Sensory Reception Flashcards
Compare sensory reception and sensation. Provide an example of each.
Sensory Reception - The senses transmit sensory information, in the form of electrochemical impulses, to the brain.
For Example: the nerve endings and cells that detect sensory information - then initiate neural impulse.
Sensation - occurs when the neural impulses arrive at the cerebral cortex.
For Example: the detect the warmth of a beam of sunlight.
Each type of sensory receptors functions by initiating neural impulses. How is the brain able to convert sensory information into perception?
- Neural Impulses that begin to the optic nerves are sent to the visual areas of the cerebral cortex, and we see objects.
- Neural Impulses that begin in the auditory nerve of the ear are sent to the area of the brain that perceives sound, and we hear sounds.
- Each person’s unique perception results from how the cerebral cortex interprets the meaning of the sensory information
Describe an example of sensory adaptation, and explain why it occurs.
Sensory Adaptation - A massive amounts of sensory information, coming from many neural pathways.
- The brain can filter out redundant insignificantly information.
For Example: no longer notices the ticking clock or feel the clothes on the skin.
- When the senses detect a significant change in external or internal conditions, the body readjusts.
What happens during integration that causes people to perceive optical illusion?
The sensory information does not get reintegrated precisely, and what we sense is not necessarily what we perceive.
The effect can be demonstrated with optical illusions which scientists use to try to understand how the brain perceives sensory information.
Identify five majors senses and their corresponding sensory receptors.
Photoreceptors - lights energy stimulates; called rods and cones that absorbs light and allow us to sense different levels of light and shades of colour.
Chemoreceptors - are stimulated certain chemicals; tongue contains taste buds that detect various particles in the food we ear.
- The nose has olfactory cells that detect occurs in the air; detect changes in the internal environment
Mechanoreceptors - respond to mechanical forces from some form of person
- Hair cells in the inner ear (Hearing sensors)
- Other hair cells in the inner ear (sensors for balance)
Proprioceptors - in and near the muscles also provide information about body position, as well as movement.
Thermoreceptors - skin detect heat and cold
List three types of internal sensory receptors and their functions
- Thermoreceptors detect changes in temperature.
- Mechanoreceptors detect mechanical forces.
- Photoreceptors detect light during vision.
Identify the key structures of the EYE and their functions
How do the eyes adjusts to changing light intensities?
Name this process
Light adaptation in the eye. In brights light, the iris constricts, which shrinks the pupil to let in less lift. In dim light, the iris dilates, which widens the pupil and lets in more light.
Adaptation the iris adjusts the size of the pupil based on the light conditions process
How does glaucoma occur, and how can it cause blindness?
Optic nerve damage from fluid buildup in the eye. Left untreated, this eye pressure can permanently affect vision. Glaucoma is the second leading cause of blindness in the world.
Describe the functions of the cornea and lens of the eye.
- The cornea directs light rays into the eye and helps focus them on the light-sensitive retina at the back of the eye, providing sharp, clear vision.
- The lens is located behind the iris and is normally clear. Light passes through the pupil to the lens.
What causes astigmatism, myopia, and hyperopia?
Cause…..
Astigmatism - often hereditary, which means it’s passed down from your parents. It can also be the result of eyelids putting pressure on the cornea
Myopia/Nearsightedness - the shape of your eye causes light rays to bend (refract) incorrectly, focusing images in front of your. retina instead of on your retina.
Farsightedness/Hyperopia - a cornea (the clear layer at the front of the eye) that isn’t curved enough or by an eyeball that’s too short.
Compare adaptation with accommodation. Give an example of each.
Accommodation
- If an object is nearby, the ciliary muscles contract and the suspensory ligaments relax, causing the lens to become more rounded.
- A non-digital camera focusses by changing the distance between the lens and the film.
- The ability of the lens to change shape in order to focus images clearly on the retina is a reflex.
For Example: an extended period of time. the ongoing contraction of your ciliary muscle will likely cause muscle fatigue - experience as eyestrain.
Compare the locations and functions of the two photoreceptors found in the eye.
The rods also detect motion and are responsible for peripheral vision.
- the rods are spread throughout the retina, but are more concentrated in the outside edges.
The cones - are the colour detecting sensors of the eye.
- They are packed most densely at the fovea centralists at the back and centre of the retina.
- require relatively intense light to stimulate them
- the structure of the eye must focus light onto the fovea centralists in order to produce a sharp image.
What is the direct cause of red-green colour blindness?
Colour Blindness is an inherited conditions that occurs more frequently in males then in females
- Color Blindness is actually colour deficiency, because it is caused by a lack or deficiency in particular cones, usually red and green cones.
How does visual information get from retina to the brain?
List the main steps in this process.
- The retina converts the image formed by the light rays into nerve impulses.
- The optic nerve, composed of the axons of the retina’s ganglion cells
- transmits these impulses from the eye to the first visual relay in the brain.
List, in order, the structures of the ear that a sound wave encounters, starting with the outer ear.
- Sound waves enter the outer ear and travel through a narrow passageway called the ear canal, which leads to the eardrum.
- The eardrum vibrates from the incoming sound waves and sends these vibrations to three tiny bones in the middle ear. These bones are called the malleus, incus, and stapes.
- The bones in the middle ear amplify, or increase, the sound vibrations and send them to the cochlea, a snail-shaped structure filled with fluid, in the inner ear. An elastic partition runs from the beginning to the end of the cochlea, splitting it into an upper and lower part. This partition is called the basilar membrane because it serves as the base, or ground floor, on which key hearing structures sit
- Once the vibrations cause the fluid inside the cochlea to ripple, a traveling wave forms along the basilar membrane. Hair cells—sensory cells sitting on top of the basilar membrane—ride the wave. Hair cells near the wide end of the snail-shaped cochlea detect higher-pitched sounds, such as an infant crying. Those closer to the center detect lower-pitched sounds, such as a large dog barking.
- As the hair cells move up and down, microscopic hair-like projections (known as stereocilia) that perch on top of the hair cells bump against an overlying structure and bend. Bending causes pore-like channels, which are at the tips of the stereocilia, to open up. When that happens, chemicals rush into the cells, creating an electrical signal.
- The auditory nerve carries this electrical signal to the brain, which turns it into a sound that we recognize and understand.
