The Role of Biological Processes in Perceiving Emotion: Emotion and the Autonomic Nervous System – Emotion (PSY, BIO)

00:00 Okay, now.

00:03 Let's walk ourselves through how emotion and the autonomic nervous system have a relationship.

00:11 So we are going to abbreviate autonomic nervous system as ANS as hopefully coming up a lot throughout our lectures.

00:17 So what does the ANS do.

00:19 So the ANS controls involuntary responses.

00:22 And what I'm talking about here, is things that you are not actively thinking about.

00:27 So like the name implies, autonomic, one way to help you remember this for the MCAT exam, is autonomic sounds a lot like automatic.

00:35 And these are things sort of happening automatically.

00:38 These are things that you are not really thinking about doing it, they just happen.

00:41 You can almost say as a reflex.

00:42 So two main systems that we want to talk about is a sympathetic nervous system and then the parasympathetic nervous system.

00:49 The SNS and the PNS.

00:52 So let's walk through both.

00:53 The SNS is often referred to the flight or fight response.

00:58 I'm sure you've heard that before.

00:59 And we're going to get of what that means in a second.

01:03 It involves a brief intense, vigorous response.

01:06 So when I was saying a bear or a lion comes to attack you, the sweating.

01:10 The increase in blood pressure.

01:12 That increase heart rate.

01:13 All those activities, all those responses that you are seeing, those are mediated by this SNS, or sympathetic nervous system.

01:22 It also activates a specific set of glands which are very, very important called the Adrenal Glands to release something called Stress Hormone.

01:29 And this can include things like epinephrine and norepinephrine.

01:32 More commonly known as adrenaline or noradrenaline.

01:36 So you may have heard that analogy, or there is a flush of adrenaline in my blood and we're referring to here is this release of epinephrine and norepinephrine from these adrenal glands.

01:48 So when you are presented with that situation of a bear is attacking you or lion is coming to attack you.

01:56 Or let's relate something to your every day scenario.

01:58 You know, your wife confronts you.

02:00 You have two options there.

02:02 You can fight with your wife, or the lion or the bear.

02:06 Or you can turn around and run away.

02:08 And so evolutionary speaking this was a survival instinct.

02:12 And what they were trying to do in caveman days, well say, I'm being attacked by a saber-toothed tiger.

02:18 I can either fight the saber-toothed tiger with my stick and flint.

02:24 Or I can run back to my cave in order to survive.

02:27 So you really have two options.

02:29 Two broad bends.

02:30 I'm going to fight or I'm going to run away.

02:33 And this is something that happens almost instantaneously.

02:36 And so some individuals tend to almost always want to fight.

02:40 And some individuals might always run away.

02:43 So you might ask yourself right now, what are those scenarios that happened to you.

02:47 You probably know.

02:48 Am I one that's going to turn around and put up my fist and fight.

02:51 Or am I going to be the one that runs away.

02:53 Are they good options.

02:55 Whatever helps you to stay alive, right.

02:57 Now when this happens, the response that you get, the increase in blood pressure, heart rate and sweating, is almost instantaneous.

03:06 And that release that happens of those hormones, is also very, very quick.

03:10 Now the other side is the peripheral nervous system.

03:15 And this is something that's a little bit slower.

03:16 And it's often referred to as the rest-and-digest response versus the fight or flight.

03:22 So we're thinking fight or flight, that's quick lot of action, versus rest-and-digest, slow like the name implies.

03:29 Rest-and-digest.

03:30 So what are we talking about here.

03:31 This is a situation where your body is saying it's time to calm down.

03:36 Take it easy to rest.

03:38 Now the reason there is saying, the reason we are saying rest-and-digest, because we are referring to, the body saying, "I need to activate certain systems that allow me to conserve my energy and increase the process of digestion.

03:52 So think of Thanksgiving or Christmas or big meal that you have.

03:57 I went to mama's house because she is so happy that you did so well in the MCAT exam.

04:01 And she made you your favorite.

04:02 And you are sitting there and eating your big bowl of your favorite.

04:06 And what do you do right after that.

04:07 You undo your pants and you lie down on the sofa and you say, "Oh, mama, you outdid yourself this time," right.

04:12 And you tend to kind of calm down.

04:15 May be dose off.

04:16 You rub your belly and you say what a day.

04:18 Now what's happening there is you are actually activating the parasympathetic nervous system and you are activating that rest-and-digest response.

04:25 And we are telling the internal organs that we're safe.

04:29 There's nothing of danger around us.

04:31 And we can use this time to help conserve our energy.

04:36 Digest this food and actually repair body tissues.

04:39 Now back to my caveman example.

04:41 When the caveman is confronted with this, saber-toothed tiger, it has to fight or run away.

04:49 At that point the body actually starts trimming off unnecessary responses.

04:54 Things like, it doesn't really need to digest food.

04:56 It doesn't really need to bring blood supply to the extremities.

05:01 It's more focused on increasing blood supply to the heart.

05:03 Because it needs it because your heart is pumping.

05:06 It needs more oxygen.

05:07 It needs to delivery more glucose or food to the parts of the body that they needs to either fight this tiger or run away.

05:15 Okay, so it actually does something where it increases your immune response or the ability to fight off and attack.

05:23 Now in this scenario rest-and-digest, the opposite is happening.

05:27 The tiger attack is complete.

05:29 You either run away to your cave or finish beating the tiger.

05:33 And now you're body needs to calm down.

05:37 It needs to conserve this energy.

05:39 And it needs to repair itself.

05:40 Because the tiger gave you a pretty good beating even though you won.

05:43 It still beats you up pretty good.

05:44 And it needs to repair yourself.

05:46 And so this what that happens.

05:48 And this is the system that mediates that.

05:50 The parasympathetic nervous system.