CHP. 14: SENSATION AND PERCEPTION: TASTE AND VISION Flashcards
What are the five senses?
Vision, taste, touch, smell and hearing
What are the sense organs for all five senses?
Vision = Eyes Taste = Tongue Touch = Skin Smell = Nose Hearing = Ears
What are the sense receptors for sight and where are they located?
Rods and cones
Located in the retina
What are the sense receptors for taste and where are they located?
Taste receptors,
Located in the taste buds
What are the sense receptors for touch and where are they located?
Receptors for pressure, heat and cold,
Located in the skin
What are the sense receptors for smell and where are they located?
Olfactory cilia,
Located in the nasal epithelium
What are the sense receptors for hearing and where are they located?
Hair cells,
Located in the cochlea
What is the stimulus energy for all five senses?
Vision = Light Taste = Chemicals Touch = Kinetic Smell = Chemical Hearing = Sound
Define the absolute threshold
The minimum amount of stimulus energy needed for an observer to perceive a stimulus, in ideal conditions, 50% of the time
What are the six stages of sensation and perception?
SENSATION
Reception
Transduction
Transmission
PERCEPTION
Selection
Organisation
Interpretation
Define the Sensation stages of the Six stages of sensation and perception
RECEPTION: the stimulus energy is collected by the sense organ
TRANSDUCTION: the stimulus energy is converted by the receptor cells into electrochemical nerve impulses
TRANSMISSION: the receptor cells send the nerve impulses to the primary sensory cortex where specialised receptor cells respond
Define the Perception stages of the six stages of sensation and perception
SELECTION: the important stimuli are selected to be paid attention to out of the millions of stimuli we receive
ORGANISATION: when the information reaches the brain, it is recognised so we can make sense of it
INTERPRETATION: past experiences, motives, values and context are involved in the process where the stimuli is given meaning
Define the sensation stage of the six stages of sensation and perception in vision
SENSATION
Reception: light enters the eye through the cornea and passes through the pupil where the lens focuses the light on the retina which contains the photoreceptors
Transduction: light energy is converted by rods and cones into electrochemical nerve impulses
TRANSMISSION: the nerve impulses are sent along the optic nerve to the primary visual cortex where specialised receptor cells respond
Define the perception stage of the six stages of sensation and perception in vision
PERCEPTION
Selection: the image is broken up by specialised cells called feature detectors
Organisation: the visual cortex reorganises information so that we can make sense of it
Interpretation: the process whereby the visual stimulus/object is given meaning by comparing incoming information with stored information
Wavelengths between _______ and _______ form the visible spectrum
360 to 760 nanometers
Define the role of the eye in visual perception
Light enters the eye through the cornea. It then passes through the pupil to the lens, where it is focused onto the retina which contains photoreceptors (light sensitive cells)
Define rod cell photoreceptors
There are 125 000 000 in the eye
They are responsible for vision in low light and peripheral vision
They have low visual acuity (can’t register detail) and can only register in black and white
Define cone cell photoreceptors
There are 6 500 000 in the eye
They are responsible for vision of detail and colour vision (and black and white vision in daylight)
They require high levels of light to be able to respond
What is the benefit to humans and animals being able to taste?
In order to determine which foods are safe to eat and which may be bitter and dangerous
How many taste buds are located on the tongue and throat?
10 000
How many taste receptor cells are contained in each of the taste buds?
50-150
How long do taste cells live?
About 10 days
What are the five primary tastes?
Sweet, sour, bitter, salty and umami (savoury)
Which cortex is responsible for taste?
The gustatory cortex
Do certain taste buds detect only one primary taste?
No. All taste buds can receive all tastes but each is slightly more sensitive to one of the five primary tastes; thus certain areas of the tongue respond slightly more strongly to one taste sensation
Define the sensation stage of the six stages of sensation and perception in taste
SENSATION
Reception: chemicals are dissolved in saliva during chewing
Transduction: chemical energy is converted by receptor cells on the taste buds into nerve impulses
Transmission: the nerve impulses travel to the primary gustatory cortex
Define the perception stage of the six stages of sensation and perception in taste
For taste alone, perception is a very simple process- the brain simply recognises the sensation of a mixture of the five primary tastes, but combined with the smell of the food, the colour and texture.
Define flavour
Taste Perception involves the senses of vision, taste, smell and touch leading to interpretation of flavour
