Neuroanatomy Flashcards
Sensory neurons
Carry messages from sensory organs (eyes, ears, skin, etc.) to CNS
CNS + PNS
CNS –> Central Nervous System
PNS –> Peripheral Nervous System
Motor Neurons
Carry messages from motor cortex to voluntary muscle fibers
In the brain:
- Dorsal
- Ventral
- Rostral
- Caudal
- Medial
- Superior - up
- Inferior - down
- Anterior - front
- Posterior - back
- Midline
In spinal cord/brain stem:
- Dorsal
- Ventral
- Back
- Front
Parts of brainstem
Medulla, Pons, Reticular formation
Medulla
Heartrate, blood pressure, respiration
Pons
Sleeping & dreaming, breathing, arousal
Reticular formation
Consiousness, gating of incoming sensory information
Cerebellum
Important for fine motor coordination, learning and memory
Regulates movements requiring precise timing
Midbrain
Considered part of the brain stem
Contains important brain regions (nuclei) for motor planning and execution
Thalamus
Classically kown as the “switchboard” of the CNS
Relays incoming signals from sensory neurons to correspondingareas of the brain (mostly in cerebrum)
Hypothalamus
Role in motivation and emotion
Controls the secretion of hormones into the bloodstream via the pituitary gland
Pituitary gland
Brain’s portal to the neuroendocrine system
Releases hormones that regulate other glands
Hormones regulate sexual behavior, metabolism, stress response, pleasure, pain
Hippocampus
Part of the limbic system
Critical for:
- Memory encoding and retrieval
- Spatial orientation
- Contextual mapping
Amygdala
Part of the limbic system
Motivational and emotional response to environmental stressors
Agression and fear
Corpus callosum
A region containing “white matter” fibers connecting the two cerebral hemispheres
Dissection/agenesis leads to “split brain syndrome”
Gyrus and Sulcus
The gyri are the ridges and sulci are the grooves that appear on the wrinkled surface of the brain
Four lobes
- Frontal lobe
- Parietal lobe
- Occipital lobe
- Temporal lobe
Association areas
Areas that, when stimulated, do not cause sensory or motor reactions
General idea association areas
Process assocations (relationships) between one (unimodal) or multiple (multimodal) sensory and/or motor representations
Grey matter
Contains the somata (cell bodies) of neurons
White matter
Contains the axonal projections of neurons
Soma
The neuronal cell body, containing its nucleas and essential organelles
Dendrites
Specialized receiving units that collect messages from neighboring neurons and send them to the cell body
Axon
Conducts electrical impulses from the soma to distal target regions such as other neurons or muscle cells
Myelin sheath
A layer of fatty tissue that surrounds and insulates the axon, improving its transmission efficiency
Axon terminals
End points of the axon, where electrical impulses typically release chemical signals
Sensory areas Cerebral cortex
- Somatic sensory cortex –> body sensations
- Pimary auditory cortex –> surrounded by higer-order auditory cortex (hearing)
- Primary visual cortex –> surrounded by higer-order visual cortex (sight)
Motor areas cerebral cortex
Primary motor cortex –> voluntary movement
