Midterm 1 Flashcards
What is Plato’s theory of forms?
we can never be sure of what our senses are telling us, we can only be certain of reasoning
What is anamnesis?
- Our immortal souls are made of left-overs of a greater “cosmos-soul” that had universal knowledge
- We lost this knowledge when our souls were incarnated in our imperfect bodies
- We must recover this knowledge by trying to “remember” what we “forgot”
Who is John Locke?
- Empiricist
- Tabula rasa: humans are blank pieces of papers on which experience leaves its mark
- Experience –> simple ideas –> complex ideas
Who is David Hume?
- Empiricist
- Inference of necessary cause and effect (B has to follow A) relationship is invalid, but psychologically we believe there is cause and effect
- Beliefs are caused by psychological “habits”
Who is Immanuel Kant?
Critique of pure reason
- We may never really know the thing-in-itself (Noumenon)
- All we know is the impression that the noumenon exerts on our senses (Phenoumenon)
Who is Thomas Bayes?
- Perception is the process of inferring what’s out there in the world based on the input of our senses
- Sensation is the input; perception is a probabilistic inference that integrates that sensation with our prior knowledge of the world
- At each stage, feedforward information coming from lower levels is merged with inferred knowledge coming from higher levels
What is the just noticeable difference (JND)?
the smallest change in a stimulus that can be detected.
What is discriminability?
How easy it is to notice a small difference in terms of physical intensity
- Higher weber fraction (ex: 0.3) means lower discriminability
- High discriminability = NO NOISE
What is the difference threshold?
The smallest difference you can perceive BETWEEN TWO STIMULI
What is the absolute threshold?
the smallest level of stimulus that can be detected, usually defined as at least half the time
What is noise in perception?
whichever physiological or psychological processes that can influence our perception of that external stimulus in an unpredictable manner
What is the method of constant stimuli?
several intensities are systematically tested in a random order
What is the method of limits?
ascending/descending cycles; change in direction when a “yes” or a “no”
What is the method of adjustment?
let the participant increase/decrease intensity in order to identify the threshold
What is the staircase method?
go back as soon as there is a change in response
What is sensitivity?
the capacity to detect a sensory signal when there is one
What is transduction?
the physical stimulus interacts with a specific receptor located on a peripheral sensory neuron and causes the neuron to fire (the stimulus is transduced into an electrical signal)
What is transmission?
when action potential occurs; sodium enters the cell, depolarizing it to open more voltage-gated sodium channels down the axon
What is a photon?
a quantum of visible light (or other form of electromagnetic radiation) demonstrating both particle and wave properties
What is accomodation?
the process in which the lens changes its shape, thus altering its refractive power
What is the retina?
a light-sensitive membrane in the back of the eye that contains rods and cones
What is a diopter?
Measures the focusing force of the lens
- the reciprocal (1 divided by) of the focal length
What is the focal length?
distance between the lens and the point at which light rays converge (the focus)
What is emmetropia?
the happy condition of no refractive error
