Chapter 5 - Sensation Flashcards
Sensation
-process through which senses detect visual, auditory, and other sensory stimuli and transmit them to brain
Perception
-process by which sensory info is actively organized and interpreted by brain (fills in blanks)
Sensory transduction
-converting info in environment into natural impulses
Absolute threshold
- difference b/w not being able to perceive a stimulus and being able to just barely perceive it
- minimum amount of sensory stimulation that can be detected 50% of the time
Difference threshold
-smallest increase or decrease in a stimulus that is required to notice a difference (50% of the time)
Inequality thresholds
- variation across senses
- weber fractions for various sensory modules
Bottom up processing
- individual components of stimulus detected by sensory receptors
- bits of info transmitted to areas of the brain to be combined and assembled into unified whole
Top-down processing
-past experience and knowledge influence our perceptions
Perceptual set
- where individuals’ expectations affect their perception
Sensory adaptation “not sensing”
- become less sensitive to unchanging sensory stimulus over time
- automatic
- shifts attention
Chemical sense
-rely on chemical molecules, not a form of energy
Anatomy of smell
- olfactory epithelium
- olfactory receptor neurons
- olfactory bulb
Smell/olfaction
- receptors line upper nasal cavity (40 mill)
- resemble neurotransmitter binding site (odour molecules lock to them)
- send info to olfactory area in brain (linked to amygdala, hippocampus)
Taste: sensation
- chemical receptors = taste buds (9000 in groups called papillae)
- routed through thalamus
Taste flavour gustation
-influenced by appearance, texture, previous experience
