Sensation and Perception - five key senses

Question 1

components of the eye

Answer 1

from outer later of the eye to the inner layer of the eye:

1. cornea - light refraction (helps direct and focus light so you can see it clearly)
2. pupil - light regulation via iris actions (iris - the dark colour of your eye, determines how much light enters.) lots of light = pupil makes iris smaller to let less light in. dark/no light = pupil makes the iris bigger.
3. lens - light refraction and focusing light through accommodation (accommodation is when the lens changes shape to help focus on things that are close or far away.) when looking at something nearby = lens gets thicker. when looking at something far away = lens gets thinner.
4. retina - light absorption, image processing, and communication to the brain (retina absorbs light that comes in and turns it into signals. the retina has special cells that process light into images. these signals are sent to the brain so it can understand what you’re seeing).

Question 2

pathways

Answer 2

• the visual processing of the eye and brain.

Step 1: light enters the eye
Step 2: receptor (light detected by photoreceptor cells - clone and rod cells) in the retina convert light into electrical signals
step 3: bipolar cells (electrical signals from the photoreceptors are transmitted into bipolar cells which act as intermediates, processing the info further.)
step 4: ganglion cells (bipolar cells send the processed signals to the ganglion cells whose axons combine to form optic nerve.)
step 5: optic nerve at optic disk - optic nerve exits the eye and into the brain for processing).

Question 3

stimuli

Answer 3

• light (electromagnetic radiation)
• wavelength smaller than visible light = fall into UV spectrum (uv rays and gamma rays).
• wavelengths larger than visible light = fall into infrared spectrum (radio waves, microwaves, infrared).

Question 4

receptors

Answer 4

2 types:

1. rod cells
2. cone cells

Question 5

characteristics of visual stimuli

Answer 5

1. Amplitude - how bright it is (peak to troph)
2. wavelength - what the colour is (hue) (peak to peak)
3. purity - how saturated the colour is.

Question 6

rod cells

Answer 6

• high quantity
• role: help you see better at night and help peripheral vision.
• located in the peripheral region (sides of the eye)

Question 7

cone cells

Answer 7

• low quantity
• role is to help you see colour (red, blue, and green).
• are best during the day and provide sharpest vision because they are concentrated in a part of the retina called foreva

Question 8

fovea

Answer 8

• area in the retina that gives you clearest vision and ability to see fine details.