Intro To Sensory Flashcards
Stimulus processing is usually_____ where is processing is usually____
Conscious And subconscious
What is proprioception
Knowing where your body is in space
Chemo receptors, what might they respond to
Oxygen change, pH change, various organic molecules such as glucose
Give examples of mechanoreceptors
Pressure (BP = baroreceptors), cell stretch (osmoreceptors), vibration, acceleration, sound
Photo receptors respond to
Photons of light
Thermo receptors respond to
Varying degrees of heat
A stimulus is converted into a graded potential via
Sensory transduction
What is sensory transduction
Convert a stimulus into a change in membrane potential
Adequate stimulus
A form of energy to which a sensory receptors most responsive
Receptor potential
A graded potential but it’s in the sensory receptor
Threshold
The minimum stimulus required to activate a receptor
In order for sensory neurons to respond to a stimulus, that stimulus must fall within a specific physical area called
The receptive field which is the area that a stimulus needs to be present to be noticed
Bev to stimulus is our very close together they may
Filter into one neuron and only send one signal to the brain instead of two
True or false? The primary sensory neurons converge on one secondary sensory neuron and information from only one secondary neuron goes to the brain? Can this happen?
True, yes it can
Why is the sensory pathway for olfaction different?
Most sensory pathways go through the thalamus but the old factory pathway starts at the nose goes to the old factory bulb and then to the old factory cortex
What is the function of the thalamus
The salmon is modified some relays information to specific cortical centres or areas of the brain
What does equilibrium effect and where does it’s pathway project to?
It can affect balance so when drinking GABA is increase to the cerebellum which is where equilibrium pathway projects to
What are four important properties of stimuli and define them
Modality: is the nature of the stimuli so each receptor is most responsive to one modality or type of stimulus. Location: which receptive fields are activated. Intensity: determined by the number of receptors activated and the frequency of action potential’s. Duration: how long the receptors are activated
Talk about lateral inhibition and location
Pathway closest to the stimulus inhibits its neighbours To allow for a clear signal going to the brain and enhancement of the perception of the stimulus
What happens if intensity and duration are high
There’s a higher frequency of action potential is generated some more neurotransmitters are being released
Tonic receptors
Slowly adapting receptors that respond for the duration of a stimulus
Phasic receptors
Rapidly adapt to a constant stimulus and turn off
How does adaptation work in tonic receptors
It keeps responding and tends to respond for the whole duration like when you touch something hot. The number of action potentials is constant and the receptor potential doesn’t get back down in the image
How does phasic receptors work with adaptation
They rapidly adapt a constant simulators and turn off so a lot of this would be like when you’re sitting on a chair or your shoes on your feet
Adaptation allows us to?
Filter out extraneous sensory information and focus on what is important
A stimulus above threshold initiates action potential’s in the sensory neuron that projects to the…
Central nervous system
Stimulus intensity and duration are coded in the pattern of action potential’s reaching the…
Central nervous system
Stimulus location in modality are coded according to which
Receptors are activated
Each sensory pathway projects to…
A specific region of the cerebral cortex
What are the four somatic senses
Touch (pressure and vibration) proprioception (determining where we are in space) temperature (thermo receptors) Nociception (pain and itch receptors)
Sensory information is processed on
The opposite side of the brain then the body, crosses over at some point
When does pain, temperature and course touch cross the midline
In the spinal cord
Find touch vibration and pro Praia section pathways cross the midline
In the Medulla
Sensory pathways, at this point secondary sensory neurons, synapse where?
In the thalamus
Sensations are perceived in the
Primary somatic sensory cortex
The amount of space on the somatosensory cortex devoted to each body part is proportional to
The sensitivity to that part so there are large area is devoted to the hands and face and they have come out with things called sensory homunculus
