I’d get pretty bored if no one wanted to bother me with any questions - I do have to pass my day somehow
The frontal lobe is important for loads of things including movement, sensation, decision making, personality, working memory, personality and controlling inappropriate behaviour. The superior part of the lobe, ie the upper part, suggests that it might be somewhere in or near the motor area, but that is a complete guess and I could easily be wrong! If it was there though, it would mean that the left side of your body would be affected in some way.
The corpus callosum is the main tract of white matter joining the left and right sides of the brain. It is a very common place for MS to attack. It consists of fibres that link bits of the brain that need to work together. For example, if you use two hands to reach for something, the left side of the brain is directing your right hand & arm and the right side of the brain is directing your left hand & arm and to work together to do it properly, the two sides need to “talk”. So, from birth, every time someone reaches with both hands, connections between the areas involved develop and strengthen so they work effortlessly. Those connections (and others like them) form the corpus callosum. Because it deals with making left and right work together, damage there can affect all sorts of things, e.g. reaching with both hands, being able to tell the direction of sounds or which side of your body you have more pressure or sensation on, eye movements and cognitive tasks. The cognitive stuff can be fascinating: some things are processed in only one side of the brain so when the corpus callosum is cut completely you can end up with someone who can’t tell you what a simple word is if they can only see it with the left eye, but they can still copy it / write it, and then when you switch the picture to the right eye, they can tell you what it is, but they can’t copy it any more!
Please note that MS does not tend to cause this level of damage to the corpus callosum; I’m talking mainly here about patients that have had it done surgically to stop terrible epilepsy (google “split brain patients”).
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