Lecture 2 (Methods) Flashcards
What are the main scientific methods and approaches in this subject?
> Ecological
Psychophysical
Neurophysiological
Modeling/Reverse Engineering
Ecological method
Studying organisms in their natural environment
STRENGTHS
> Real-world applicability
> Behavior in context
WEAKNESSES
> Controlling variables
> not generalizable
> precision
Psychophysical method
Relationship between physical stimuli and sensory perception
STRENGTHS
> Precise sensory thresholds
> quantifying perception
WEAKNESS
> Perception is subjective
> individual differences
Neurophysiological method
Brain’s electrical activity & neural processes
STRENGTHS
> Direct insight into connectivity & function
WEAKNESSES
> Complexity of interpreting data (linking neural activity to any one specific process)
> Invasiveness of techniques
Reverse engineering/modeling
Creating a replica or model of a neural network/the brain
STRENGTHS
> Predict system functions
> uncover underlying mechanisms
WEAKNESSES
> oversimplification
> incompleteness
> accurate models (complexity)
Basic Measurements for thresholds
> Two-point threshold
Just noticeable difference (JND)
absolute threshold
Two-point threshold
The minimum difference that two stimuli are perceived as separate
DISTANCE
Just Noticeeable Difference (JND)
The smallest difference in INTENSITY between two stimuli that can be detected
Absolute threshold
Lowest possible stimulus before it is not perceived at all.
Weber’s Law
JND is constant proportion
Fechner’s Law
The perceived intensity of a stimulus is logarithmic
What are the three early psychophysical laws
> Weber’s Law
Fechner’s Law
Stephens’ power Law
How are Weber’s Law and Fechner’s Law conceptually related
They both apply to the same concept, using diff scales of measurement
What is signal detection theory
Ability to detect signal amidst uncertainty (incorporates personal bias)
> explains why some people may detect the same stimulus differently depending on individual factors
What are the four response types in SDT
Hit, miss, false alarm, correct rejection
Stephen’s power law
Relationship between intensity of the stimulus and perceived magnitude of the stimulus
What are the 4 psychophusical methods
> Method of constant stimuli
Method of limits
Method of adjustment
Magnitude estimation and cross-modality matching
Method of constant stimuli
Different intensities in random order (threshold of 50% detection; JND)
STRENGTHS
> Precise
> reliable for varying levels of intensity
WEAKNESSES
> Time consuming
> Large number of stimuli and trials
Method of limits
Stimuli in systemic order, fixed steps
STRENGTHS
> Faster, fewer traisl
> Simpler
WEAKNESSES
> Response bias
> Expectation
Method of adjustment
Adjusting until it is just barely detectable, continuous
STRENGTHS
> Quick & easy
> Variety of stimuli
WEAKNESSES
> Bias (participant controls)
> Less accurate measurements
magnitude estimation and cross-modality matching
Numerical values to the perceived intensity
STRENGTHS
> Relation of senses (modality)
> Comparisons
> wide range of stimuli
WEAKNESSES
>subjective
>not consistent
> personal bias
Neuroscience revirew
mark as one
