Sensorimotor System Flashcards
all animals have sensory organs containing … that sense some stimuli, but not others
- different kinds of sensory modalities require different sensory organs to convert them into neural activity
receptor cells
sensory organs are very diverse, but all senses have the same end point:
they convert the info they receive into electrical signals (or, action potentials)
the brain recognizes the senses as distinct because their action potentials travel along separate nerve tracts
labeled lines
- because each receptor cell sends a signal on a particular “line” the brain “knows” what sort of touch happened
the … of a receptor cell determines what kind of energy or chemical to which it will respond
structure
when the stimulus binds or a receptor is activated, it makes a … - a local change in membrane potential
generator potential
this conversion of energy from a stimulus into a change in membrane potential in a receptor cell is called…
sensory transduction
the … is a skin receptor that responds to vibration and pressure, detecting textures
Pacinian Corpuscle
- a stimulus to the corpuscle opens sodium channels and produces a graded generator potential
if the potential exceeds the firing …, an action potential is generated
threshold
- only if the action potential is generated do you detect the touch
respond to changes in stimuli
Meissner’s Corpuscles
respond to edges and isolated points
Merkel’s Discs
detect stretching of the skin when we move fingers or limbs
Ruffini Corpuscles
free …. in the skin respond to pain, heat and cold
nerve endings
the nervous system uses labeled lines to identify …
the types of stimulus
the action potentials produced by a sensory neuron always have the same size and duration, so one way the intensity of sensory events are encoded is in … and … of action potentials
number and frequency
the … can determine whether body sensations arise from outside or within the body
somatosensory system
