Lecture 17 Flashcards
4 F’s of limbic system
Fighting / aggression
Flight
Feeding
Fucking
Does olfactory sense always go to the thalamus first?
no, only sense that doesn’t
Olfactory neurons and their synapses
longitudinal striae into limbic system, cortex and thalamus
Anterior olfactory nucleus synapse to
contralateral side
Lateral stria fibers project to
uncus (actually medial part of amygdala which projects to the thalamus and hippocampus)
Emotional Lability
Abrupt mood shifts
Involuntary, inappropriate emotional expression in the absence of subjective emotion
Emotion is triggered by nonspecific stimuli unrelated to the emotional expression.
Motivation
Centered in the medial prefrontal cortex and the ventral striatum
Ventral striatum activity is essential for increasing frequency of rewarded behaviors.
Is the reward worth doing what they’re doing?
Delusions
Simple delusion is common in delirium, Alzheimer’s disease, and vascular dementia.
Complicated delusions occur in schizophrenia and may be medication-induced in Parkinson’s disease
Hallucinations
Are sensory perceptions experienced without corresponding sensory stimuli
There’s visual and auditory hallucinations
Mania
excessive excitement, euphoria, delusions, and overactivity
Racing thoughts, a disregard for consequences, and energetic behaviors typify mania
Causes include drugs, bipolar disorder, and rarely brain lesions on the right side that affect structures in the behavioral flexibility and control loop.
Depression
Is linked to neurotransmitter and neural activity abnormalities rather than to structural abnormalities
People with depression have reduced levels of serotonin metabolites in their cerebrospinal fluid
Anxiety
Autonomic system is overactive, skeletal muscles are tense, and the person is excessively alert
Anxiety Disorders
Generalized anxiety disorder Social anxiety disorder Panic disorder OCD PTSD
Panic Disorder
An episode of intense fear that begins abruptly and lasts 10 to 15 minutes
Obsessive-Compulsive Disorder
Is characterized by persistent upsetting thoughts and the use of compulsive behavior in response to the obsessive thoughts
Post-Traumatic Stress Disorder
People with PTSD re-experience the original event in flashbacks or nightmares, avoid stimuli linked to the trauma, and are hyperaroused.
how emotions are processed inward (Papez Circuit)
from hypothalamus to fornix to Hippocampus
how emotions are processed outward (Papez Circuit)
hypothamamus to mammillary bodies to anterior thalmamic nuclei
Parahippocampal Gyrus
The region plays an important role in memory encoding and retrieval.
Ventral prefrontal and anterior temporal lobe
social behavior and decision making
Structures in the social behavior loop
Ventral prefrontal cortex, head of caudate and substantia nigra
Amygdala function
Fear, anxiety, and risk analysis
Klüver-Bucy Syndrome
bilateral temporal lobe lesions involving the amygdala
stimulation of Lateral hypothalamus
aggression, predatory aggression
stimulation of Medial hypothalamus
changes in expression and personality without anger or aggression
anosmia
lack of smell
hyposmia
decrease in smell
dysosmia
distortion of smell
ageusia
absence of taste
hypogeusia
decreased sensitivity of taste
dysgeusia
distortion of taste
Temporal Lobe Epilepsy
damage to the cortex can result in a focus of hyperexcitable patch of cortex
Wernicke’s encephalopathy
dysfunctions/degeneration in the mammillary bodies
Wernicke’s encephalopathy symptoms
Confusion
Memory loss
Altered mental status
Gate abnormality
Visual hallucinations are typically
toxic. think alcohol or drugs
Auditory hallucinations are
psychotic. think Schizophrenia
dorsolateral prefrontal cortex
goal orientated and self awareness
parietotemporal association
sensory integration, problem solving, understanding language
ventral and medial prefrontal cortex
emotion, motivation and personality
