week 9 part 2 Flashcards
What happened in the mid of 1800’s?
Important time for the development of cognitive, behavioral neuroscience
What were scientists and medics trying to undersyand?
How is emotion regulated (James + Large or Cannon + Bard)
What is theory of emotion proposed by Cannon-Bard?
The experience of emotion occurs alongside our experience of the arousal
What is the theory of James-Lange?
Emotion is the result of arousal, arousal and the emotion are not independent, but rather that the emotion depends on the arousal
What are inter-linked?
The history of limbic system and fear
What were neuroanatomist trying to identify?
Location of behaviour in the brain
William James and Carl Lange (1880’s)
Developed a theory saying that
- Autonomic responses are reflexes that occur quickly
- Emotional experience reflect autonomic reactivity
- This theory of emotion did not explain emotions extend beyond the time of excitation of autonomic system
What did Cannon and Bard argue ?
Emotion was not only produced by autonomic sensation
Central system for emotions in the brain was required
What did Cannon and Bard’s studies suggest?
Hypothalamus and thalamus as a mediators or emotion
These structures could regulate autonomic responses, as well as cognitive side of emotion
What did Cannon and Bard suggest?
- Exposed to experience
- Integrate with a cognitive attribute
- Respond - happens in the hypothalamus and thalamus
What did Paul Broca define and propose?
Defined the limbic lobe
1878: proposed a ring of gray matter on the medial aspect of cerebral hemisphere
he proposed this is where emotions are processd
What did James Papez define?
A limbic system that explains relationship between emotion and memory (Papez circuit)
What does Papez circuit include?
- Cortex
- Parahippocampal gyrus
- Hippocampus
What didn’t the Papez circuitry include?
Amygdala
What did James Papez create?
Modern conception of the limbic system
Where is Papez circuit located?
Ring structure in the border
Between cerebral hemisphere and brainstem
On both side of the thalamus
beneath the cerebrum
What is the limbic system?
A network of cortical and subcortical nuclei interconnected by cortico-cortical pathways
What is the main function of limbic system?
The limbic system regulates emotion
modulates motivation
learning and memory
What is the limbic system considered to be ?
Regulator of the emotional brain
Limbic system
Emotional and motivational aspect of behaviour
provides emotional component to learning associated with memory
especially the hippocampus
Associated with pain/pleasure, anger
What is no longer considered part of the limbic system?
- Hippocampus
2. Mamillary bodies
What does modern limbic system include?
- orbital and medial prefrontal cortex
2. amygdala
What are important in the experience of emotion?
- orbital and medial prefrontal cortex
- Amygdala
- Thalamus
- Hypothalamus
- Ventral tegmentum
What are the key regulators which integrate information in limbic system?
Amygdala
What is integrated in the limbic system?
- Decision making
- Emotional cognition
- Emotional memory
- Fear
What are the components of Limbic system?
- Amygdaloid body (amygdala)
- Hypothalamus
- Cingulate gyrus
- Parahippocampal gyrus
- Anterior nucleus of thalamus
- Prefrontal cortex
What is recognised as a key coordinator of fear processing ?
Amygdala
What does amygdala link?
Cortical processing (PFC) to the hypothalamus and other subcortical brain structures important for emotional behaviour
Amygdala
Relate environmental stimuli to coordinated behavioural autonomic and endocrine responses seen in species-SELF preservation
What are the functions of amygdala?
- Fight/flight behaviour
- Feeding and drinking
- Mating and maternal care
- Responses to physical or emotional stressors
What are 3 types of evidence supporting the role of amygdala in emotional responses?
- Lesions in monkeys amygdala impair normal emotional behaviour
- FMRI studies shows activation of amygdala responds to emotional changes in humans
- Classical fear conditioning is prevented by lesions of lateral nucleus of amygdala in mouse
What did Heinrich Kluver and Paul Bucy do?
Removed the temporal lobes, including the amygdala and hippocampus, bilaterally in humans
They observed a dramatic change in emotional behaviour
What were examples of dramatic change in emotional behaviour?
- Monkeys became tame, fearless and had ‘‘blunted’’ emotions
- Increased oral activity, including placing inedible objects in their mouth
- Exhibited increased sexual behaviour, mounting inappropriate objects
What does damage to lateral nucleus of amygdala prevent?
Acquisition and expression of fear responses to auditory stimulus
What does neural responses to sound and shock converge on?
Same single neuron in lateral nucleus of amygdala
What is response to sound enhanced by?
Conditioning in which the sound is paired with shock
