6 - sensation Flashcards
Nociception are a subtype of the skin, receptor that is involved in
Pain and temperature perception
Mechanoperception, subsystem of the skin, receptor is involved in
Touch perception
Rate coding
Number of AP’s per time unit code for strength of stimulus
Sensory adaptation (principle of sensory system)
Firing rate of neuron decreases as time progresses, even though the stimulus is constant.
Intensity coding (principle of sensory system)
The firing rate of cells increase when a stimulus becomes more intense
Range fractionation (principle of sensory system)
One receptor cannot cover a whole fraction range.
Different type of receptors cover for different stimulus intensity sensitivities (So different light intensity)
Integration
Multiple neuron receptors cover different (e.g. light) intensities. They feed into 1 next neuron which sums it all up and then covers the whole range.
So
- 1 neuron does not cover a whole range
- Multiple are needed to cover and then are combined
Dermatome
Patch of the skin that maps to a specific part in the spine
Top down processing
Can influence what the thalamus communicates to hersenschors about the senses.
It can put emphasis or de-emphasise on e.g. sounds
Decussation
CROSSING OVER OF INFORMATION
Info crosses the midline, coming in on the left ends up in the right (of the medulla)
Controleteral
Other side (contra)
Receptors field of a neuron
Region in sensory space that changes firing rate of neuron
Plasticity
Change of connectivity of mostly cortical neurons, depending on the use of the
The function of range fractionation
Is to neural code both weak and intense stimuli by a single neuron
Piezo2 is an ion channel that opens when …
Stretched
What does the principle of labeled lines mean?
Sensory info sends action potential along separate nerve tracks.
Sensory info is (partly) coded by the connection between receptors and receiving areas in the CNS
Neural adaptation
Decreases firing of neuron as the stimulation continues
What defines the primary sensory cortex
First part of the brain that receives sensory input directly from the thalamus
Neural plasticity in cortical maps
Are changes of mapping of sensory periphery to cortex
(If you lose your hand, the face and the arm take over those neurons bc they are close to the area of the hand in the sensory cortex in the brain)
Some neurons have touch receptors in the skin. Where is their soma located
Dorsal root ganglion
Pain and touch in your lil toe active different receptors cells (pain and touch cells). Which was had the longest axon?
Touch receptor cells
Propresaption
Knowing where your limbs are, the fastest fibres in your body.
Modality
Different types of sensation, so either vision, smell etc.
Which 4 mechanism can open and close ion channels?
1) Light
2) Temperature
3) Voltages
4) Ligand gates
Ganglions
Cluster of somata (nervous cells) in the peripheral nervous system.
Anatomical term
Basal ganglia, in the brain are
Balls of nucleus, consisting of Brain matter
Somatic senses are in the
Skin, mucles and joints
Which sensory information does not go trough the thalamus and is an exception to the rest?
THE OLFACTORY CORTEX, SMELL
Dorsal colum system is involved in
Touch, where info crosses at the medulla
Anterior lateral system/spynal thalamic is involved in
Pain and temperature, where info crosses at the spine (before medulla)
