Emotion Flashcards
What is emotion?
- Emotional expression
- Emotional experience
- Affective neuroscience
What is james lange’s theory of emotion?
We experience emotion in response to physiological changes in our body
What is cannon bard’s theory of emotion?
We can experience emotion independently of emotional expression
What brain system is responsible for emotions?
The broca’s limbic lobe
What is the broca’s limbic lobe?
It is a primitive cortical gyuri that form a ring around the brain stem
What does the broca’s limb include?
- The parahippocampal gyrus
- The cingulate gyrus
- The subcallosal gyrus
What is the papez circuit?
CHECK NOTES
What takes place in the neocortex in terms of emotion?
This is where emotional coloring takes place
What do we experience at the cingulate cortex in terms of emotion?
This is where we experience emotion
What takes place at the hypothalamus in terms of emotions?
This is where emotional expression takes place
What are the regions involved in the limbic system?
Regions involved:
- Cingulate gyrus
- Parahippocampal structure
- Septal nuclei
- Amygdala
- Entorhinal cortex
- Hippocampal complex
What does the limbic system appear to have a role in?
Appears to have a role in attaching a behavioral significance and response to a stimulus, especially with respect to its emotional content
What is the role of the cingulate gyrus in the limbic system?
- Role in complex motor control
- Pain perception
- Social interactions
What is the primary function of the hippocampus and parahippocampal areas in the limbic system?
-Primary function in memory
What is the amygdala involved in, in the limbic system?
Involved in learning and storage of emotional aspects of experience
What are the difficulties with single emotion system concept?
- Diversity of emotions and brain activity
- Many structures are involved in emotion
What is the amygdala a critical structure for?
Critical structure for emotion, in particular:
- Fear
- Aggression
- Anxiety
What is the amygdala formed of?
Formed of many nuclei and subnuclei:
- Corticomedial nuclei
- Basolateral nuclei
- Central nucleus
Where does the amygdala receive input from?
Receives input from the neocortex
Where does the basolateral nuclei, in the amygdala, receive information from?
Basolateral nuclei receives information from all sensory systems
Where does the amygdala output to?
Output is to the hypothalamus
What is the output to the hypothalamus from the amygdala mediated by?
Mediated by:
- Stria terminalis
- Ventral amygdalofugal pathway
What did animals suffer from when there temporal lobe(temporal cortex, amygdala,hippocampus) was removed?
Suffered from:
- Psychic blindness
- Oral tendencies
- Emotional changes
- Altered sexual behaviour
What are the effects of an amygdalectomy?
- Reduced fear
- Reduced aggression
- Reduced ability to recognise fearful expression
What are the effects of electrical stimulation of the amygdala?
- Increased vigilance
- Anxiety
- Fear
- Aggression
How is the amygdala involved in learned fear?
Amygdala involved in forming memories of emotional and painful events
What confirms learned memory in amygdala?
Confirmed by fMRI images and PET imaging
What is aggression?
Is a multifaceted behaviour
What mechanism is aggression?
Aggression is an endocrine mechanism
What are the 2 brain mechanisms of aggression?
- Predatory aggression
- Affective aggression
What is predatory mechanism?
Attacks made against a member of a different species to obtain food
-No sympathetic activity
What is affective aggression?
- For show, threatening posture
- Social hierarchy
- High levels of sympathetic activity
What surgeries are available to reduce human aggression?
- Amygdalectomy
- Psychosurgery
What are the results of surgery to reduce human aggression?
- Reduced aggressive behaviour
- Relief from anxiety
What can the removal of the amygdala do to an animal?
The removal of the amygdala can transform the animal from being dominant to subordinate
What does the removal of the cerebral hemisphere but not the hypothalamus do in terms of aggression?
Leads to rage
What does the removal of both cerebral hemispheres and the anterior hypothalamus do in terms of aggression?
Leads to rage
What does the removal of the posterior hypothalamus as well as both cerebral hemispheres and anterior hypothalamus do in terms of aggression?
No rage
What does electrical stimulation of the hypothalamus lead to?
Leads to effective and predatory aggression
What is the hypothalamic pathway to the brainstem involving autonomic function in predatory aggression?
Medial forebrain bundle–>Ventral tegmental area
What is the hypothalamic pathway to the brainstem involving autonomic function in affective aggression?
Dorsal longitudinal fasciculus–>Periaqueductal grey matter
What is the serotonin deficiency hypothesis?
Aggression is inversely related to serotonergic activity
What effect does a 5HT antagonist have on aggression?
5HT antagonist increases aggression
What effect do agonists of 5HT1A and 5HT1B have?
Decrease anxiety and aggressiveness
