L1- Emotion 1 ( Fear& Anxiety)

What are emotions according to Edmund Rolls?

States elicited by rewarding (S+) or aversive stimuli (S-) and their omission (-) or termination (!), comprising thoughts, feelings, and behavioral responses.

Why are emotional responses to stimuli important from an evolutionary perspective?

They have survival value and have been preserved through evolution, often being similar in humans and animals.

What are the advantages of using rats as a model system in emotional research?

Easy to breed and keep, well-established behavioral tests, well-characterized brain anatomy, and ability to apply selective manipulations.

What are the disadvantages of using rats as a model system?

Genetic manipulations used to be difficult; an alternative is using mice.

What brain structures are involved in the emotional brain according to classic theories?

Hippocampus, amygdala, and hypothalamus.

What is the significance of the Papez theory of emotion?

It was proposed in 1937 and describes the neural circuit involved in emotional expression.

What is the difference between fear and anxiety?

Fear refers to phasic escape or avoidance responses to distinct aversive stimuli, while anxiety refers to a tonic response to diffuse aversive situations associated with conflict and uncertainty.

What are some common fear and anxiety disorders?

OCD, panic disorders, PTSD, and phobias.

What is classical fear conditioning?

It involves pairing a neutral stimulus (tone) with an aversive stimulus (foot shock) to elicit a conditioned fear response.

What role does the amygdala play in conditioned fear?

It serves as the learning hub where associations between stimuli are formed and processed.

What are the outputs of the Central Nucleus (CE) of the amygdala?

It triggers freezing behavior, autonomic responses (blood pressure), and endocrine responses (hormones).

What happens to freezing behavior when the Lateral Amygdala (LA) is lesioned?

There is a massive reduction in freezing behavior compared to control groups.

How do lesions in the Central Gray (CG) affect fear responses?

They cause a significant reduction in freezing behavior but have no effect on blood pressure responses.

What is the significance of the hippocampus in fear and anxiety?

The ventral hippocampus is crucial for conditioned fear responses, while lesions can reduce innate anxiety.

What findings did Richmond et al. (1999) report regarding the hippocampus and learned fear?

Lesions to the ventral hippocampus significantly reduced freezing behavior in response to learned threats.

What did Kjelstrup et al. (2002) find about the hippocampus and innate anxiety?

Rats with ventral or complete hippocampal lesions entered open arms of a maze more often, indicating reduced innate anxiety.

What is the relationship between hippocampal lesions and anxiolytic drugs?

Both show similar behavioral effects, suggesting anxiolytics may mimic the effects of hippocampal lesions.

What did Bremner et al. (2000) discover about panic disorder and the hippocampus?

Patients with panic disorder have fewer benzodiazepine receptors in the left hippocampus compared to healthy controls.

What is the role of the amygdala in emotional learning?

It is essential for processing conditioned fear, as shown by the lack of skin conductance response in patients with amygdala damage.

What is the significance of the case of Patient SM046?

It illustrates that amygdala damage prevents learning a fear response while leaving factual memory intact.

How does the amygdala respond during the acquisition phase of fear conditioning?

It is most active during the early acquisition phase when the brain is learning a new threat.

What is the effect of trials on the firing patterns of neurons in the Lateral Amygdala?

As training trials increase, the neural response strengthens, showing increased spike activity in response to the conditioned stimulus.

What is the role of the Lateral Amygdala (LA) in conditioned fear?

It is responsible for learning the association between the neutral tone and the painful shock.

What is the difference between the Dorsal and Ventral Hippocampus in terms of learned fear?

Ventral lesions significantly impair freezing responses, while Dorsal lesions do not have as severe an effect.

What is the significance of the Central Nucleus (CE) in fear responses?

It acts as the final output station for triggering physiological and behavioral fear responses.

What is the relationship between the amygdala and other brain structures in fear processing?

Other structures like the hippocampus and prefrontal cortex also contribute to fear and anxiety, but their substrates may differ.