Emotion Flashcards
What are the two theories of emotion?
→ James-Lange
→ Cannon-Bard
What is the James-Lange theory of emotion?
→ we experience emotions in response to physiological changes in our body
What is the Cannon-Bard theory of emotion?
→ We can experience emotions independently of emotional expression
When are emotions produced?
→ When signals reach the thalamus either directly from sensory receptors or by descending cortical input
What is the brain system responsible for emotion?
→ Broca’s limbic lobe
What are the 3 structures that make up Broca’s limbic lobe?
→ Parahippocampal gyrus
→ Cingulate gyrus
→ Subcallosal gyrus
What 3 areas of the brain form a ring around the corpus callosum?
→ Cingulate Gyrus of the Cingulate Cortex
→ Medial surface of the Temporal lobe
→ Hippocampus
Describe the pathway that emotion takes?
→ Neocortex sends signals to the cingulate cortex which is responsible for emotions
→ this sends a signal via the hippocampus to the hypothalamus where the expression of emotion occurs
What is the proof that the hippocampus is involved in the behavioural expression of emotion?
→ Rabies infects the hippocampus
→ hyperemotional responses
What does a lesion in the anterior thalamus cause?
→ Spontaneous laughing or crying
What are the 3 subdivisions of the hippocampal complex?
→ Dentate gyrus
→ CA1-CA4 subfields
→ Subiculum
What are the 6 structures that make up the limbic system?
→ Cingulate gyrus → Parahippocampal structures → Septal nuclei → Amygdala → Entorhinal cortex → Hippocampal complex
What is the function of the limbic system?
→ Attaches behavioural significance and response to a stimulus
What does damage to the limbic system in animals cause?
→ profound effects on emotional responsiveness
What are the 3 roles of the cingulate gyrus?
→ Complex motor control
→ Pain perception
→ Social interactions/mood
What roles do the hippocampus and the para-hippocampal areas have?
→ memory
What is the function of the amygdala?
→ Involved in learning and storage of emotional aspects of experience
What are the 2 ways to find out the function of a structure in the brain?
→ Lesion brain part
→ Hyperactivate it
Where is there activity during fear?
→ Activity in the amygdala
What emotions does the amygdala control?
→ Fear
→ Anxiety
→ Aggression
Where is the amygdala found?
→ Near the hippocampus
What are the 3 subnuclei of the amygdala?
→ Corticomedial nuclei
→ Central nucleus
→ Basolateral nucleus
Where does the amygdala receive input from?
→ The neocortex
→ All lobes including the hippocampal and cingulate gyri
What do the basolateral nuclei receive information from?
→ ALL sensory systems
What is the output of the amygdala?
→ Hypothalamus
What are the amygdala output pathways?
→ Stria terminalis
→ Ventral amygdalofugal pathway
What happens when the temporal lobe is removed in animals?
→ Psychic blindness
→ Oral tendencies
→ Emotional changes
→ Altered sexual behaviour
What does an amygdalectomy do?
→ Reduces fear
→ Reduces aggression
→ reduces ability to recognize a fearful expression
→ Flattened emotion
What happens if you hyperactivate the amygdala?
→ INcreased vigilance
→ Anxiety
→ Fear
→ Aggression
What is the amygdala involved in?
→ PTSD
→ Giving emotional content to memories
What are the two types of aggression?
→ Predatory aggression
→ Affective aggression
What is predatory aggression?
→ Attacks made against a member of a different species to obtain food
→ No sympathetic activity
What is affective aggression?
→ For show
→ Threatening postures
→ Social hierarchy
→ High levels of sympathetic activity
What are the two surgeries to reduce human aggression?
→ Amygdalaectomy
→ Psychosurgery
What are the effects of psychosurgery?
→ Reduced aggressive behaviour
→ relief from anxiety
→ Unpleasant side effects
What happens when you remove the cerebral hemispheres but not the hypothalamus?
→ sham rage
What happens when you remove both cerebral hemispheres and the anterior hypothalamus?
→ sham rage
What happens when you remove the posterior hypothalamus?
→ No sham rage
What does electrical stimulation of the hypothalamus lead to?
→ Effective and predatory aggression
What is affective aggression elicited by?
→ Stimulating the medial hypothalamus
What is predatory aggression elicited by?
→ Stimulating the lateral hypothalamus
What are the 2 structures involved with predatory aggression?
→Medial forebrain bundles
→ Ventral tegmental area
What are the 2 structures involved with affective aggression?
→ Dorsal longitudinal fasciculus
→ Periaqueductal grey matter
How is aggression related to serotonin?
→ inversely related to serotonergic activity
What antagonists increases aggression?
→ 5HT antagonists
What agonists decrease aggression?
→ 5HT1A
→ 5HT1B
