Emotion Flashcards
Define affective neuroscience.
The study of emotions in the brain.
Why are ‘feelings’ not a scientific term?
Feelings are subjective experiences - we need a more concrete entity that can be externally assessed.
Define an emotion.
A consistent and discrete response to a significant event.
What are emotions used for in the brain?
To help organise cognitive function and direct an appropriate response.
Emotions can be thought of as point on an axis. What are the two axes?
Arousal and valence.
What does arousal mean?
State of alertness, from sleepy to hyperactive.
What does valence mean?
Either positive of negative.
Many emotions can be easily recognised, regardless of cultural differences. How do we recognise them?
In specific facial expressions.
Facial expressions associated with different emotions can be elicited via stimulation of one or more facial muscle groups. True or false?
True.
Arousal can be characterised by an increases in which physiological factors?
Heart rate, blood pressure, sweat production etc.
Which part of the nervous system controls arousal?
The autonomic nervous system.
Arousing emotions are said to be what kind of responses?
‘Gut’ responses, as in there are visceral components.
Who hypothesised in the 19th century that the cognitive experience of emotion is secondary to the physiological response?
William James and Carl Lange.
Give 4 reasons why James and Lange’s theory was wrong.
- Emotions can develop in less than a second, autonomic responses take longer
- Emotions are very specific, autonomic responses are usually identical
- Emotions continue after the physiological stimuli has subsided
- Lesions to the hypothalamus can lead to rage
In the early 20th century Walter Cannon and Phillip Bard suggested what about the emotional response?
It is organised by the hypothalamus and communicated via the thalamus to the cortex for cognition.
Most modern theories assume that emotion are communicated to awareness a) directly and b) indirectly. What does this mean?
a) Directly via emotional processing centres in the brain
b) Indirectly as the body senses autonomic responses
Work by Schachter has shown that emotion is a construct of the mind. How did he show this?
He injected subjects with adrenalin, which increases heart rate. Subjects normally associated increased heart rate with emotion, but modulated this interpretation knowing the effects were due to adrenalin.
What is the most modern theory of emotional control?
The autonomic response is coordinated by the hypothalamus. Emotions also require cortical processing, largely involving the prefrontal cortex.
Patients with cortical lesions cannot form smiles on request but can form natural smiles, for example is response to a joke. What does this tell us about the generation of facial emotion?
There is likely to be more than one pathway. One for volitional gestures and one for automatic responses.
What components would a pathway that generates volitional gestures require?
Motor cortex involvement and basal ganglia.
Would a pathway that generates automatic responses require the motor cortex?
No.
Define the amygdala.
A small, almond-shaped nucleus in the temporal lobe.
Define the limbic system.
A networks of nerves and brain areas associated with instinct and emotion.
Why has the limbic system hypothesis become increasingly weak?
The numbers of structures assigned to it has grown, and its explanatory power has thus reduced.
In the original limbic system hypothesis first put forward by Papez in 1937, what was the main structure in the temporal lobe responsible for organising an emotional response?
The hippocampus.
The hippocampus is no longer believed to organise the emotional response. Which structure has taken its place?
The amygdala.
By who and when was it proposed that the amygdala coordinates the emotional response?
By Weiskrantz in 1956.
What is Urbach-Wiethe disease?
A reduction in the capability to recognise fear in the faces of others.
What can cause Urbach-Wiethe’s disease?
Damage to the amygdala.
What happens via brief electrical stimulation of the amygdala in humans, shown by Lauteaume in 2007?
It causes fear and apprehension.
In experiments by Whalen et al. in 2004, what happened when subjects were exposed to images of ‘fearful eyes’?
There was an increased BOLD signal in the amygdala.
In experiments by Pegna et al. in 2005, subjects with visual cortical impairment showed what kind of response to ‘emotional’ faces, not necessarily fearful?
An increased BOLD signal in the amygdala.
What did both the control and visually impaired subjects do in the experiments of Pegna et al in 2005?
Unconsciously imitated the expressions they were shown, even though the visually impaired couldn’t tell what the emotion was.
What do the experiments by Lanteaume, Whalen and Pegna all indicate?
The amygdala is necessary and sufficient for emotional response and awareness.
What is the dual input hypothesis?
The amygdala receives inputs from 2 pathways, providing 2 routes for emotion.
What are the 2 pathways that input the amygdala in the dual route hypothesis?
- A rapid pathway through the thalamus
2. A slower pathway through the cortex
It is thought that the rapid thalamic pathway does what to the amygdala?
Primes it for cortical inputs, which are more refined and convey more information about a potential threat.
The amygdala is often described as an ancient structure. True or false?
True: it is highly conserved across mammalian species.
Define fear conditioning.
An unconditioned, negative stimulus like an electric shock is repeatedly presented with a neutral stimulus like a noise, until the organism associates the neutral stimulus with pain and responds in a fearful manner, even when the negative stimulus is no longer present. The negative stimulus now becomes a conditioned stimulus.
In fear conditioning what activity has been observed in the amygdala?
Sensory inputs from single neurons send signals to the central nucleus of the amygdala. This then coordinates the relevant brain areas.
The amygdala appears to have both direct and indirect connections with structures involved in all the major cognitive functions. True or false? If so, what might this mean?
True: it means emotions may impact other systems such as reward, memory and sensation.
Work by Talarico and Rubin in 2003 found that emotions seem to have what effect on memory?
They increase the salience. Salience is the quality that makes something stand out, thus emotion seemed to make particular memories more intense.
