Well it is just over 4 months since I initially submitted my Research Project proposal which seems ages ago. It’s 6 weeks since I resubmitted it, hopefully having addressed their conditions and I am chasing things as well now as I am less convinced about the rigour of their processes. ‘Turnitin’ seems to be a black hole that just checks how much of your work is copied from others. I love it when it picks out a phrase like “reaching their potential” and then cites it in some random person’s website. This means that you have to go through and see how much of the 18% ‘copied’ words you need to worry about. On the upside, it has meant that since mid-July I have been able to focus on the bit I love, the neuroscience, rather than writing academic stuff.
I am another 100 pages through the text book and it is fascinating. I have learned about how neurons (probably) grow towards where they need to go as well as learning about all the sensory systems. I am glad I have an electrical engineering degree as I can understand the electrical circuits used within neural firing and their oscillations. Although I never thought I’d have to brush up on this through being a coach.
I like the little side bits I am discovering such as chillies are ‘hot’ because they activate the same receptors as ‘bad heat’ (>43 degrees) which means we quickly do something about it and don’t eat too much. I am assuming this is because in large amounts those chemicals are unhealthy for us. Likewise, menthol activates the cool temperature receptor so it corresponds to our ‘cool’ sensation. I suppose the larger debate is around what do we define as ‘hot’ and ‘cold’ as they are human interpretations. Although very hot and very cold both feel like a ‘burning’ sensation which is probably our word for the ‘my cells are being destroyed’ feeling which is what it comes down to.
In reading about the senses, I get a picture of how each one is so well tuned for the particular aspect that it needs to be alerted to in order for us to survive. So, for vision there are a lot of neural networks to do with edges as these help with movement and speed of movement. Also edges help us see predators hiding. Then there is colour which helps us see what is ok to eat and what is not, as well as predators hiding. It has made me wonder whether very tidy people who are nervous are tidy as it reduces edges and makes the edges aligned. Both of these would make it easier to see threats. Although they are not consciously doing it for those reasons I wonder if that is the underlying survival rationale.
Strengthening the ‘reasoning’ ability of the neural system feels like a useful thing do as it helps the brain to control emotional reactions before they get out of control. Also, I wonder how much more we’d get done at work if there was less fear and anxiety around. Maybe in 100 years that will be the role of a leader or HR.
With sight and sound, spatial maps are recreated in the brain. Visually there appears to be a mapping of retinal receptors to the same layout in the brain. This means neurons from the retina must end up in the same order in the visual cortex and it is amazing how it is thought that they do this. In many ways, it is very simple as they use a lot of chemical repulsion and attraction although given the number of neurons this means that the difference in that is quite subtle.
For example (in a simplistic way), if you had 100 neurons from the left to right side of the retina and the one at the furthest left had the most of Chem A, say 100%. Then the one furthest to the right would have the least amount, say 1%. Each neuron in between from left to right would go from 99% to 2% in a downwards gradient. The neurons they need to connect to, further along pathway towards the brain, also go from left to right but have Chem B with a 1% to 100% upwards gradient from left to right (the opposite way around). If Chem A and B repel each other, then the one with most Chem A (furthest left) will end up connected to the one with least Chem B (furthest left) and so forth. Thus, the neurons connect left to right as they were in the retina, maintaining the spatial representation.
Smell is different. In a frog experiment it appears that a coding system is used. Each odour has a unique neural firing pattern using the same set of neurons (which neuron and with what level of activation). Therefore, you can detect many different smells using fewer neurons and, for odour, a map is less useful than being able to detect lots and lots of different smells. So the brain has to decide how best to use its finite resources and each system seems very well honed to its work.
The ears turn sound waves into movement by using lots of little hairs inside them. The hairs are different heights, like pan pipes, and at the top of each hair is a ‘lidded’ opening. The ‘lid’ has a ‘string’ connected to the taller hair behind it. When sound moves the hairs, the tops of them move further apart thus the ‘string’ pulls the ‘lid’ open and ions enter to enable depolarisation. Movement using the ear canals, is similar although fluid and calcium granules create the hair movement. Should I be amazed or concerned as it’s a bit like a team building exercise solution but without bake bean tins.
Next time I’ll talk about neural oscillations and complex systems as these also seem relevant to ‘the self’ conversation and my DProf.