Day 1 lecture: Neurology Flashcards
Special Senses (4)
Hearing, smell, vision, Taste
Where is the motor cortex located?
pre central gyrus on the Frontal lobe
This is the relay center of sensation to the cortex and other brain area.
Thalamus
Examples of when spinal cord is controlling sensory input causing appropriate motor output. (2)
- Spinal reflex 2. Micturition reflex
Membrane depolarization by an action potential causes emptying of a small number of vesicles into the synaptic cleft which ____ or ____ the postsynaptic neuron.
excites: EPSP (excitatory postsynaptic potential) … inhibits: IPSP (inhibitory postsynaptic potential)
Dopamine has highest concentration in the ___.
substantia nigra
They act as modified post ganglia in the adrenal medulla, releasing Epi and NE.
Chromaffin cells
Part of the brain that contains the neuron cell bodies.
Gray Matter
This is the main body of the neuron (contains cell’s nucleus)
Soma
Two factors that cause “neuronal fuse” or fatigue of synaptic transmission.
- Post membrane receptor inactivation 2. Inability to maintain necessary ionic concentration differences at the post synaptic membrane for Ca influx.
How many neuron pathways are there in the ANS (PNS and SNS)?
2 neuron pathways from CNS to effector
Organization of Nervous System: It is the connection of sensory and motor divisions. It processes info, creates desired response and creation of memory.
Integrative division
Lower Brain level or Subcortical level includes the ____ (7)
- Hypothalamus 2. Thalamus 3. Cerebellum 4. Basal ganglia 5. Medulla 6. Pons 7. Mesencephalon
This type of neurotransmitters are more potent than small molecule transmitters, and can cause more prolonged actions.
Neuropeptides
Part of motor neuron where signals are added up.
Axon Hillock
Soma is composed of (2)
Chromatophilic (Nissi) bodies Neurofibrils
Somatic sensory cortex is located in the ________ area of the brain.
post central gyrus
In Somatic sensory cortex: It has the least area of representation.
trunk and lower body
This is part of the activating system that is involved in deciding whether or not a sensory info should go to the conscious level (cortical level).
Reticular substance/ Reticular formation
The second most prevalent neurotransmitter.
Gamma- aminobutyric acid
How long is the synaptic delay?
0.5 millisec
True or False: Cortex never functions alone, always in association with lower centers.
true
The pre-ganglionic autonomic neuron always releases this neurotransmitter.
ACh
What type of neuron is present at the Integrative division of the nervous system?
Interneuron
Name 7 subconscious body activities controlled by subcortical level.
- CV control 2. Respiration 3. Equilibrium 4. Emotional patterns 5. Feeding reflexes (hunger/ thirst)
The cortex consists of _____, each of which has a different composition in terms of neurons and connectivity.
up to 6 horizontal layers.
It includes skin senses, proprioception, and info from internal organs. Other name for somatosensory.
Somesthetic (somatosensory)
Skeletal muscle can be controlled at any of these (5) levels.
- Spinal Cord 2. Reticular Substance/ reticular formation 3. Basal ganglia 4. Cerebellum 5. Motor cortex (pre-central gyrus)
Length of synaptic cleft
20 NM
Type of synapse: Characterized by direct open fluid channels that, through GAP junctions, allow free movement of ions from one cell to the next.
Electrical synapse
How many neuron pathways are there in somatic (skeletal) nervous system?
1
The spinal cord contains intrinsic neural pathways, known as ____, for repetitive limb movements (e.g. walking, swimming, etc.. )
Central pattern generators (CPG)
This substance is released from the vesicles and acts upon receptor proteins on the membrane of the cell to which the information is being transmitted.
Neurotransmitter.
Each side of the somatic sensory cortex receives information from the _______ of the body.
opposite side (contralateral)
Loss of somatic association areas results in ___ (2)
- inability to recognize complex objects 2. loss of self (alien arm syndrome)
3 Major components of a Motor Neuron
- Soma (cell body) 2. Axon 3. Dendrites
Nitric oxide (NO) alters ___ that will modify excitability of the postsynaptic neuron.
metabolic function
These are intermediate protein filaments that hold the cell together.
Neurofibrils
How many synapses are found in white matter or fiber tract?
NONE. Synapses are only found in GREY MATTER!!!
How many molecules have been identified as neurotransmitters?
50
It’s function is to decipher sensory meaning.
Somatic association area.
The somatic association area receives input from ___ (3)
- Somatosensory cortex 2. Thalamus 3. Visual and auditory cortex
How many percent of sensory info is discarded by brain as unimportant and irrelevant.
99%
A neuron can have how many terminal branches (or synapses)?
10,000/ neuron
True or false: Chemical synapse is a one way conduction (pre to post synaptic neuron)
True
How thick is the cerebral cortex?
2 - 4 MILLIMETER
The cell bodies of somatic motor neurons reside in the ____.
ventral horn of the spinal cord.
3 Major levels of CNS Function
- Spinal cord level 2. Subcortical level or lower brain level 3. Cortical level or Higher brain Level
This is a single process that extends from the cell body to the terminus; conveys impulse AWAY from cell body.
Axon
In Somatic sensory cortex: It has the greatest area of representation.
Lips and hands
This is the most prevalent neurotransmitter.
Glutamate
Local circuits in the spinal cord are fully capable of: (2)
- controlling time and coordination of complex patterns of movements. 2. Adjusting them in response to altered circumstances.
Circuits for breathing, chewing, and swallowing are located in the ______, whereas those for locomotive functions are contained in the ______.
brain stem …….. spinal cord
These are many processes that carry impulses TOWARD the cell body.
Dendrites
This is thought to be involved in planning what and when muscles are activated.
Basal ganglia
It contains cell bodies of neurons.
Nucleus
Serotonin: Neurons that originate in ______ to terminate in dorsal horns of cord and hypothalamus
median raphe of brain stem.
Organization of the Nervous System: It conveys AFFERENT nerve impulses to CNS.
Sensory Division
The post central gyrus (somatosensory area) is located in which brain lobe?
Parietal area of the cortex
5 different nuclei that make up the basal ganglia. (Paired)
Putamen Globus Pallidus Caudate Subthalamic Substantia Nigra
This enzyme is an integral membrane glycoprotein that is restricted to the apical plasma membrane of the follicular epithelial cells.
Thyroid peroxidase
Electrical synapses can be found in __ (2)
smooth and cardiac muscles
How is information communicated between neurons?
Synapses
Organization of Nervous System: It conveys efferent impulses to effectors.
Motor Division
This neurotransmitter is secreted at locations associated with long term behavior and memory.
Nitric oxide (not-preformed or stored; created instantaneously)
3 functions of basal ganglia
- Voluntary motor control 2. Procedural learning (motor skills) relating to routine behaviors or “habits” 3. action selection
True or False: Somatic sensory cortex has highly organized distinct spatial orientation.
True
Type of neuron. These are the most of the body’ sensory neurons. The dendrites are found at the receptor.
Unipolar
This is the depletion of neurotransmitter stores.
Fatigue of synaptic transmission or “Neuronal fuse”
Sensory information go to the primary sensory cortex and some has collateral pathway to the ____.
Cerebellum (involved in muscle movement coordination)
This is an inborn or intrinsic somatic (skeletal muscle response) reflexes mediated by control center in the spinal cord; it sometimes require the participation of higher brain center.
Spinal reflex
NT: It inhibits pain pathways, regulates mood and perhaps associated with sleep.
Serotonin
It is more than just a conduit for signals from periphery of body to brain and vice versa. It contains intrinsic neural pathway.
Spinal Cord (level)
This is the antagonist for GLYCINE, which means it binds to the same receptor thus blocking the INHIBITORY potential of glycine.
Strychnine (stimulant in low doses)
Caudate and putamen are collectively called as ___.
striatum
True or False: Patients with lesions of basal ganglia have movement disorders.
True
The lower brain level or subcortical level controls the ____.
subconscious body activities.
Two types of synapses?
- Electrical 2. Chemical
These are rough ER and loose ribosomes that replenish plasma membrane proteins.
Chromatophilic (Nissi) bodies
One cubic millimeter of cerebral cortex contains how many synapses?
1 billion (total in brain: 100 Trillion).
Type of neuron found as motor and interneurons.
Multipolar
Sensory input can be integrated at any of these (5) levels
- Spinal cord 2. Reticular substance / reticular formation 3. Cerebellum 4. Thalamus 5. Cerebral cortex (somatosensory area)
These are the principal cortical components of a family of parallel circuits linking the thalamus with the cerebral cortex.
Basal ganglia aka Basal Nuclei
Precursor of serotonin
5-hydroxytryptophan
This Neurotransmitter is secreted by many sensory pathways in the cerebral cortex.
Glutamate
Functions of Cortical Level (3)
- Memory 2. Thought processes 3. Open the world up for one’s mind.
Area for consciousness of what we are doing.
Higher brain or cortical level
These are the “bouton” endings of the axon branches.
axon terminals
Type of neuron found only in ear (organ of corti) and eye (retina)
Bipolar (only for hearing and seeing)
This is a way to represent (“mapping”) the amount of cerebral cortex dedicated to specific areas of the body.
Cortical Homunculus
General Sensation or somatic sensory (4)
Pain, pressure, touch, temperature
Part of the brain that contains the fiber tracts or axon processes.
White Matter (White color due to myelination of the axons)
Cell bodies (soma) are located at the ____.
dorsal root ganglia
