Wednesday, September 30, 2015

Suffer not

I am arguing that I did not differentiate the left and right half of other people's faces as I grew up and that it was reflected in how I used myself. I saw the right side as the persona of others and I am in my movement picture right sided. A recent article on a popular science site talks about the connection of seeing and feeling pain and empathy to the other person. It does not specify any differences in the sides of the person but links the seeing and empathy.

If there is pseudoneglect of the left side of the other person's face would I have decreased developmental control of my own?  I feel in the own use of the left side of my face is largely the inability to relax what I already do.

Revising the brain

In an older post I linked a story and a video about a girl with half a brain. If she is controlling both sides with the one hemisphere it gives weight to the theory of one sided control theorized here.  I'am kind of sad that the video is gone but from what I remembered the girl displayed more normal movement on one side.  There seemed to be to be an excitatory control of the impaired side but not one where I got the sense where she could relax the muscles to make it more efficient.  There is also definite timing element that could be controlled from the one side.  I was wondering if she had to use an orthotic for the impaired lower extremity ankle control or had surgery to fuse the ankle. There are several cases with one cerebral hemisphere mostly destroyed seen fairly regularly in the news. The concluding remark is usually by a doctor/neurologist that says something like "we will have to revise our current understanding of the brain"

Makes me wonder if the lesion seen here could be thought of as an excitatory impairment only. In a sense that there is no off switch. Normally the right hemisphere would be able to control the left side ability to relax but is overwhelmed by the always on signal from the dominant side.

Half a link

  • Doctor: Lesion "basically took away the left side" of Michelle Mack's brain 
  • Right side of her brain essentially rewired itself to take over left-side functions 
  • She lost some language ability, emotional control because of the rewiring
  • Mack's message to the world: "I'm normal but have special needs" 

Tuesday, September 22, 2015

Pseudoneglect and differentiating the left half of face

I am of the belief I never really saw the left half of people's faces. The term for this is called pseudoneglect and it is common for a right hander to pay more attention to the left half of his her visual field. (which would be the right side of someone else's face)  There are many studies showing that seeing and mimicking of others face's recreates the emotions and muscular actions in ourselves. I believe the seeing of the left half of other people's face now and the persona reflected in it allows for a greater differentiation of what I do with my left and right half of face.

If I am correct the the lateralization of the brain for speech and right handedness lies in the lack of differentiation of both perceiving others and myself. It still remains the great possibility that there are both structural and developmental aspects of the nervous system that starts and kept me on the path of not perceiving the differences.

Pseudoneglect link

Faces and emotion

Thursday, September 17, 2015

A sprain a day

I played many sandlot sports growing up as a kid. There was a period where it felt like I was spraining my ankles daily. The NY Times has an article that I found interesting as to the functional cost of this minor injury. The soccer team at my college had several players that had to bandage their ankles almost into a cast to keep playing.  On a subconscious level I feel I adapted strategies to keep playing without re turning my ankle. Some of the brilliance in the work of Moshe Feldenkrais I felt was to allow safe play in many of the actions that I long forgotten or never knew.

In the extreme I often saw in the nursing homes patients who became a fall risk were then limited to the bed and wheelchair. He or she would only be allowed to transfer and walk with someone assisting. It could go rapidly downhill from there as then the patient became fearful of trying to walk and then later any mobilizing.  A 90 year old 90 pounder might be the most difficult transfer in the world if they extended backward to stay in the wheelchair at the pelvis and having a death grip on anything stable in the vicinity. Many times just rolling side to side in bed would provoke the fear response of falling and the patient would resist simply resting on either side to be changed. Nurses and staff frequently hurt their own backs helping these patients.

Occasionally I had some limited success working on the mat and having the patients coaxed gently to their stomachs. Having the orientation with the face down and trunk supported with pillows relaxed them in with the fear of falling while rolling. A patient who could not sit independently at the edge of mat because they extended backward would then would be able to sit normally without assistance. Almost all the time the improvements would be temporary as the next day the process would need to be repeated. As soon as the patient's therapy came to the end because of insurance any residual change would be lost rapidly.

Similarly with spinal cord patients their transfers would often improve after getting them prone. As most had lost control of the trunk musculature coming forward to allow for an easier transfer was scary. They needed to sense that the change in orientation could be safe  before they could allow themselves the greater control the arms and shoulders required for the loss of the trunk. It seemed cruel at times to put someone prone and have them attempt modified pushups but it was very functional in a not very apparent way to the patient. The main difference is once the patient understood the improvement they kept the functionally as compared to the nursing home patient.

To tie this in with my blog theme with most of my own patterns of movement reside in the varied subconscious decisions that either felt safer or more functional. If any approached a conscious level they were then soon forgotten after habitualization.  These preference define my posture and actions.

Friday, September 11, 2015

I'm so excited

If I only see the persona exhibited in the right half of face is that what is excited in me? I am presuming my left hemisphere

Just a link

The perception of action is associated with increased activity in motor regions, implicating such regions in the recognition, understanding and imitation of actions. We examined the possibility that perception of speech, both auditory and visual, would also result in changes in the excitability of the motor system underlying speech production. Transcranial magnetic stimulation was applied to the face area of primary motor cortex to elicit motor-evoked potentials in the lip muscles. The size of the motor-evoked potentials was compared under the following conditions: listening to speech, listening to non-verbal sounds, viewing speech-related lip movements, and viewing eye and brow movements. Compared to control conditions, listening to and viewing speech enhanced the size of the motor-evoked potential. This effect was only seen in response to stimulation of the left hemisphere; stimulation of the right hemisphere produced no changes in motor-evoked potentials in any of the conditions. In a control experiment, the size of the motor-evoked potentials elicited in the muscles of the right hand did not differ among conditions, suggesting that speech-related changes in excitability are specific to the lip muscles. These results provide evidence that both auditory and visual speech perception facilitate the excitability of the motor system involved in speech production.

I'm so excited

Why are there more blind left handers?

ABSTRACT Rates of left-handedness were compared in 1387 blind and 831 sighted children. The rate in male blind children was higher than in female blind children. The incidence of left-handedness was significantly higher in blind than in sighted children in both boys and girls. The percentages of left-handedness were 18.23% and 17.02% in male and female blind children, and 11.02% and 7.52% in male and female sighted children, respectively. It can be stated that sighting is important in the development of normal typical cerebral lateralisation or hand preference.
Left-handedness in blind and sighted children - ResearchGate. Available from: [accessed Sep 11, 2015].

Tuesday, September 8, 2015


In the video by Dr. Derakhshan from his very interesting site  Mimicking Man  there is a demonstration of a patient with spasticity to the left arm with ipsilateral left hemisphere lesions. If we are wired simply as the right hemisphere controls only the left side of the body then and the left hemisphere controls only the right then there should not spasticity on the same side. His theory of the one directionality of the corpus callosum could explain the spasticity in the left if the dominant left hemisphere (my assumption)has a executive command for both and the lesion is in the specific area where it relates to control solely of the left arm. There appears to be some transient improvement in the movement of the left arm after he manipulates the right.

In the work with my left tongue there is and has been a feel that my usual mode of movement is more under control of what I assume to be my left hemisphere. It is commonly accepted the tongue as a whole should be half left and half right corresponding contralaterally.  I have been working on trying to accentuate the ability of my left tongue throat musculature to be more independent which I have been messing around with the last 5 years or so.

The new movements that I am feel are mainly in the sub-lingual region when I try to access my left tongue/throat/face.. The 'left tongue movement is extremely tiny and often I am unclear if I am really moving it. However the sublingual region extending to below the hyoid even though small visibly feels much larger. The left lower face including left lips now are cooperating in a different way when I attempt to talk from the left side. The movements feel somewhat spastic and as if I am pushing through resistance. If I expand the area that I pay attention to, the spine and skull have a different sense of movement and orientation. There is some sense that I have to reorient what the right side musculature does to allow the left to be put in slight position of advantage. In kinesiology we are taught the lengthened position of the muscles are more advantageous than the ones at end range. With many of my right sided movements I feel my left has more of a stabilizing role where the right is given a position where it has relatively more freedom even before the movement is originated.

My gut feel is that my structures close to my midline are somehow more or less directed by the left hemisphere in my older more normal way of moving and still by far the usual if I am not paying attention.  In a study referred by the Doctor it suggests what I found in my own movement. (Evidence for bilateral innervation of certain homologous motoneurone pools in man L. J. Carr, Linda M. Harrison * and J. A. Stephens)

 Some significant quotes the first of which relates to the muscles of the more distal arms"This lack of a common drive to these co-contracting muscles is presumably commensurate with the independent control of the two arms by the central nervous system." and the following opposite behavior by the muscles closer to the midline "Cross-correlation analysis suggests that the left and right diaphragm, rectus abdominis and masseter muscles each share a common drive. As argued above, this drive probably comprises activity in last-order branched fibres and presynaptic synchronization. Focal magnetic stimulation of the motor cortex produced bilateral responses in these homologous muscle pairs. For the rectus abdominis and masseter muscle pairs, the latencies and sizes of these ipsilateral and contralateral responses were not significantly different. Taken together with the results of the cross-correlation analysis for these two muscle pairs, the results suggest that corticospinal fibres may provide the common drive to the left and right motoneurone pools. This common drive may arise from activity in corticospinal fibres that branch and supply the left and right motoneurone pools and from activity in corticospinal tract cells whose activity is synchronized at the cortical level."  Much in the study is far above what I currently understand.

I have referred to the pelvic clock exercise by Moshe Feldenkrais before where over time and slow movements I learned the left lower quadrant of my stomach muscles never relaxed during the exercise until I learned how. If one lays on one's back and pretend one is laying on a clock with the center of the face under the middle of the sacrum one rolls the sacrum up to 12:00 and down to 6:00. The outside left in the middle is 3:00 and 9:00 is the outside right. To make the movement the more easier and pleasurable I had to come to the realization that I never relaxed the muscles of left lower quadrant musculature as the right upper contracted. In a sense fighting myself in doing the circle of the left lower quadrant. I could do the movement but with a sense of irritation and being rushed. Bringing that sense to the throat region,  I could not separate in my mind what the left tongue/sub-lingual/face musculature does compared to the right. When I sense the the throat, tongue musculature I get a feel it is the most known but least accessible to differentiate in terms of movement. What is suggested by the Dr. Derakshan is that the control of the non dominant hemisphere from the dominant is always excitatory never inhibitive(relaxative).

However something as distal as my left hand should independent according to my model and from my understanding of the above study that he references in his article. There may be an executive timing motor planning issue directed from the left hemisphere that I can not rule out or feel, but the spasticity in the hand in the Dr's video suggest far more than that to me.

How can I  can account for the difference? There is a theory about Kernohan's notch which the Doctor is well aware of and discounts.  So there is a disconnect between what he is saying and I am feeling but there is also a large overlap as well. I can not account for the discrepancy in timing of attempted simultaneously movements. His idea the role of the non-dominant eye expanding the field of the dominant but not consciously seeing  also corresponds to what I sense, but I do not think it is fixed in stone  His study is scientifically based although not well accepted as far as I know. Mine is neither.

Saturday, September 5, 2015

Split Pitt

Small post from this site. It shows Brad Pitt making large moves to the left and right that demonstrates the additional time that he uses to move to the nondominant side and the delay that happens as the signal is having to travel through the corpus callosum has to travel the further difference to the non dominant side.

However how about this gal?  I assume she is using each hemisphere in their own direct path. In playing the violin or other complex activities the dominant side may be the executor of the timing but there would seem to me the independence of the complex movements for each.

A different link from the site I found the following quote, " On the other hand, we have no choice as to the hemisphere with which we speak."  It is a very interesting read for me as it aptly demonstrates the discrepancy that I am finding in my left and right side. However it would lead to the conclusion that it is impossible to talk with the left tongue. My belief is that is the the usual but not always the possible. What is lacking in my opinion is the ability to differentiate between the left and right structures because of the complexities of the actions as most of the neural development happens prior to the awareness needed to examine such activity.

Thursday, September 3, 2015

Separate but unequal

I have been thinking which is always dangerous when one has a limited capacity to do so, but I still have plenty of discrepancies in my thoughts about the left tongue. If I am correct that the left tongue/sublingual/face/eye exists in a separate but accessible mode from my usual right dominant side then the explanation of why I had no knowledge of it until after I started looking for it is still lacking. Some options might be

  • I am wrong
  • The right side inhibits perception of the possibility of left side dominance
  • There is cooperation between the right and left to achieve one functional outcome.
  • The left side never developed
  • I am a creature of habit
  • Structures of the brain are organized to lead to one side dominance
  • It is simply a lack of being able to differentiate between the left and right

I don't think it is possible for me to come to any conclusions on which is more correct after I throw out the first option. In fact I don't think I will be able to resolve anything with the resources I have. However I can continue to play with trying to enhance the separate but unequal left side use of myself.

late edit  Just reading this study where the author suggests that there is a one way directional transfer of information form the corpus callosum from dominant to non dominant side. A couple of interesting quote

Similarly, when viewing a target in the middle of our view, vast majority of right handed people will initiate a search to the left of the midline, focusing slightly to the left of the middle of a word target, ... The twin phenomena mentioned above are based on the fact that the interhemispheric traffic, underpinning laterality of motor control, is one‐way (from the major to the minor hemisphere, as here defined)and that the nature of signals employed for the purpose of activating the nondominant side is purely excitatory

Link to site