Limbic System Flashcards
What are the four categories of limbic system functions?
Olfaction
Memory
Emotions and drives
Homeostasis
Structure responsible for olfaction
Olfactory cortex
Structure responsible for memory
Hippocampal formation
Structure responsible for emotions and drives
Amygdala
Structures responsible for homeostasis
Hypothalamus
What are the parts of the limbic system?
Limbic cortex (limbic lobe)
Hippocampal formation
Amygdala
The limbic cortex is made up of ….. (3)
Cingulate gyrus
Parahippocampal gyrus (includes uncus)
Septal area (includes subcallosal gyrus)
The hippocampal formation is made of what type of cortex? How many layers does it have?
Archicortex
3 layers
The olfactory cortex is made up of what type of cortex? How many layers does it have?
Paleocortex
3 to 5 layers
The neocortex has ___ layers and makes up ___% of the human cerebral cortex
6 layers
90%
The olfactory system is made up of what 3 parts?
Olfactory nerve
Olfactory bulb
Olfactory cortex
The olfactory bulb contains
Mitral and tufted cells
The olfactory cortex contains
Piriform and periamygdaloid cortex
What is the function of the hippocampal formation?
Formation of new memories and learning
Declarative memory vs nondeclarative memory
Declarative: conscious recollection of facts or experiences
Nondeclarative: nonconscious learning of skills, habits and other acquired behaviors
What occurs with memory during amnesia?
Declarative memory loss (cannot memorize new events well), nondeclarative memory stays intact
Declarative memory includes
Facts, events
Nondeclarative memory includes
Skills and habits
Priming
Simple classical conditioning
Nonassociative learning
What is retrograde amnesia?
Lose memories of past
What is anterograde amnesia?
Cannot form new memories even as soon as past 5 minutes
Damage to the hippocampal formation leads to
Profound anterograde amnesia, nondeclarative memory is unaffected
What are the parts of the hippocampal formation?
Dentate gyrus
Hippocampus
Subiculum
What are the symptoms of Alzheimer’s?
Lose LTM (anterograde amnesia, cannot learn new facts or events)
Abnormalities with cognition, orientation, behavior
Pathology of Alzheimer’s
Neurons in the hippocampal formation and parahippocampal gyrus degenerate
What are the symptoms of Korsakoff syndrome?
Lose long term memory (anterograde amnesia)
Tendency to fabricate false accounts of recent events
What is the pathology of Korsakoff syndrome
Neurons in medial dorsal nucleus of thalamus, hippocampal formation, mammilary nuclei (hypothalamus)
Korsakoff syndrome is typically due to
Chronic alcoholism, nutritional deficiencies such as thiamine deficiency
The main function of the amygdala is ….
The amygdala is also an active participant in ….
Emotions and drives
All four limbic system functions
What are the symptoms of Kluver-Bucy syndrome?
Placid behavior, decreased emotions, hyperattentive, hypersexual, visual agnosia
What is the pathology of Kluver-Bucy Syndrome?
Bilateral lesion of amygdaloid complex
What is the septal area of the brain? What is its function?
Portion just anterior and inferior to the corpus callosum
Function is to organize addictive behavior, act as reward or pleasure center input from hippocampus
The septal area has reciprocal connections with …
Amygdala
Hypothalamus
Cingulate gyrus of limbic cortex
What are the 3 subdivisions or zones of the hypothalamus?
Periventricular (light shading)
Medial (darker solid shading)
Lateral (Patterned shading)
What are the four regions of the hypothalamus?
Preoptic area (anterior)
Supraoptic (anterior)
Tuberal (middle)
Mammilary (posterior)
What are the symptoms of hypothalamic syndrome?
Diabetes insipidus
Endocrine imbalance
Impairment of temperature regulation
Abnormalities of sleep patterns
Behavioral changes
What is the pathology of hypothalamic syndrome?
Lesion of hypothalamus
