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Current time:0:00Total duration:7:01

Endocrine system and influence on behavior - Part 2

Video transcript

and so we've kind of got an idea up now about what hormones are and then what organs make them but one thing that confused me for a really long time is the idea of how much of these hormones are in our blood and how they actually get from point A to point B and so I'll make a category for concentration and my first thought when I started thinking about hormones are that these must be just kind of infinitely present in our blood vessel there are an unimaginable amount of blood cells and I just kind of categorized hormones with that level of red blood so it's just a ton of them flowing through our body and so and while there is a wealth of hormones flowing through our body at any given time it's actually a fairly small amount you're talking about picograms per milliliter which is one millionth of one millionth of a gram so so really small amounts I mean let's say that the that the pituitary is wanting to stimulate the adrenal glands it's it's releasing that amount of hormones but it's not it's not a straight shot there is no straight shot to the adrenal gland so it's really just dumping this hormone into the blood and then it's going everywhere almost like your your body showering in this hormone and so very similar to two radio waves which are archons are going everywhere throughout the air but are only picked up by those that are tuned into them the endocrine hormones are flowing all throughout your body but their effect is really determined by where the receptors are located and so when you have these Auto 'king the autocrine signals they're Otakon signals because the receptors are right there at the cell that are making them and paracrine signals their parent angles because the receptors are pretty close to the cells that are making them and the same thing with endocrine system that just means that their receptors are a really long distance away from from where they're being made and so that concentration again is is small but it's everywhere in the body and it's been regulated kind of by to two main ideas you've got you got the idea of metabolism that for every one of these hormones that that actually reaches its destination you know nine or so percent are actually metabolized by the by either the liver or the kidney and the liver breaks these down and ultimately makes bottle and the kidneys breaks these these hormones down and ultimately excretes them into urine but for every one of these hormones that are be made thousands of more are being metabolized and excreted in one way or another from the body and so metabolism is affecting concentration but but secretion is also affecting concentration and secretion affects concentration really through this important idea known as that as a feedback loop and so I went ahead and pre-drill a clue that I'll walk us through and so the idea behind a feedback loop is that the products that are being made in and causing that stimulation in different parts of the body also stimulate the cessation or the stopping at the production of the hormones themselves so that's a little bit of a confusing idea and I'll walk us through an example so so say we need more thyroid hormones and our hypothalamus starts releasing thyroid releasing hormones which is how it communicates to anterior pituitary that we need these hormones in our blood the anterior pituitary then releases thyroid stimulating hormone which stimulates the the thyroids production of the thyroid hormones like we talked about t3 and t4 so triiodothyronine and thyroxine so as these thyroid hormones travel through the blood again they're going everywhere in the blood not just from point A to point B they're there in all of the blood vessels and they're just bathing the body's tissues in these hormones they eventually reach receptors on the hypothalamus and anterior pituitary which which we met that died roid hormone is received signals the anterior pituitary to stop the production I'll draw that in red so it's just really clear it signals to to stop the production of these hormones and it does that in the anterior pituitary and also in the hypothalamus it says we don't need these hormones anymore there are plenty of it and that's oh that's a really beautiful effect when you think about it that the body is kind of naturally wired to not only elicit an effect but also to kind of know when that effect is no longer needed and so and so that's the idea of a negative feedback loop and the negative feedback loop is that is the main way that that secretion is controlled and so you have these hormones and you have these organs that are making a menu and you have this idea of regulation and ultimately what that leads in to you is the indican systems involvement with the nervous system in behavior and if behavior is just the coordinated internal and external response of our body and response to its environment then we can see that the the hormones that are signaling these effects in different parts of the body plays a pretty integral role in behavior and then behavior ultimately forms the bridge between the the physiology of the endocrine system and the psychology and the study of the mind and how we how we respond in attitude and personality and all of those effects that are that we talked about in behavior psyche psychologically the the basis for those effects are the coordinated hormonal responses that are happening through the through the endocrine system and so in this bridge between the physiology and psychology that's where you start getting into ideas of cognitive behavioral therapy and cognitive behavioral therapy is this idea that that you can actually you know control parts of what your body is doing physiologically with your mind it's under conscious control these these little hormones and so you can imagine that when you when you're really afraid I'll draw like being being really afraid there that you have epinephrine just coursing through your blood vessels causing an increased heart rate and increased respiratory rate and diverting energy away from your digestion and your immune system in into this kind of fight flight or fight or flight response but that actually become conditioned to that fearful stimulus and as you you know are no longer afraid of it that you can actually become more consciously calm and and resulting and less adrenaline flowing throughout your body and so this entire mass of hormones that are that are circulating through your body at any given moment are in some way under your control and and that's actually a pretty neat concept