

There is a look at subjective cognitive impairment in this paper which is available at Neurologia (Garcia-Ptacek et al, 2013).

News Roundup Elsewhere

Vaughan Bell interviews psychiatrist Professor Michael Owen about the relationship between genes and mental illness.

Psychiatry 2.0

Psychiatry 2

There is an interesting piece on open access science at Ars Technica.

Neuroscience

brain.1

Kelly Tyrell looks at how science and journalism are coming closer together with the field of data journalism.

Charles Fernyhough looks at neuroscience in fiction in this piece.

New Scientist covers software developed by an Australian group that assesses emotions in photographs in this piece.

References

Fernandez R, Monacelli A, Duffy CJ.J Alzheimers Dis. 2013 Apr 17. [Epub ahead of print] Visual Motion Event Related Potentials Distinguish Aging and Alzheimer’s Disease.

Fukazawa R, Hanyu H, Sato T, Shimizu S, Koyama S, Kanetaka H, Sakurai H, Iwamoto T.Dement Geriatr Cogn Disord. 2013 Apr 13;35(5-6):280-290. [Epub ahead of print] Subgroups of Alzheimer’s Disease Associated with Diabetes Mellitus Based on Brain Imaging.

Garcia-Ptacek S, Eriksdotter M, Jelic V, Porta-Etessam J, Kåreholt I, Manzano Palomo S.Neurologia. 2013 Apr 16. pii: S0213-4853(13)00052-2. doi: 10.1016/j.nrl.2013.02.007. [Epub ahead of print] Subjective cognitive impairment: Towards early identification of Alzheimer disease.

Martinez-Martin P, Chaudhuri KR, Rojo-Abuin JM, Rodriguez-Blazquez C, Alvarez-Sanchez M, Arakaki T, Bergareche-Yarza A, Chade A, Garretto N, Gershanik O, Kurtis MM, Martinez-Castrillo JC, Mendoza-Rodriguez A, Moore HP, Rodriguez-Violante M, Singer C, Tilley BC, Huang J, Stebbins GT, Goetz CG. Eur J Neurol. 2013 Apr 22. doi: 10.1111/ene.12165. [Epub ahead of print] Assessing the non-motor symptoms of Parkinson’s disease: MDS-UPDRS and NMS Scale.

Robles Bayón A, Gude Sampedro F, Torregrosa Quesada JM.Neurologia. 2013 Apr 16. pii: S0213-4853(13)00055-8. doi: 10.1016/j.nrl.2013.02.010. [Epub ahead of print] Bradycardia in frontotemporal dementia.

Stoilova T, Colombo L, Forloni G, Tagliavini F, Salmona M.J Med Chem. 2013 Apr 23. [Epub ahead of print] A New Face for Old Antibiotics: Tetracyclines in Treatment of Amyloidosis.

Verhülsdonk S, Quack R, Höft B, Lange-Asschenfeldt C, Supprian T.Arch Gerontol Geriatr. 2013 Apr 15. pii: S0167-4943(13)00045-9. doi: 10.1016/j.archger.2013.03.012. [Epub ahead of print] Anosognosia and depression in patients with Alzheimer’s dementia.

* This may be related to alexithymia although in this paper the researchers refer to ‘anosognosia for affect’.

Appendix

News Round-Up 2008-2011

News Round-Up 2012

Index: There are indices for the TAWOP site here and here 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.

Cameron Neylon on Open Science

Scientist Cameron Neylon is an advocate for open science and in this video (from the Open Repositories 2012 conference) he talks about many important aspects of open science. Neylon gives examples of scientific communities that have transformed research methodologies through online networks and accelerated analysis of data in the process. He also looks at the issue of increasing the impact of open science through open science networks. There is a question and answer session at the end.

Index: There are indices for the TAWOP site here and here 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.

Revising the Description of Speech with the Three Structure Model. Integration in Neuroscience: A Core Problem – Part 11 (Updated)

IntegrationInNeuroscience

A Three Structure Model of Neural Activity in Relation to Consciousness and Language

In a previous post I suggested how speech might be accounted for by the three structure model. In retrospect I think there is some modification needed and I propose that speech has three components as per the diagram below.

theplaceofspeechinthethreestructuremodel

Speech and the Three Structure Model

Unfortunately it has got a little complicated and the arrows cross each other in the diagram. Nevertheless this reflects the complexity of the interaction between mind and brain. I will explain the three divisions of speech in the three structure model.

With automatic speech, the neural activity takes place in the cranial nerves. At this stage all of the decisions about speech have been made and it has now became a matter of activating the muscle groups in a predetermined manner.

With sensory speech feedback, we become aware of the sound of our own voice as we are speaking as well as the other sensory feedback such as the movement of the jaw and the contact of the tongue with the palate. While it is more likely that this will impact on our consciousness it is also possible for it to act on us unconsciously. For example, if prose is well learnt and it is being repetitively rehearsed it may be possible to divert conscious activity to other matters.

Speech modifiers describes the decisions that are made about how we translate language into speech. Rather than simply speaking our ‘language script’ in a standardised manner, we are able to modify the tone, rate, rhythm and volume of speech. We do this in order to engage with the audience and also to communicate the emotional meaning of our speech. Again this can be conscious or unconscious.

componentsofspeechin3structuremodelRelationship Between the Three Components of Speech

The relationship is shown in the above diagram.

The description of speech in the three structure model can be better understood by considering the video below.

Vocalisation in a Video by Dr J.P.Thomas

In the above video, the singer is demonstrating scales crescendo/decrescendo whilst stroboscopy reveals the corresponding changes in the larynx. The Larynx is a complex piece of anatomical apparatus featuring intrinsic and extrinsic muscles as well as vocal cords. The vocal cords vibrate up to 100 times per second.

As we view the clip the three components of speech are apparent after further reflection (although strictly speaking this is not speech it demonstrates the principles discussed above).

Firstly the automatic component of vocalisation is apparent. If we volitionally attempted to vibrate the vocal cords 100 times per second by focusing on the vocal cords themselves we would no doubt fail. Seeing the vocal cords might give us the opportunity for finer volitional control but it is unlikely given the rate at which they are vibrating with vocalisation. Additionally as we do not see our own vocal cords when we are speaking, our method of organising their movement must be entirely dependent on auditory feedback. We leave the finer details of achieving these movements to our cranial nerves and instead focus our conscious attention on the end result.

This brings us onto the second component of speech which is sensory feedback. The singer demonstrates a crescendo and decrescendo. Although this may be well rehearsed it is most likely that this technique requires close attention to the vocalisations produced up until that point. This feedback can be used to correct any deviation from the anticipated vocalisation.

Finally there is the crescendo and descrescendo. This is analogous to the speech modifiers which communicate the emotional content of our speech.

Speech remains outside of the three structure model. Nevertheless it is sufficiently complex to be usefully described in relation to the three structure model as it provides us with an intuitively understandable phenomenon that can be explained by this relatively abstract model.

Appendix – Related Resources on the TAWOP Site

In Support of Method

A Review of the Structure of Scientific Revolutions

An Interpretation of Scientific Revolutions

Integration in Neuroscience: A Core Problem – Part 1

Integration in Neuroscience: A Core Problem – Part 2

Integration in Neuroscience:A Core Problem – Part 3

Integration in Neuroscience: A Core Problem – Part 4: A Language for Mind and Brain?

Integration in Neuroscience: A Core Problem – Part 5: A Three Structure Model

Integration in Neuroscience: A Core Problem – Part 6: Reflection on the Three Structure Model

Integration in Neuroscience: A Core Problem – Part 7: The Unconscious in the Three Structure Model

Integration in Neuroscience: A Core Problem – Part 8:

Integration in Neuroscience: A Core Problem – Part 9:

Index: There are indices for the TAWOP site here and here 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.

Writing A Paper With A Reference Manager – A Brief Look at Endnote

One of the reference managers on the market is Endnote. In the above video Janine Lim shows us how to complete several useful tasks with Endnote. In previous posts (see Appendix) we looked at another reference manager – Mendeley. There are many other reference managers in addition to these two which will suit a variety of needs.

Appendix – Related Resources on this Site

Working with PubMed – Part 1: Getting started with a shortcut

Working with PubMed – Part 2: Favoriting abstracts

Working with PubMed – Part 3: Bibliography

Working with PubMed – Part 4: Receiving News Updates on PubMed

Working with PubMed – Part 5: Setting Filters

How to receive research paper e-mail alerts

A Video Celebrating 10 years of PubMed Central

How to improve your search results with Medline

Looking at a Reference Manager: A Brief Look at Mendeley

Looking at a Reference Manager: A Brief Look at Mendeley 2

Looking at a Reference Manager: A Brief Look at Mendeley 3

Index: There are indices for the TAWOP site here and here 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.

Contrast Illusions and Geometry: Continuing with a Visual Illusion Experiment – Part 10

multicontrastao

In the last post we looked at the a number of images and altered single characteristics to assess the impact on the contrast illusion. The hypothesis generated was that the letter A when compared to a filled circle could with a graded background produce the illusion of heterogeneity within the same shape (i.e within the letter A). The underlying assumption was that the geometry of the letter A would impact on the perception of contrasting colours in the background and foreground to produce the illusion of variegation. The above diagram was created to test this hypothesis. A cursory examination of the diagram suggests that the hypothesis is incorrect. Nevertheless the more general contrast illusion persists. Both the A’s and the solid filled circles appear lighter on the right than on the left.

Appendix

Explaining the Neurobiology of Illusions – A Talk from Caltech

Do Cats See Illusions Too?

A Visual Illusion Experiment – Part 9

A Visual Illusion Experiment – Part 8

A Visual Illusion Experiment – Part 7

A Visual Illusion Experiment – Part 6

A Visual Illusion Experiment – Part 5

A Visual Illusion Experiment – Part 4

A Visual Illusion Experiment – Part 3

A Visual Illusion Experiment – Part 2

A Visual Illusion Experiment – Part 1

Index: There are indices for the TAWOP site here and here 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.