Lectures 3 & 4 (test 1) Flashcards
(71 cards)
magnitude estimation
- power law
- scaling approach where subjects provide direct ratings of their sensation
Stevens Power Law
S = k * l^b
sensory transducer theory
the idea that transduction of the physical stimulus into a biological stimulus is the basis of the power-law
intra-modal matching
- a scaling technique
- comparing different aspects of a stimulus within a particular sensory modality
cross-modal matching
- compare stimuli from one sensory modality to stimuli of another modality
The absolute threshold can vary because…
- stimulus variation
- cognitive factors
- nervous system variability
- noise in biological system
4 possible outcomes of SDT
- hit
- miss
- correct rejection
- false alarm
hit
yes signal
yes response
miss
yes signal
no response
false alarm
no signal
yes response
correct rejection
no signal
no response
conservative criterion
tell them to expect 30% of time
liberal criterion
tell them to expect 70% of time
the large the d’
higher the sensitivity
receiver operating characteristics (ROC) curve
- plots hit vs false alarms
- provides estimates of d’
does a true threshold exist?
we cannot say it does
ROC straight line
50% hit / miss rate
d’ =0’
cannot detect sound over noise
d’=3
means almost 100% hit rate
Charles Darwin theory of evolution
suggests continuity in the structure and function of the senses and nervous system
Johannes Müller Doctrine of specific nerve energies
not aware of world around us, only aware of nerve activity
Hermann Von Helmholtz
first to successfully measure neurons transmission speed
Santiago Ramón y Cajal Neuron Doctrine
detailed neuron drawings of neurons and how hey never touch
Sir Charles Sherrington
coined term “synapse”
