Task 5 - Limbic System Flashcards
(16 cards)
What is evidence to the link between emotion and viscera nervous system?
In a study when, participants where given instructions to produce expressions recognized as anger, disgust, fear, happiness without being told which emotion they are simulating, and the face expression would meet the actual emotion they where feeling, the activity in the VNS was higher.
What is the function of the hypothalamus?
It has a central role in coordination of emotional behaviours
It also targets reticular formation, which controls sleep, wakefulness, cardiovascular function, respiration via its connections with efferent systems in brainstem and spinal cord
What happened in with the cats whose cerebral cortex, white matter and basal ganglia was removed?
They experiences rage (rabia) without target.
The same result came from stimulating the hypothalamus
What are the 2 systems that control movements of meotional expression?
- Voluntary movement component
2. Emotional expression component
Explain the Voluntary movement component
already studied in previous tasks
Motor areas in frontal lobes and related circuitry in basal ganglia and cerebellum –> pyramidal and extrapyramidal projections –> control voluntary movements
Explain emotional expression component
Ventral part of basal ganglia and hypothalamus –> brain stem and reticular formation, then affecting the preganglionic autonomic neurons, somatic premotor and motor neurons –> Movement control
What is the Papez circuit?
–> Limbic system
It shows how the hypothalamus is connected to cingulate cortex:
Emotional stimulus –> thalamus –> sensory and cingulate cortex –> projects to hippocampus –> then hypothalamus –> prjects to anterior thalamus –> back to cingulate cortex –> creates a feeling and bodily response
What is the Klüver-Bucy syndrome?
Syndrome resulting from bilateral lesions of the medial temporal lobe (limbic system)
–> later it was discovered that it can be elicited by the removal of the amygdala alone
It may present with compulsive eating, hypersexuality, insertion of inappropriate objects in the mouth, visual agnosia, and changes in emotional behavior.
Conditioning: All auditory information beep that reaches the forebrain (cortex + limbic system + basal ganglia) travels through medial geniculate nucleus (MGN) of dorsal thalamus.
What happens if you disrup the connections to/from MGN?
If connections between auditory cortex and MGN were severed, fear response remains because connection between MGN and amygdala remains
However, if MGN-amygdala pathway is destroyed –> abolished fear response
What is the neural model for awareness of feeling?
Immediate conscious experience of emotional processing (arises from amygdala associative learning) and explicit processing of semantically based thought (hippocampal explicit memory) –> results in concious experiences (WM in PFC)
What is an emotion?
They are automatic, largely unconscious behavioral and cognitive responses triggered when the brain detects a positively or negatively charged significant stimulus
What is the definition of feeling?
Refers to the conscious experience of these somatic and cognitive changes
What is emotional competence?
Some stimuli-objects, animals, or situations trigger emotions automatically, even in the absence of experience. Competent stimuli can acquire significance through associative learning –> conditioned
What are the 3 systems controlling the physilogical expression of emotional states?
- The endocrine system: Responsible for the secretion and regulation of hormones into the bloodstream that affect bodily tissues and the brain
- The autonomic system: Mediates changes in the physiological control systems of the body, including the cardiovascular system and the visceral organs and tissues in the body cavity
- The skeletal motor system: Mediates overt behaviors such as freezing, fight-or-flight, and particular facial expressions
It was found that most of the limbic areas are not involved in emotional behavior. Nonetheless there was one area that consistently seemed to be involved. Which one?
The amygdala
What are other brain areas contributing to emotional processing?
- Regions of the hypothalamus and brain stem
- The ventral region of the ventromedial prefrontal cortex in various aspects of emotional processing. These cortical circuits are especially important in complex emotional states.
