Sensory Systems Flashcards
Perception of external stimuli is called…
…exteroception
Perception of internal stimuli is called…
…interoception
Classification of senses by the physical nature of their sensitivities:
- photoreception
- mechanoreception
- chemoreception
- thermoreception
- nocireception
- equilibrioception
Approximate number of rods and cones in the eye?
Ca. 100 million rods, and ca. 5 million cones
The optic nerve is formed from the axons of these cells:
retinal ganglion cells
The 5 stages withing the visual pathway:
- Photoreceptors (rods & cones)
- Retinal bipolar interneurones
- Retinal ganglion cells
- Lateral geniculate nucleus of the thalamus
- Primary visual area of the neocortex
The cochlea belongs to which sensory system?
The auditory system
Compartments of the ‘cochlear?’ tube:
- scala vestibuli
- cochlear duct
- scala tympani
The cochlear duct is filled with…
….endolymph
The scala vestibuli and the scala tympani are filled with…
…perilymph
Sensory cells are found on the basilar membrane, which is in…
…the organ of Corti
Approximately how many hair cells do we have?
Ca. 20 thousand
The axons of these nerves form the auditory (vestibulocochlear) nerve proper
Spiral ganglia - clusters of bipolar cells connected to the hair cells
The 5 stages of the auditory pathway:
- Hair cells
- Spiral ganglion cells
- Several nuclei in the lower brainstem
- Medial geniculate nucleus of the thalamus
- Primary auditory area of the neocortex
The two kinds of head movement sensed by the vestibular system:
- rotational
- linear
3-D detection of movement is possible thanks to the:
semicircular system - a system of three semicircular canals perpendicular to one another
Movement of the hair cells in the vestibular system stimulates these cells:
- vestibular ganglia
Some projections of the vestibular system reach the neocortex via…
…the thalamus
The olfactory system is directly connected to…
…the olfactory bulbs
Approximately how many olfactory cells do we have?
Ca. 40 million
The five basic chemoreceptor types in the gustatory system are sensitive to:
sweet, salty, sour, bitter, umami
Stages in the gustatory pathway:
- taste cells in taste buds
- cranial nerve ganglia
- brainstem gustatory nuclei
- thalamus (ventral posterior nucleus)
- insular cortex
The ‘map’ of our body made up of cortical images in the neocortex is called…
…homunculus
The somatosensory system collects signals from our body about…
touch, pressure, temperature, movement, and pain
