senses of the body

hearing, vision, taste, smell, touch, balance, thermoception, proprioception and pain.

senses of the body

hearing, vision, taste, smell, touch, balance, thermoception, proprioception and pain.

general senses vs special senses.

general are found all over the body and do not have their own specialised organs. specials are found only in the head and do not have their own specialised organs.

general senses vs special senses.

general are found all over the body and do not have their own specialised organs. specials are found only in the head and do not have their own specialised organs.

4 special senses.

hearing & balance, vision, taste and smell.

4 special senses.

hearing & balance, vision, taste and smell.

transduction definition.

sense organs have specialised sensory receptor cells that translate stimuli into electrical signals. this process is called transduction.

transduction definition.

sense organs have specialised sensory receptor cells that translate stimuli into electrical signals. this process is called transduction.

sensation vs perception.

a sensation is the raw input from the peripheral nervous system that arrives the central nervous system. a perception is the brain interpretation of a sensation.

sensation vs perception.

a sensation is the raw input from the peripheral nervous system that arrives the central nervous system. a perception is the brain interpretation of a sensation.

cornea & lens.

the cornea transmits and focuses light into the eye from different angles. the lens focuses light rays onto the retina. it is avascular and held in place by ligaments.

cornea & lens.

the cornea transmits and focuses light into the eye from different angles. the lens focuses light rays onto the retina. it is avascular and held in place by ligaments.

pupil & iris

iris: coloured part of the eye that helps regulate the amount of light that enters. pupil: dark aperture in the iris that determines how much light is let into the eye.

pupil & iris

iris: coloured part of the eye that helps regulate the amount of light that enters. pupil: dark aperture in the iris that determines how much light is let into the eye.

retina, macular & optic nerve.

retina: nerve layer that lines the back of the eye, sense light, and creates electrical impulses that travel through the optic nerve to the brain (peripheral vision). Macular: small central area in the retina that contains special light-sensitive cells and allows us to see fine details clearly (central vision). optic nerve: connects the eye to the brain and carries the electrical impulses formed by the retina to the visual cortex of the brain.

retina, macular & optic nerve.

retina: nerve layer that lines the back of the eye, sense light, and creates electrical impulses that travel through the optic nerve to the brain (peripheral vision). Macular: small central area in the retina that contains special light-sensitive cells and allows us to see fine details clearly (central vision). optic nerve: connects the eye to the brain and carries the electrical impulses formed by the retina to the visual cortex of the brain.

photoreceptors. rods and cones

rods: shades of grey in dim light. 120 million rod cells. allows vision for shapes & movements. distributed along the periphery. cones: specialised for clarity and colour. 6 million. found inside the macula.

photoreceptors. rods and cones

rods: shades of grey in dim light. 120 million rod cells. allows vision for shapes & movements. distributed along the periphery. cones: specialised for clarity and colour. 6 million. found inside the macula.

refraction of light.

bending of light as it passes from one substance to another (air) into a 2nd substance with a different density (cornea/lens).

refraction of light.

bending of light as it passes from one substance to another (air) into a 2nd substance with a different density (cornea/lens).

image focus.

image focused on retina is inverted & reversed from left to right brain corrects information. 75% of refraction is done by the cornea, 25% is done by the lens.

image focus.

image focused on retina is inverted & reversed from left to right brain corrects information. 75% of refraction is done by the cornea, 25% is done by the lens.

vision distance.

if distant vision is required, the ligaments are pulled tight and the lens flattens. if close vision is required, the ligaments are loosened and the lens bulges. as we age our lens becomes less elastic, causing presbyopia.

vision distance.

if distant vision is required, the ligaments are pulled tight and the lens flattens. if close vision is required, the ligaments are loosened and the lens bulges. as we age our lens becomes less elastic, causing presbyopia.