Neuroanatomy Flashcards
Gray matter
Consists of unmyelinated neurons and contains capillaries, glial cells, cell bodies and dendrites
White matter
Consists of myelinated axons and contains nerve fibers without dendrites
Forebrain (prosencephalon)
Telencephalon and diencephalon
Telencephalon
Cerebrum, hippocampus, basal ganglia, amygdala
Diencephalon
Thalamus, hypothalamus, sub thalamus, epithalamus
Midbrain (mesencephalon)
Tectum and tegmentum
Tectum
Superior and inferior colliculi
Tegmentum
Cerebral aqueduct, periaqueductal gray, reticular formation, substantia Nigra, red nucleus
Hindbrain (rhombencephalon)
Metencephalon, myelenceophalon
Metencephalon
Cerebellum, pons
Myelenceophalon
Medulla oblongata
Brainstem
Midbrain, pons, medulla oblongata
Sympathetic nervous system
Prepares body for emergency response
Norepinephrine
Parasympathetic nervous system
Conserving and restoring energy
Acetylcholine
Limbic system
Made up of: corpus callosum, olfactory tract, mammillary bodies, fornix, thalamus nuclei, amygdala, hippocampus, parahippocampal gyrus, cingulate gyrus, hypothalamic nuclei
Involved in the control and expression of mood and emotion, processing and storage of recent memory, olfaction, control of appetite, and emotional responses to food
Lesions can result in aggression, extreme fearfulness, altered sexual behavior and changes in motivation
Inter hemispheric fissure (medial longitudinal)
Separates two cerebral hemispheres
Sylvian fissure (lateral)
Anterior portion separates the temporal and frontal lobes
Posterior portion separates temporal and parietal lobes
Central sulcus (sulcus of Rolando)
Separates frontal and parietal lobes laterally
Parietal occipital sulcus
Separates parietal and occipital lobes medially
Calcarine sulcus
Separates occipital lobe into superior and inferior halves
Left hemisphere
Language Sequence and perform movements Understand language Produce written and spoken language Analytical/Controlled Logical/rational Mathmatical calculations Express positive emotions such as love and happiness Process verbally codes information in an organized, logical and sequential manner
Right hemisphere
Nonverbal processing Process info in holistic manner Artistic abilities General concept comprehension Hand eye coordination Spatial relationships Kinesthetic awareness Understand music Understand nonverbal communication Mathematical reasoning Express negative emotions Body image awareness
Frontal lobe function
Voluntary movement (primary motor cortex and pre central gyrus)
Intellect and orientation
Broca’s area (typically left): speech, concentration
Personality, temper, judgement, reasoning, behavior, self awareness, executive functions
Frontal lobe impairment
Contra lateral weakness Perseveration, Inattention Personality changes, antisocial behavior Impaired concentration, apathy Brocas aphasia (expressive) Delayed or poor initiation Emotional lability
Parietal function
Associates with sensation of touch, kinesthesia, perception of vibration, and temperature
Receives info from other areas of brain regarding hearing, vision, motor, sensory and memory
Provides meaning for objects
Interprets language and words
Spatial and visual perception
Parietal lobe impairment
Dominant hemisphere: typically left: agraphia, alexia, agnosia
Non dominant hemisphere: typically right: dressing apraxia, constructional apraxia, anosognosia
Contra lateral sensory deficits
Impaired language comprehension
Impaired taste
Temporal function
Primary auditory processing and olfaction Wernickes area (typically left): ability to understand and produce meaningful speech, verbal and General memory, assists with understanding language Rear of temporal lobe enables humans to interpret other people's emotions and reactions
Temporal lobe impairment
Learning deficits Wernickes aphasia: receptive Antisocial, aggressive behaviors Difficulty with facial recognition Difficulty with memory, memory loss Inability to categorize objects
Occipital lobe function
Main processing center for visual information
Processes visual information regarding colors, light and shapes
Judgement of distance, seeing in three dimensions
Occipital lobe impairment
Homonymous hemianopsia
Impaired extra ocular muscle movement and visual deficits
Impaired color recognition
Reading and writing impairment
Cortical blindness with bilateral lobe involvement
Hippocampus
Deeply embedded in temporal lobe
Forms and stores new memories of ones personal history and other declarative memory
Learning language
Sends memories to appropriate areas of hemispheres for long term storage and retrieves when needed
Basal ganglia
Gray matter masses deep within white matter of cerebrum
Includes caudate, putamen, globus pallidus, substantia Nigra, subthalamaic nuclei
Responsible for voluntary movement, regulation of autonomic movement, posture, muscle tone and control of motor responses
Disorders linked: Parkinson’s, huntingtons, Tourette’s, ADD, OCD and addiction
Amygdala
Small almond shaped nuclei in temporal lobes of each hemisphere. Emotional and social processing. Involved with fear and pleasure responses, arousal, processing of memory, and formation of emotional memories
Thalamus
Relay or processing station for majority of info going to cerebral cortex
Coordinates sensory perception and movement with other parts of the brain and spinal cord
Hypothalamus
Receives and integrates info from autonomic nervous system, assists in regulating hormones. Controls hunger, thirst, sexual behavior and sleeping. Regulates body temperature, adrenal glands, pituitary gland, and other vital activities.
Sub thalamus
Primarily represented by the subthalamaic nucleus. Regulates movements produced by the skeletal muscles. Has association with basal ganglia and substantia Nigra
Epithalamus
Pineal gland
Secretes melatonin and is involved in circadian rhythms, internal clock, selected regulation of motor pathways and emotions. Associated with limb if system and basal ganglia
Pons
Regulation of respiration rate and orientation of head in relation to visual and auditory stimuli. Cranial nerves 5-8 originate from the pons
Medulla oblongata
Influences autonomic nervous activity and regulation of respiration and heart rate. Reflex centers for vomiting, coughing, and sneezing
Somatic sensory info from internal organs and for control of arousal and sleep
Cranial nerves 9-12 originate here
Axon
Projection of nerve away from cell body that conducts impulses
Dendrite
Extension of cell body that received signals from other neurons
Endoneurium
Innermost covering of a peripheral nerve that surrounds each individual axon
Epineurium
Outermost covering of peripheral nerve that surrounds entire nerve and provides buffer for peripheral nerve
Motor unit
Single motor neuron and all of the muscle fibers that it innervates
Myelin
Proteins and lipids that form to create a sheath around particular nerves, increases conductivity of nerve impulse
Nerve conduction velocity
Measures speed of a nerve impulse along axon of a nerve
Neurons
Nerve cells that receive and send signals to other nerve cells. Comprised of cell body, axon and dendrites
Nodes of ranvier
Brief gaps in myelination of an axon, serves to facilitate rapid conduction of a nerve impulse via jumping from gap node to gap node
Perineurium
Middle layer of covering surrounding peripheral nerve that envelopes fascicles or groups of axons and maintains blood nerve barrier
Saltatory conduction
Action potential moving along an axon in a jumping fashion from node to node; decreases use of sodium potassium pumps and increases speed of conduction
Schwann cell
Cells that cover nerve fibers within peripheral nervous system and form myelin sheath
A fibers
- large fibers, myelinated, high conduction rate
- alpha beta, gamma, delta subsets
Alpha fibers
Alpha motor neurons, ms spindles primary endings, Golgi tendon organs, touch
Beta fibers
Touch, kinesthesia, ms spindle 2’ endings
Gamma fibers
Touch, pressure, gamma motor neurons
Delta fibers
Pain, touch, pressure, temperature
Ms spindle (primary afferent endings)
Primary for low-threshold stretch
Ms spindle (2’ afferent endings)
Receptors that respond to changes in length
Golgi tendon organ
Responds to tension/stretch of tendon
B fibers
Medium fibers, myelinated, reasonably fast conduction rate, pre-ganglionic fibers of autonomic system
C fibers
Small fibers, poorly myelinated or un-myelinated; slow conduction rate; post-ganglionic fibers of SNS; exteroceptors for pain, temp, & touch
