Exam 1 Flashcards
(43 cards)
Sensation vs. Perception
Sensation= the ability to detect a stimulus
vs.
Perception= the act of giving the detected stimulus meaning
Thresholding vs. Scaling
Thresholding= measuring limits of sensitivity; the stimulus that produces an arbitrary, but defined level of performance
vs.
Scaling: ordering a distributing stimuli along a perceptual dimension
Method of Constant Stimuli (Steps on how it works)
1) Choose stimuli of varying intensities
-some that you think people will always be able to perceive
-some that you think people will never be able to perceive
-some stimuli in between
2) Present each stimulis multiple times
3) Record proportion of correct responses for each intensity
Ex: Different shades of circles (L1S18)
Pros & Cons of Method of Constant Stimuli
+ Easy to Administer
-Have to know what the threshold is going to be (approximately) before you start
Method of Limits (Steps on how it works)
1) Start with a stimulus that can be perceived or the opposite
2) If perceivable, lower intensity (opposite: If not perceivable, raise intensity)
3) Continue until stimulus can’t be perceived (or can be perceived)
4) Test multiple times
Ex: Staircase/ “up-down” method (L1S21)
Pros and Cons of Method of Limits
+You don’t need to know where the threshold is at the start
+Robust measure of threshold
-Spurious thresholds may be obtained without evidence that the listener was really doing the task
Method of Adjustment (Steps on how it works)
1) Give subject control of the stimulus intensity
2) Instruct subject to adjust level until they can just not hear the stimulus
3) Test multiple times
Ex: Beskesy’s Tracking Method (L1S29)
Pros and Cons of Method of Adjustment
+Easy/Fast
+Intuitively appealing
-Produces unreliable results
Go No-Go assay for Measuring Thresholds
= measures response inhibition
-participants respond to certain stimuli (‘go” stimuli) and make no response for others (“no-go” stimuli)
Go No-Go assay example (stimulus, response, hit, miss, correct rejection, and false alarm) on “What is the detection threshold for coffee aroma?”
Stimulus: coffee Response: button press
-Hit (correct): Pressing button with a Go-stimulus
-Miss(incorrect): Not pressing button with a Go-stimulus
-Correct Rejection (correct): Not pressing button with a No-Go stimulus
-False Alarm (incorrect): Pressing button with a No-Go stimulus
Two alterative force choice (2AFC) assay for measuring thresholds
=measures the subjective experience of a person or animal through their pattern of choices and response times
Two alterative force choice (2AFC) assay example (stimulus, response, hit, miss, and false alarm) on “What is the detection threshold for coffee aroma?”
Stimulus: coffee
Responses: press white button for can smell vs. press red button for can’t smell
-Hit(correct): when press white button with Stimulus 1(coffee) or when press red button with Stimulus 2(none)
-Miss (incorrect): when doesn’t press white button with Stimulus 1(coffee) or when don’t press red button with Stimulus 2(none)
-False Alarm (incorrect): when press red button with Stimulus 1(coffee) or press white button with Stimulus 2(none)
Signal Detection theory (definition and example)
=theory relating to analysis of decision-making processes in the presence of uncertainty
-Element of risk with every decision, and able to accept you can be wrong
-measuring how sure you have to be before making a decision
ex: merging car lanes
some individuals would insist on 100% certainty while others might decide to squeeze into a spot knowing that there is a chance of getting hit
Why is Signal Detection theory important
It demonstrates how certain you are of your perception
-measuring how sure you have to be before making a decision
Action potential=
when a neuron alters this electrochemical gradient down an axon, away from the cell body
Key ions and their charges
-Sodium (NA+)- 1 positive charge
-Potassium (K+)- 1 positive charge
-Calcium (Ca2+)- 2 positive charges
-Chloride (Cl-)- 1 negative charge
More of ions (inside vs. outside) during resting potential
-More Sodium (NA+) outside the cell
-More Potassium (K+) inside the cell
-More Chlorine (Cl-) outside the cell
-More Calcium (Ca2+) outside the cell
-Amino Acids inside the cell
Resting membrane potential=
the difference of changes, inside and outside the cell
Depolarize vs Hyperpolarize vs Repolarize
Depolarize: LESS negative than before (+ move inside)
vs.
Repolarize: RETURNING back to being negative
vs.
Hyperpolarize: MORE negative than before (- move inside)
a.needs more activation to trigger an action potential
How does Optogenetic stimulation of a light sensitive sodium or chloride channel would influence the neuron/resting membrane potential
Optogenetics is used to either inhibit or activate a neuron
Channelrhodopsin is the sodium ion channel that allows the neuron to become activated because it allows sodium into the cell, depolarizing it and starting an action potential
Halorhodopsin is the chloride ion channel that inhibits the neuron because it allows the flow of chloride into the cell, hyperpolarizing it and making it further from an action potential
The contribution of each ion during an action potential/ neurotransmitter release
Sensory Cranial Nerves functions
1- Olfactory=
2-Optic=
8-Vestibucochlear=
1- Olfactory= smell
2-Optic= vision
8-Vestibucochlear= hearing and balance
Motor nerves functions
3-Oculomotor nerve=
4-Trochlear nerve=
6-Abducens nerve=
11-Spinal accessory nerve=
12-Hypoglossal nerve=
3,4,6= eye muscle
-along with the optic nerve, help with looking around
11-Spinal accessory nerve= neck muscles
12-Hypoglossal nerve= tongue muscles
Cranial nerves (sensory & motor) functions
5-Trigmenial=
7-Facial nerve=
9-Glossopharyngeal=
10-Vagus nerve=
5-Trigmenial= face, jaw muscles
7-Facial nerve= tongue, facial muscles
9-Glossopharyngeal= tongue
10-Vagus nerve= autonomic system (send the signals to cause your heart to beat)
