Biological Correlates of Psychology Flashcards
If you see these 3 answers on the MCAT and had to make a guess, which should you choose?
a) genetics
b) environment
c) genetics and environment
c) genetics and environment
What is psychophysics?
study of physical stimuli and the sensations and perceptions they produce
What is transduction?
conversion of chemical or physical signals into a cellular response
What is perception?
interpretation and cognition of stimulus info that reaches the brain
TRUE or FALSE: Sensation involves both physiological and mental processing.
FALSE –> sensation involves physical processing ONLY (perception involves physiological and mental)
What occurs during sensory adaptation?
we become less sensitive to a stimulus through constant exposure
What is the “absolute threshold” in terms of a stimulus?
the lowest intensity of a stimulus that can be detected, both physiologically and mentally
TRUE or FALSE: The absolute threshold of a given stimulus varies for different individuals.
TRUE –> we are more/less likely to notice a stimulus based on expectations, previous experiences, familiarity, etc.
What is the “difference threshold” in terms of a stimulus? What is another name for this threshold?
smallest difference between 2 stimulus intensities that is needed for us to recognize a change, 50% of the time
also known as: just noticeable difference (JND)
What is Weber’s Law?
the change required to meet the difference threshold is a constant fraction (the Weber fraction), and the amount of change needed to reach this threshold depends on the original stimulus
delta I / I = k (note: I = intensity, k = constant)
TRUE or FALSE: Weber’s Law differs with the different senses (hearing, seeing, tasting, etc.).
TRUE –> each sense organ has a different sensitivity
What does signal detection theory measure?
ability to differentiate between signals (important stimuli) and noise (unimportant stimuli)
If a signal was present, and an individual responds with “yes, it was present”, what is the term for this signal response?
Hit
If a signal was present, and an individual responds with “no, it was not present”, what is the term for this signal response?
miss
If a signal was not present, and an individual responds with “yes, it was present”, what is the term for this signal response?
false alarm
If a signal was not present, and an individual responds with “no, it was not present”, what is the term for this signal response?
correct rejection
While sensation involves detecting stimuli, _____________ involves selecting which detected stimuli will be further processed.
(Fill in the blank.)`
attention
What is the difference between selective attention and divided attention?
selective attention: focus on solely one stimulus at a time
divided attention: split attention amongst multiple resources at one time
What is the disadvantage of selective attention?
potentially important stimuli can be ignored
What is the disadvantage of divided attention?
may be difficult to allocate enough attention to each stimulus
Explain the dichotic listening task and how it was used to study theories of attention.
different messages played into different ears; subject asked to repeat back the message from one ear and ignore the message from the other, or repeat both messages
Name the 3 theories of attention.
- Broadbent’s Early Selection Theory
- Deutch and Deutch’s Late Selection Theory
- Treisman’s Attenuation Theory
Explain Broadbent’s Early Selection Theory. Write out a flow chart to help explain.
all inputs from the environment first enter a sensory buffer, and then enter a selective filter where some info gets discarded
input –> sensory buffer –> filtering (x) –> perceptual meaning –> short term memory
(note: (x) marks where some info gets discarded)
Explain Deutch and Deutch’s Late Selection Theory. Write out a flow chart to help explain.
selective filtering of incoming inputs occurs AFTER perceptual processing (i.e. all info is perceptually processed, and then we selectively filter info and pass onto conscious awareness)
input –> sensory buffer –> perceptual meaning –> filtering (x) –> short term memory
(note: (x) marks where some info gets discarded)
Explain Treisman’s Attenuation Theory. Write out a flow chart to help explain.
we have an attenuator which weakens incoming info signal (i.e. all info gets to perceptual processing, we assign different levels of priority –> ONLY HIGH PRIORITY info makes it to conscious processing)
input –> sensory buffer –> attenuator (x) –> perceptual meaning –> short term memory
(note: (x) marks where LOW PRIORITY information signals are WEAKENED)
What is inattentional/perceptual blindness?
our ATTENTION IS DIRECTED ELSEWHERE in a visual field and we aren’t aware of certain objects in other areas of our visual field
What is change blindness?
failure to notice changes in immediate visual environment
What is the difference between distal stimulus and proximal stimulus?
DISTAL stimulus: stimulus in the real world (objects/events that sensory receptors respond to)
PROXIMAL stimulus: stimulus that occurs when sensory receptors are activated (activity that results within your brain)
Weber’s Law states:
a) the strength of a sensation grows a the strength of a stimulus increases
b) the stronger the stimulus, the more the stimulus needs to be increased before one notices an increase in the stimulus intensity
c) an increase in the stimulus intensity is more accurately noticed when one is optimally aroused
d) the weaker the stimulus, the more the stimulus needs to be increased before one notices an increase in the stimulus intensity
b) the stronger the stimulus, the more the stimulus needs to be increased before one notices an increase in the stimulus intensity
explanation:
Weber’s law states that the change required to meet the difference threshold is a constant fraction of the original stimulus. E.g. the brighter the light, the higher the difference in brightness we need for this difference to be perceived.
TRUE or FALSE: The smaller the Weber fraction, the smaller the difference threshold. (hint: consider the formula for Weber’s fraction)
FALSE –> the BIGGER the Weber fraction, the smaller the difference threshold
What is the difference between bottom-up processing and top-down processing?
bottom-up: assembling individual pieces of info from environment and building perceptions based on this NEW info
top-down: using an EXISTING framework of knowledge to form a perception
What do the Gestalt principles describe? How do they relate to top-down processing?
describe how we distinguish OBJECT FROM BACKGROUND; top-down processing is used to group sensory info into distinct regions called FORMS
What are the 5 Gestalt principles used to group stimulus information?
- closure
- proximity
- continuation
- similarity
- figure and ground
What is the difference between a monocular depth cue, a binocular depth cue, and an oculomotor cue?
monocular cues: cues that work with one eye
binocular cues: cues that involve both eyes
oculomotor cues: cues that involve the brain sensing motor movement from muscles in our eyes
When objects are FAR AWAY (from us), which type of depth cue does the brain use?
a) monocular
b) oculomotor
a) monocular
When objects are CLOSER (to us), which type of depth cue does the brain use?
a) monocular
b) oculomotor
b) oculomotor