Proprioception and Vestibular Sense – Other Senses (PSY, BIO)

00:01 Now what are some the other senses that come to forefront? Again, we have a lot of different senses and we highlighted the usual, the usual suspects, but there are a couple other that I wanted to highlight as well. One is kinesthetic sense or proprioception. This is you being aware of yourself.

00:16 Now how do I know right now that I’m actually standing this way versus this way? Or how do you know that when you’re leaning your arm against on a counter that it's actually there? So that self-report of being aware of where you are or what you’re doing or what you’re touching is called proprioception.

00:34 You can have a muscle spindle, which is a mechanoreceptor found in certain muscle stretch. Again, as you stretch a muscle, you need that information to be sent back, saying, this muscle is being stretched.

00:46 So there's a lot of feedback senses that are happening. You can have Golgi tendon organs which monitor tension and certain tendons. You can have joint capsule receptors which detect pressure tension and movement in the joints. And you can have the proprioception which I mentioned already. So all of these are providing a lot of feedback towards movement, stance and muscle. All really, really important as well. And a lot of these used to go sort of undetected or unannounced, not by your body but by yourself. Cognitively speaking, you’re not aware of the fact that you’re aware that you are standing in a certain fashion. We’re also going to look at something called your vestibular sense. This is a really neat thing. Again, you very rarely think about this, but this is your sense of balance and spatial orientation, and this helps with coordinating your movement and balance.

01:34 And the only time you’re actually aware of that, you have these vestibular senses when things go awry.

01:39 When you lose your balance, so you get really, really dizzy. That’s when you’re like, “Okay, something’s wrong.” So things like, you know, literally, dizziness or vertigo are linked to some issues with your vestibular sense. So what this does is it coordinates the cochlea, which is found in your ear to determine rotational and translational movement. So I think we all understand what rotational means. That would be movement like this and translational would be movement along an axis this way. So forward to back. Rock, a rocking motion this way. So the two components are usually learning to do different structures. So the semicircular canal system is what mediates and manages the rotational movements. So what it does is, it knows how the rotational movement. Now if you go on a ride at the local carnival that spins you around, that movement tells you that you're upside down, or that you're sitting backwards. And it moves as you move because it's fluid filled. The otoliths indicate linear accelerations. And the two structures in specific are the uttricle and saccule.

02:40 And you can see them here in the diagram. The best analogy for this movement to use is a long tube partly filled with water. As that tube is moved forward and back, that liquid is going to move this way and there is a wave action. That wave action allows you to indicate linear accelerations.

03:00 So all this information is gathered and is sent to the cerebellum for processing. That allows you to get that 3D orientation of where am I in the rotational space and where am I in the translational space.

03:11 So you’re getting all of this information. So collectively, we term that the vestibular sense.

03:15 So we’ve walked through a whole bunch of senses quite quickly, but I hope you appreciate the fact that we do a have a lot of senses. We do interact with our environment. All that information gets processed up in the central nervous system at different brain regions and allows us to process, interpret, and respond to that information.