Receptors
Respond the entire time a stimulus is present
Tonic Receptors
Have two branches: One that connects to the receptor distally and one that goes into the spinal cord
Pseudounipolar neurons/ Sensory Neurons
Area of skin served by one afferent neuron
Receptive Field
Large musculoskeletal afferents
Type I and II
Somato sensory pathway is also known as
Dorsal Column Medial Lemniscus
Electrical change caused by a sensory input in the receptor
Receptor Potential
Peripheral nerves are classified based on 3 attributes. They are
Axon size, Myelination, and type of sensation carried
______receptive fields= better localization
______receptive fields=less precise localization
Small
Large
small musculo skeletal afferents
Type III and IV
Ventero/Ventral Postero Lateral Nucleus
Pain receptor
Free nerve endings
Carries touch, pressure, vibration, stretch (PTVS). They are large.
Mechanical Fibres
Although they are not proprioceptors, they do contribute to body awareness
cutaneous receptors
Two types of efferent nerves that supply the skeletal muscle and muscle spindle
Alpha motor neuron and Gamma Motor Neuron
A cylinderical bundle of sensory fibres that carry information from the lower part of the body and run medially in the dorsal column
Fasciculus Gracilus
Biological transducers that convert mechanical, chemical, and thermal stimuli into electrochemical signals.
Receptors
Carry Mechanical, thermal, and chemical input. Many are nociceptors
Polymodal Fibres
A patient reports numbness and tingling in the thumb, index finger, middle finger, and part of the ring finger. Symptoms worsen at night and after prolonged typing. Grip is mostly intact, but the patient has difficulty with thumb opposition.
median nerve compression, showing a peripheral nerve distribution
Nuclear bag and nuclear chain fibres
Two types of intrafusal fibres
Balance better with eyes open
Positive Romberg's sign- Sensory Ataxia
Stop or reduce firing even while the stimulus is still present
Phasic Receptors
cutaneous afferents from largest to smallest
Aβ,
Aδ
C (No myelin)
Peripheral nerve and dermatome patterns are similar in which region?
Recovery after peripheral nerve damage follows this order
Reticular formation