Module 40 - Emotions Flashcards
What are the two different ways all emotions are expressed?
- All emotions are expressed in 2 ways:
- Visceral motor changes → the feeling you get into your gut when you are nervous, for example.
- Somatic motor responses (facial muscles)
True or false: All emotions are accompanied by subjective experiences.
True
How are all emotions accompanied by subjective experience but similar across all human cultures?
Generally being happy is a pleasant state whereas sad is an unpleasant state → and all humans have the same perception of how happy is good but sad is not.
What are some of the visceral (autonomic) motor system changes?
- Heart rate
- Cutaneous blood flow
- Piloerection
- Sweating
- Gastrointestinal motility
What controls/ brings on the various visceral motor system changes?
- Heart rate, Cutaneous blood flow, Piloerection, Sweating and Gastrointestinal motility → are all brought on by changes in the activation of sympathetic, parasympathetic, and enteric components of the visceral motor system.
- The sympathetic system = fight or flight
- Parasympathetic/enteric systems = rest and digest
What does this quote mean: “ the desire for food and drink… the pleasures of the table are nothing in the presence of anger or great anxiety. “
This visceral response to emotions can sometimes override other things. For example, if you are under a lot of stress, a neuroscience midterm and you’re anxious, but it was your friends birthday the night before and all your friends are going out and having a good time; sometimes it is really difficult to turn off the anxiety or negative emotions for the test that you have the next morning in order to enjoy the evening. → fight or flight system on overdrive.
What is the overall message to take away from this quote: “What kind of emotion of fear would be left if the feeling neither of quickened heart-beats nor of shallow breathing… neither of goose-flesh nor of visceral stirrings… I say that for us emotion dissociated from all bodily feeling is inconceivable.” - William James, 1983
- Emotion and sensorimotor behavior are inextricably linked
- Our emotions and our body is a two-way street
What is a somatic motor response?
- Somatic motor responses are the cortex, the premotor cortex, and the typical facial muscles.
- Example, smiling, tensing up your muscles
What are the two mechanisms of control of our somatic motor response?
Voluntary (classical motor pathways)
Involuntary/automatic (limbic system)
What is one of the main functions of the brainstem reticular formation?
This is part of the brainstem that keeps up awake and alert.
Explain the descending systems that control somatic and visceral motor effectors in the expression of emotion.
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What descending structures are responsible for the emotional expression/ involuntary control of our somatic motor response?
Descending “extrapyramidal” projections from “limbic” centers of ventral-medial forebrain and hypothalamus
Explain each scenario in the following image
- (1) Duchenne and one of his subjects undergoing faradization of the facial muscles → which is with the use of transcutaneous electrical stimulation to activate single muscles and small groups of muscles in the face, dorsal surface of the head, and neck.
- (2) Bilateral electrical stimulation of the zygomaticus major mimicked a genuine expression of happiness…
- …(3) although closer examination shows insufficient contraction of the orbicular oculi (surrounding the eyes) compared with spontaneous laughter.
- (4) Stimulation of the brow and neck produced an expression of “terror mixed with pain, torture.. That of the damned.”; however the man reported no discomfort or emotional experience consistent with the evoked contractions.
What are the two different types of facial paresis?
Voluntary facial paresis
Emotional facial paresis
What structures would be impaired with a voluntary facial paresis?
It is the structures that are responsible for volitional movement → the descending “pyramidal” and “extrapyramidal” projections from motor cortex and brainstem
What structures would be impaired with an emotional facial paresis?
Descending “extrapyramidal” projections from “limbic” centers of ventral-medial forebrain and hypothalamus
What would be a typical voluntary and involuntary smile response for a patient with voluntary facial paresis?
The mouth of a patient with a lesion that destroyed descending fibers from the right motor cortex displaying voluntary facial paresis. When asked to show her teeth, the patient was unable to contract the muscles on the left side of her mouth (upper left), yet her spontaneous smile in response to a humorous remark was nearly symmetrical (lower left).
What would be a typical voluntary and involuntary smile response for a patient with emotional facial paresis?
The mouth of a patient with a lesion that destroyed descending fibers from the forebrain displaying emotional facial paresis. When asked to show her teeth, the patient was able to contract the muscles, yet his spontaneous smile in response to a humorous remark the right side of his face was unable to express emotion.
What are the two anatomical and functional distinct sets of descending projections that motivate the muscles of facial expression? Explain their connection.
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When it comes to emotional expression, what controls the nature of descending motor control for facial musculature?
- There is a DUAL nature of descending motor control for facial musculature.
- There is a voluntary response → motor cortical areas
- There is also an involuntary response → limbic system
The descending inputs from the volitional and emotional/involuntary systems run parallel to each other. Why is this true?
- They both have connections to the reticular formation
- They both have a connection to the somatic motor pools, although they are different motor pools
- This connection between limbic system and body is a “two-way street”. The motor system influences the limbic system/emotional states and vice versa
- A good example of this = mediation
What are the different “sources” of emotion?
- Sensory drive from muscles and internal organs
- This input forms the sensory limb of reflex circuitry that allows rapid physiological changes in response to altered conditions.
- Forebrain
- Anticipated events, suspenseful TV shows, etc all lead to autonomic activation and strongly felt emotions.
How do emotions differ along 2 dimensions?
Intensity (arousal level)
Valence (pleasantness or aversive: approach or avoidance)
Fill out the image below.
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Explain the Papez circuit
IMAGE
What are the structures in this image?
Trace the path of the basic Papez Circuit
IMAGE
The ____________ is connected to target structures that produce behaviors associated with emotions, for example with anger. What are the general systems of target structures?
The hypothalamus is connected to target structures that produce behaviors associated with emotions, for example with anger.
- The target structures are:
- Visceral motor system
- Somatic motor system
- Endocrine system
How does the hypothalamus control expression of emotion via connections to the visceral motor system?
- As you can see from this image, there are projections to the reticular formation, brainstem, and spinal cord autonomic neurons.
- These will then ultimately activate the end organs such as smooth muscle, cardiac muscles, and glands.
How does the hypothalamus control expression of emotion via connections to the endocrine system?
The hypothalamus is connected to the anterior pituitary gland and sends hormones into the bloodstream which then has some indications for our emotional system
Which structure(s) in the brain is believed to express our emotion and which structure(s) in the brain is believed to be responsible for the subjective feeling of emotion?
What we can see, is the hypothalamus and the lower structures/its targets are what express our emotion and perhaps the cortex is what helps us feel the subjective feeling of emotion.
HOW DO WE CONTROL THE HYPOTHALAMUS? WHICH STRUCTURES NORMALLY EXERT DESCENDING CONTROL OVER THE HYPOTHALAMUS? WHAT STRUCTURES ULTIMATELY DECIDE OUR FACIAL EXPRESSIONS AND GUT RESPONSES?
(important question)
- As you can from this diagram, you can see that the hypothalamus is in the middle and there is descending input from the amygdala and above that there is the medial prefrontal cortex and the insular cortex.
What are the four main functions of the limbic system? What is the acronym to remember it?
- HOME = acronym
- Homeostatic Responses
- Hypothalamus
- Survival instinct
- Securing food
- Fight or flight
- Sexual behaviour
- Hypothalamus
- Olfaction
- Olfactory cortex
- Memory
- Hippocampal formation (circuit of Papez)
- Emotional/Goal-Directed Behaviour
- Amygdala
***Disclaimer***
We have all of these connections between these structures, and it is a very complicated system.
Relationship status: it’s complicated LOL
WE need to know the components of the limbic system, but we don’t need to know how it is all connected.
NEED TO KNOW → which components make up the limbic system.
IMAGE
What is the amygdala?
- The amygdala is a group of nuclei, made up of gray matter, in the anteromedial temporal lobe.
- Receives and transmits information from diverse cortical areas (including heteromodal association cortices and limbic cortex)
What is the basal-lateral group of the amygdala?
- It is connected to the cortex, therefore it is connected to the orbital and media prefrontal cortex
- We need to remember that our frontal lobes integrate sensory signals that are important for the planning and prediction of the consequences of different behaviors.
- Conversely, this part of the cortex will also send information back to the amygdala
- The function of the amygdala is to interpret/evaluate the signification of stimuli → meaning that it is evaluating the emotional significance of the stimuli
- The amygdala is also connected to the mediodorsal nucleus of the thalamus and the circular connection to the cortex as well.
What happens to a patient with a loss of amygdala?
- Inability to recognize fear in real life
- Example, no trouble handling snakes and spiders
- But the person is able to feel all the other emotions!
Lateralization of emotion → Is there a hemisphere (right or left) of the brain that is more responsible for emotions?
- Emotion is lateralized in a certain way!
- Many people are “left faced”. The fact that the left side of the face appears to express emotion more fully and readily is consistent with the idea that the right hemisphere is most concerned with the perception and expression of emotion
- Example, aprosody with right hemisphere lesions
What is the limbic lobe in general?
The limbic system refers to a collection of cortical and subcortical regions of the brain primarily associated with regulating emotion, motivation, learning, and memory. The major components of the limbic system include the limbic lobe, the hippocampus, and the amygdala.
What do we mean when we say that the limbic lobe is not a true lobe?
Rather, it comprises a ring of cortex on the medial surface of the brain, spanning aspects of the frontal, parietal, and temporal lobes.
Compare and contrast the hippocampus and amygdala in terms of structural location.
- As seen here, the hippocampus is located deep within the temporal lobe, and serves as the floor of the inferior horn of the lateral ventricle. The amygdala is located just rostral/anterior and medial to the hippocampus.
- The hippocampus:
- Learning
- Memory formation & retrieval
- Site of adult neurogenesis
- Amygdala
- Emotional learning & memory
- Fear
- Reward
Match the types of memory on the left with the examples given on the right
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What is the primary function of the structure indicated on the image?
- Learning
- Memory formation & retrieval
- Site of adult neurogenesis
- All of the above
