Biology of Fear

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Questions and Answers

What is the frequency of distress calls emitted when an individual is unhappy or stressed?

30 kHz

40 kHz

20 kHz (correct)

60 kHz

Why is psychotherapy a difficult and lengthy process?

Due to the imperfections of the human brain

Because of the asymmetry of connections between the amygdala and neocortex (correct)

Due to the lack of effective communication channels between brain systems

Because of the complexity of human emotions

What is the function of cells in the amygdala that fire in response to objects of fear?

To process emotions related to joy

To suppress the fear response

To regulate emotional responses to facial expressions

To enhance the fear response (correct)

What is the frequency of short, chirping calls that are thought to be positive?

50 kHz Signup and view all the answers

What is the response pattern of intracranial event-related potentials (ERPs) in the human amygdala?

A preferential response to eyes expressing fear and joy Signup and view all the answers

What is the role of the amygdala in processing emotions conveyed by the face?

It processes emotions conveyed by the eye region Signup and view all the answers

How quickly does a visual stimulus travel to the amygdala in humans?

In a few thousandths of a second Signup and view all the answers

What type of facial expressions do cells in the amygdala respond to?

Expressions of fear on faces of other humans Signup and view all the answers

What is the primary function of the amygdala in the brain?

To detect and respond to predators Signup and view all the answers

What is the result of a strong stimulus on the amygdala?

Piloerection and heart racing Signup and view all the answers

What is the primary function of the emotion of disgust?

To avoid things that may cause illness Signup and view all the answers

What is a characteristic of the pathways connecting the amygdala and neocortex?

They are asymmetrical and bidirectional Signup and view all the answers

What is an example of ultrasonic vocalisations in the content?

Rats emitting high-frequency screams Signup and view all the answers

What is the significance of infant distress calls in the context of fear?

Infants cannot regulate their own body temperature Signup and view all the answers

What is the primary function of the emotion of fear?

To alert us to escape from danger Signup and view all the answers

What is the relationship between the amygdala and the neocortex in the context of fear?

The neocortex is activated by the amygdala Signup and view all the answers

What is the key difference between the emotion of fear and the conscious feeling of fear?

The emotion of fear is mediated by the amygdala, while the conscious feeling of fear is mediated by higher cortex. Signup and view all the answers

What is the limitation of the neural connections between the cortex and the amygdala?

Connections down from the cortex to the amygdala are less well developed than connections up from the amygdala to the cortex. Signup and view all the answers

What is the main advantage of using classical fear conditioning to study emotion?

It provides a behavioural measure of the fear that humans experience. Signup and view all the answers

What is the role of the higher cortex in the fear response?

It analyses the frightening stimulus in detail. Signup and view all the answers

What is the significance of the amygdala in the fear response?

It is specialized for reacting to stimuli and triggering a physiological response. Signup and view all the answers

What is the limitation of studying fear conditioning in lab rats and other mammals?

The results may not generalize to humans. Signup and view all the answers

What is the significance of Joseph LeDoux's suggestion about the term 'fear'?

He suggests that the term 'fear' should denote feelings and conscious feelings. Signup and view all the answers

What is the role of the amygdala in determining the significance of a stimulus?

It determines the significance of the stimulus and triggers an emotional response. Signup and view all the answers

What is the difference between the 1st pathway and the 2nd pathway in the fear response?

The 1st pathway is faster and more automatic, while the 2nd pathway is slower and more cognitive. Signup and view all the answers

What is the significance of the amygdala having 12-15 distinct regions?

It suggests that the amygdala is involved in other emotions beyond fear. Signup and view all the answers

What is the primary function of the amygdala in the context of fear responses?

To mediate the unconscious processing of fear stimuli and trigger fear responses Signup and view all the answers

What happens when the cortex tries to abort the amygdala's alarm signals in response to a false alarm?

The person will have a jolt of fear due to initial arousal of the amygdala Signup and view all the answers

What is the role of the hippocampus in the context of fear responses?

To process and store conscious memories of fearful events Signup and view all the answers

What is the primary difference between implicit and explicit memories of fear?

Implicit memories are unconscious, while explicit memories are conscious Signup and view all the answers

What is the function of anandamide in the body?

To influence appetite, memory, pain, depression, and fertility Signup and view all the answers

What is the role of the amygdala in the context of traumatic memory?

To mediate the unconscious processing of fear stimuli Signup and view all the answers

What is the significance of the amygdala in the evolution of fear responses?

It is a conserved feature across species, serving to protect organisms from danger Signup and view all the answers

What is the relationship between the brain's fear response and conscious awareness?

Conscious awareness is necessary for the brain to assess and respond to fear Signup and view all the answers

What is the primary difference between the fear responses in humans and rats?

The stimuli that trigger fear responses are different Signup and view all the answers

What is the role of the cortex in the context of fear responses?

To try to abort the amygdala's alarm signals in response to false alarms Signup and view all the answers

What is the frequency of distress calls emitted when an individual is happy or playing?

50 kHz Signup and view all the answers

What is the role of the amygdala in processing emotions conveyed by facial expressions?

Processing emotions conveyed by the eye region Signup and view all the answers

What is the effect of facial expressions on the amygdala?

It presents a preferential response to eyes expressing fear and joy Signup and view all the answers

What is the significance of the asymmetry of connections between the amygdala and neocortex?

It makes psychotherapy a difficult and lengthy process Signup and view all the answers

What type of calls are emitted when an individual is defeated socially or anticipates pain?

Long distress calls Signup and view all the answers

What is the response of the amygdala to visual stimuli in humans?

It responds in a few thousandths of a second Signup and view all the answers

What is the significance of the amygdala's connection to the neocortex?

It relies on imperfect channels of communication Signup and view all the answers

What is the significance of the amygdala's response to facial expressions?

It is responsive to facial expressions of fear and joy Signup and view all the answers

What is the primary function of the emotion of fear?

To alert us to escape from danger Signup and view all the answers

What happens when a strong stimulus affects the amygdala?

It triggers the release of fight/flight hormones Signup and view all the answers

What is unique about the pathways connecting the amygdala and neocortex?

They are asymmetrical, with stronger connections from amygdala to neocortex Signup and view all the answers

What is the purpose of infant distress calls?

To signal danger or distress Signup and view all the answers

What is the role of the amygdala in the fear response?

To detect and respond to predators or threats Signup and view all the answers

What is an example of an adaptive function of emotions?

Making quick decisions and understanding/communicating needs Signup and view all the answers

What happens when a rat hears another rat's high-frequency scream?

It sends a signal from the auditory cortex to the amygdala Signup and view all the answers

What is the significance of the amygdala's connection to the neocortex?

It allows for rational evaluation of threats before responding Signup and view all the answers

What is the primary function of the amygdala in the brain?

To trigger a physiological response to fear Signup and view all the answers

What is the key difference between the emotion of fear and the conscious feeling of fear?

The emotion of fear is a unconscious response, while the conscious feeling of fear is a conscious response Signup and view all the answers

What is the significance of the amygdala having 12-15 distinct regions?

It suggests that the amygdala plays a role in other emotions beyond fear Signup and view all the answers

What is the limitation of the neural connections between the cortex and the amygdala?

The connections from the cortex to the amygdala are less well developed than those from the amygdala to the cortex Signup and view all the answers

What is the primary function of the higher cortex in the fear response?

To analyse and interpret the significance of a stimulus Signup and view all the answers

What is the significance of Joseph LeDoux's suggestion about the term 'fear'?

It implies that the term 'fear' should only denote conscious feelings of fear Signup and view all the answers

What is the role of the amygdala in determining the significance of a stimulus?

It determines the significance of a stimulus based on sensory information Signup and view all the answers

What is the main advantage of using classical fear conditioning to study emotion?

It provides a clear and precise measure of emotional responses Signup and view all the answers

What is the difference between the 1st pathway and the 2nd pathway in the fear response?

The 1st pathway is fast and mediated by the amygdala, while the 2nd pathway is slow and mediated by the cortex Signup and view all the answers

What is the relationship between the amygdala and the cortex in the context of fear?

The amygdala exerts a greater influence on the cortex than vice versa Signup and view all the answers

What is the primary function of the amygdala in the fear response?

To sit at the centre of the fear circuit and send motor commands Signup and view all the answers

What happens when the cortex tries to abort the amygdala's alarm signals in response to a false alarm?

The person will have a jolt of fear due to initial arousal of the amygdala Signup and view all the answers

What is the primary difference between implicit and explicit memories of fear?

Implicit memories are unconscious, while explicit memories are conscious Signup and view all the answers

What is the role of anandamide in the body?

It is a neurotransmitter that influences appetite, memory, pain, depression, and fertility Signup and view all the answers

What is the significance of the amygdala in the evolution of fear responses?

It is a critical component of the fear response that has been conserved across species Signup and view all the answers

What is the relationship between the brain's fear response and conscious awareness?

The brain's fear response can occur without conscious awareness, but conscious awareness can modify the response Signup and view all the answers

What is the primary difference between the fear responses in humans and rats?

The fear response in humans is more complex and involves conscious awareness Signup and view all the answers

What is the role of the hippocampus in the context of fear responses?

It is involved in the formation of explicit memories of fear Signup and view all the answers

What is the significance of the amygdala in the context of traumatic memory?

It is involved in the formation of implicit memories of fear, which are associated with traumatic experiences Signup and view all the answers

What is the result of damage to the amygdala in humans?

The person will have a reduced fear response Signup and view all the answers

Study Notes

Fear alerts us to escape from danger, while anger directs us to attack an intruder, and disgust tells us to avoid things that may cause illness.

Amygdala

The amygdala is designed to detect predators and remains quiet most of the time.
A strong stimulus can result in piloerection (hair standing on end), heart racing, and fight/flight hormones flooding the body.
The amygdala is specialized for reacting to stimuli and triggering a physiological response of fear.

Fear System of the Brain

The pathways connecting the amygdala (emotional processing system of fear) with the neocortex (thinking brain) are not symmetrical.
Connections from the neocortex to the amygdala are much weaker than those from the amygdala to the neocortex.
This may be why once an emotion is aroused, it is hard for us to turn it off at will.

ULTRASONIC RAT VOCALISATIONS

Rats emit high-frequency screams when threatened, which activates the amygdala in other rats.
Infants emit high-pitched distress calls (40 kHz) when cold, and long distress calls (20 kHz) when unhappy or stressed.
Short, chirping calls (50 kHz) are thought to be positive, associated with play, courtship, and feeding.

Human Amygdala

The human amygdala responds to a visual stimulus (e.g., a snake) in a few thousandths of a second.
The amygdala contains cells that fire in response to expressions of fear on faces and objects of fear (snakes).
The amygdala has a special role in processing emotions conveyed by the eye region of the face.

Emotion vs. Feeling of 'Fear'

The amygdala is responsible for reacting to stimuli and triggering a physiological response of fear.
The conscious feeling of fear arises from a slower, second pathway involving the higher cortex.

Classical Fear Conditioning

Fear conditioning is used to study emotion in humans and animals.
Results from studies in lab rats and other mammals have helped map the fear system of the brain.

Physiology vs. Feeling of 'Fear'

Fear is used scientifically in two ways: conscious feelings and behavioral/physiological responses.
Joseph LeDoux suggests that 'fear' should denote feelings and be used for responses.

Human Emotion of Fear

For traumatic memory, two memory systems are important: explicit (conscious) memories and implicit (unconscious) memories.
The amygdala and hippocampus are involved in different memory systems.
If the fear message is a false alarm, the cortex tries to abort the amygdala's alarm signals.

Amygdala and Fear Responses Across Species

The amygdala of reptiles and birds has similar functions to humans.
The brain's responses to danger appear similar across species, despite different stimuli triggering fear.
In humans, once the fear system detects and responds to danger, the complex brain assesses the situation and tries to figure out a response.