sensation/perception/attention Flashcards
what is a stimulus (in sensation)
event registered by our senses and gives about a response (physiological or psychological)
What are the properties of a stimuli?
- occurs via sensory organs
- may be distant or proximal (outside or inside our bodies)
What are the 5 sensory modalities?
- vision
- audition
- gustation
- olfaction
- somatosensation (touch, pressure, proprioception, balance)
What is transduction?
process by which the sense organs convert energy from environmental events into neural activity
What types off sensory coding are there?
- anatomical coding
- temporal coding
What are the features of anatomical coding?
- each sensory modality has its own sets of nerves
- distinction between stimuli of the same modality
What are the features of temporal coding?
rate of firing of axons (reflects how strong the stimuli is)
What is psychophysics?
systematic study of the relation between the physical characteristics of stimuli and the sensation they produce
What is psychophysics used to measure?
- absolute threshold: minimum level of a stimulus that can be detected
- different thresholds: minimal detectable difference between two stimuli
What is signal detection theory?
discriminating between a ‘signal’ and ‘noise’ (background stimuli and random neural activity)
What is perception?
our interpretation of what is represented by sensory input
What are the Gestalt principles?
laws by which visual system help to perceive the forms of objects and all visual input that we are receiving
Name the Gestalt principles
- the adjacency/proximity principle
- similarity principle
- good continuation
- the law of closure
- principle of common fate
What are the theory is perception of form? (how does the brain recognise stimuli so fast?)
models of pattern recognition:
- templates
- prototypes
- feature detection models
What are top-down influences on perception?
influences of higher brain functions in interpretation of stimuli that we see
What are features of top-down perception?
- size and shape consistency + depth perception
- the context in which we encounter something
- perceptual set (selectivity and bias i.e. previous experiences, expectations etc)
What is (selective) attention?
allocation of awareness to stimuli
What is shifting attention?
reallocation of attention
What does shifting attention compromise of?
- disengagement
- shifting
- focus
What is bottom up attention?
reflexively/automatically (i.e. in response to a stimulus appearing suddenly)
What is top down attention?
consciously directed (i.e. looking out of the corner of your eye as someone tell you where to look)
