Control of Movement Flashcards
Muscle stretch causes activation of Ia spindle afferents.
What happens next?
The afferents make monosynaptic connections with alpha motor neurons innervating the same muscle.
This causes contraction.
Via what structure do sensory afferents enter the spinal cord?
Dorsal root
Via what structure do motor neurons leave the spinal cord?
Ventral root
What do alpha motor neurons release at the neuromuscular junction?
Acetylcholine
A motor neuron and all of the fibres it innervates is known as ….
A motor unit
Role of golgi tendon organ?
Signals the force of muscle contraction
Golgi tendon reflex =
Ib afferents contact Ib inhibitory interneurons.
An increase in muscle force causes a reflex inhibition of the same muscle.
Protects muscle from excessive contraction.
Which mechanoreceptor detects ‘microslips’ in precision lifting, causing a reflex increase in grip force ?
Meissner’s corpuscles
Upper motor cortical lesions cause …
Increased reflex tone
because upper motor neurons have an inhibitory effect