Limbic System 1 Flashcards
Constitute a harmonious mechanism which may elaborate the functions of central emotion as well as participate in the emotional expression
Hypothalamus, anterior thalamic nuclei, cingulate gyrus, and hippocampus
Cholinergic neurons that project to the entire cortex
Nucleus Basalis of Meynert
Play a role in attention, memory, and learning
Nucleus Basalis of Meynert
Located Dorsal to the anterior commissure
Septal Nuclei
Connects the nucleus basalis of meynert and the septal nuclei
Nucleus of the diagonal band
Part of the basal ganglia “limbic loop”
Ventral striatum (N. Accumbens)
The anterior nuclei of the thalamus is related to
Learning and Memory
The dorsomedial nucleus of the thalamus is related to
Emotions
What are the 4 main structures of the temporal lobe?
Hippocampus, Amygdala, Parahippocampal gyrus, and Uncus
Located anterior to the hippocampus in the temporal lobe
Amygdala
Almond shaped and is a corticoid area, where the cortex merges with nuclei
Amygdala
The main output of the hippocampus
Fornix
Projects to the mammillary bodies, septal nuclei, and anterior thalamic nucleus
Fornix
Located postcommissural to mammillary bodies and precommissural to septal nuclei
Fornix
Responsible for decision-making, emotional regulation, and complex social interactions
Orbitofrontal and medial prefrontal cortex
The orbitofrontal and medial prefrontal cortex are referred to as the
Seat of personality
What are the three emotions that are present for 90% of the day?
Joy, Love, and Anxiety
Link Sensory Stimuli and Hypothalamic and Brainstem Centers
Emotional centers
If sensory stimuli are emotionally salient, emotion systems are activated, and activate centers in the
Brainstem’s reticular formation and Hypothalamus
Has circuits for coordination cranial nerve motor output
Ponto-medullary reticular formation
The mesencephalic and rostral pontine reticular formation modulates
Forebrain activity
The caudal pontine and medullar reticular formation is responsible for premotor coordination of
Lower somatic and viseral motor neuron pools
Small lesions in brainstems reticular formation can produce uncontrolled
Laughing, crying, and hiccupping
Causes a loss of BOTH upper and lower half of the face for emotional expression
Lesion of pathway from forebrain to hypothalamus
IT should be noted that some bilateral lesions of the corticobulbar tract can produce
Uncontrolled laughing
Assigns value to stimuli (i.e. good vs. bad)
Amygdala
Allows us to choose the appropriate reaction to our conditions
Amygdala
Made up of 12 nuclei divided into 3 nuclear groups
Amygdala
What are the three nuclear groups?
Medial nuclei, Basolateral nuclei, and Central nuclei
Connectto olfactory bulb and cortex
Medial Nuclei
Well developed in humans. Receives direct sensory input from the thalamus and sensory cortices. Connects to orbital and prefrontal cortex
Basolateral Nuclei
The output nuclei: They project to the hypothalamus and brainstem
Central Nucleus
The amygdala receives sensory inputs from the
Thalamus
Main projection from limbic system and hypothalamus to brainstem
Medial forebrain bundle
The amygdala’s connection to the hippocampus enable the
Emotional charging of memories
Olfactory inputs to the amygdala are either direct from olfactory tract or indirect from the
Piriform cortex
Links sensory information cortex and thalamus to the hypothalamic and brainstem centers
Amygdala
The upper connections from the amygdala are responsible for
Behavioral responses and focusing attnetion
The Lower connections from the amygdala are responsible for
Visceral and autonomic responses including arousal
Conditioned stimulus causes an increase in synaptic strength in the amygdala inputs from
-Called synaptic plasticity
Auditor Receptors