Task 5

Question 1

What kinds of responses are emotions made up of?

Answer 1

1. Physiological responses – Changes in heart rate, increased perspiration and respiration.
2. Overt behaviors – Facial expressions, vocal tone and posture.
3. Conscious feelings – Subjective experiences of sadness, happiness, and so on.

Question 2

What happens during the fight or flight response?

Answer 2

In a frightful situation, the autonomic nervous system (ANS) releases
stress hormones (adrenaline) and glucocorticoids (cortisol), which “control the Fight-or-
Flight response”.
Increase in: Respiration, heart-rate, blood pressure, blood glucose, stress hormones
Energy flow to: Large muscle groups, pain suppression, reflexes, perception/awareness
Energy taken from: Digestion, reproduction, immune system, touch receptors

Question 3

What is the James-Lange theory of emotion?

Answer 3

• James-Lange theory of emotion – Conscious feelings of emotion depends on what our body is telling us  “We are afraid because we run”.

Question 4

What is the modern emotional theory?

Answer 4

• Emotional stimuli give rise to bodily responses, which, interpreted in certain context, give rise to conscious feelings of emotion.

Question 5

How do emotions influence storage and retrieval of memories?

Answer 5

Encoding
- experiment w/ story: traumatic story was remembered better
Retrieval
- experiment w/ recall of autobiographical memory: participant could remember things better if they were congruent with their mood (emotion as a memory cue)
- Flashbulb memories
- features are very vivid but incomplete and can contain inaccurate details

Question 6

What types of learning of emotional responses are there?

Answer 6

• Conditioned Emotional Responses: fast, long-lasting and hard to extinguish
• Conditioned Avoidance: example of instrumental conditioning
• Learned Helplessness

Question 7

How did the experiment which showed prediction of danger in rats look like?

Answer 7

Before pairing with a US, a tone CS evokes a mild increase in blood pressure (a) and a brief period of freezing (b). This is an unlearned startle response. After, the tone CS is paired with a foot-shock US. After pairing, the tone CS evokes a strong increase in blood pressure (a) and extended freezing (b). These are conditioned emotional responses, indicating that the rat has learned CS-US association.

Question 8

How did the experiment which showed rat’s learning of avoiding danger look like?

Answer 8

-> Rats are shocked when going into dark section
X Rat remembers earlier unpleasant experience -> freeze as soon as it is placed in experimental apparatus -> CR to experimental context.
X Rat delays before it crosses into dark area and will not spend much time there (avoidance) -> Instrumental conditioning.
- Instrumental conditioning – Stimulus S (= apparatus) -> Response R (= entering dark area) -> Consequence C (= getting shock).

Question 9

What brain systems have special roles in emotional learning and in interpreting the context and monitoring display of emotions?

Answer 9

Emotional learning: Structures of limbic system (incl. thalamus, cingulate cortex, hypothamalus, amygdala)
Interpreting: Frontal cortex

Question 10

What is the amygdala important for? Name the three nuclei! (there are 10)

Answer 10

• learned emotional responses

- emotional modulation of memory storage and retrieval

Question 11

Lateral nucleus

Answer 11

– Primary entry point for sensory information into amygdala – This information comes from thalamus (= sensory gateway to brain) and cortex.

Question 12

Central nucleus

Answer 12

Projects out of amygdala to:

a. ANS – Driving expression of physiological responses (arousal, release of stress hormones).
b. Motor centers – Driving expression of behavioral responses (freezing, startle).

Question 13

Basolateral nucleus

Answer 13

– Projects to cortex, basal ganglia and hippocampus (memory storage areas). It also provides pathway by which emotion modulates memory storage and retrieval in those structures.

Question 14

What can be seen in patients with bilateral amygdala damage?

Answer 14

Disrupted ability to learn and display new emotional responses

• Experiment of skin conductance response: Patient with bilateral amygdala damage responds to US, but cannot learn emotional response to CS.
• > Amygdala lesions damage central nucleus, disrupting ability to express learned fear response, because the damage disrupts major output pathway to ANS and motor centers, that drive freezing response.

Question 15

What two pathways are there concerning the amygdala and emotional learning?

Answer 15

Direct pathway – Faster (12ms) but conveys less detail -> Fast and rough. (thalamus -> amygdala)
Indirect pathway – Slower (19ms) but involvement of cortex allows finer discrimination of stimulus details -> Slow but accurate. (thalamus -> cortex -> amygdala)

Question 16

What can be seen in the lateral nucleus of rats in learning?

Answer 16

X Experiment with rats and odor – Rats were presented with various odors (almond and anise) and trained so that one odor (almond) preceded tail-shock US. Rats quickly learned to freeze in anticipation of shock whenever there was almond odor. To anise odor, they showed no fear response.
->After training, neurons in lateral amygdala responded strongly to almond odor paired with US.

Question 17

Stimulation of amygdala causes dramatic fear response in some animals, but only mild feelings in humans. But why?

Answer 17

Modern emotional theory – Our conscious emotional feelings depend not only on our biological responses, but also on how we interpret the situation.

Question 18

How might amygdala activation affect memory?

Answer 18

Outputs from central nucleus travel to ANS and cause adrenal glands to release stress hormone epinephrine – Helps mediate components of FOF response.
X Epinephrine cannot affect brain directly ->Blood-brain barrier – Membrane that controls passage of substances from blood into CNS.
- Epinephrine cannot cross this barrier, but it can activate brainstem nuclei that produce chemically related norepinephrine, and project it to basolateral amygdala (BLA). From there, outputs travel to brain regions including hippocampus and cortex.
Neurons in BLA fire in rhythmic waves and project to cortex, hippocampal region and other memory sites. Rhythmic activation of many neurons facilitates LTP between coactive neurons. Therefore, BLA may facilitate learning in cortex and hippocampal region.

Question 19

What role does the hippocampus have concerning emotion& memory? (+Experiment)

Answer 19

region critical for new episodic memory formation, but it is not limited to learning about facts/events: it also plays role in nondeclarative memory.
Healthy humans report contextual information about conditioning experiment. Patients with HL cannot report this information – but patient with AL can.
->This suggests a dissociation between conditioned emotional responding (amygdala) and contextual or episodic learning (hippocampus).

Question 20

What role do the frontal lobes have concerning emotion

Answer 20

Involved in social behavior, which demands ability to express emotion and read it in others.

Question 21

What theories are there concerning phobias?

Answer 21

1. Classical conditioning

2. Alternative theory: biologically predisposed fear

Question 22

What treatment methods are there for Phobias?

Answer 22

1. Systematic desensitization – Therapy for phobias where successive approximation of CS are presented, while patient learns to stay relaxed. Eventually, even the CS itself does not elicit a fear response, because the steps are taken very gradually  Slow and painstaking process, but successful and long-lasting.
2. Propranolol – And other drugs, block/interfere with epinephrine and can also help individuals who suffer from phobias. Because it is critical for FOF response to happen, blocking it suppresses body’s response to fear-producing stimuli  Predicted by James-Lange theory of emotions.

Question 23

How do brains of PTSD patients differ from normal brains?

Answer 23

Smaller hippocampal volumes

Question 24

Why might PTSD occur?

Answer 24

Classical conditioning

Question 25

What treatment methods are there for PTSD?

Answer 25

Extinction therapy

Question 26

What are optogenetic tools and what clinical promises do they hold?

Answer 26

Genetically encoded switches that allow neurons to be turned on or off with bursts of light, with unprecedent precision.
Clinical promise: Potential for modulating activity of brain circuits involved in neurological disorders or restoring vision loss.

Question 27

What optogenetic tool turns cells off and off?

Answer 27

1. Algae protein channel-rhodopsin: influx of positive ions after illumination with blue light - ON-switch
2. Archaeal protein halo rhodopsin: influx of negatively-charged ions in response to yellow light - OFF-switch

Question 28

What two circuits were found in the basolateral amygdala involving the two opposite behaviors fear and reward learning?

Answer 28

1. Nucleus accumbens projects to reward center -> Stimulation of reward center projection enhances positive reinforcement and feeling of safety.
2. Centro-medial amygdala projects to fear center -> Stimulation of fear center projection promotes negative reinforcement.

Question 29

What study has been done on mice concerning memory suppression?

Answer 29

– Mice were placed in chamber where they received shock. After forming fear-based memory of this place, a light-sensitive protein was inserted into cells that stored that info. Mice were then removed from chamber and later, scientists artificially reactivated memory by shining light into cells holding memory of fearful place. Mice responded by freezing and avoiding exploration – They were afraid.
X Activation of hippocampus while in safe environment (with females) – Memory cells in hippocampus acquired new positive emotional association.
-> Proof that memories can be rewired.

Question 30

What types of information are stored in the hippocampus and amygdala?

Answer 30

X Hippocampus – Records contextual information such as place where traumatic event occurred.
X Amygdala – Stores emotional component of memory.