the senses Flashcards
what is a sense?
one of the faculties by which the qualities of the external environment are appreciated
what information do the senses provide?
information about the changes in the external and internal environments
a sense organ is a collection of what?
specialised receptor cells
a sense organ is a system that is capable of what?
responding to a particular stimulus from outside or inside the body
what are the 6 things the sense organs can detect?
light
heat
pain
touch
smell
taste
What are the 4 things needed for a sensation to occur?
- a stimulus
- a receptor
- conduction of the impulse to a neural pathway
- a region of a brain to translate impulse into sensation
What does the stimulus do when a sensation occurs?
initiates a response by the nervous system
What does a receptor do when a sensation occurs?
pick up the stimulus and convert it to a nerve impulse
what does a neural pathway do when a sensation occurs?
conducts the impulse from the receptor to the brain
What does the brain do when a sensation occurs?
translates the impulse into a sensation
what does the general somatosensory area in the brain do?
it interprets a bodily sensation
which are the three receptors that the parietal lobe in the somatosensory area gets sensations from?
cutaneous
muscular
visceral
the parietal lobe in the somatosensory area perceives what 6 things?
- pain
- temperature
- touch
- pressure
- awareness of muscular movement
- position of joints
the parietal lobe in the somatosensory area can tell you the exact ______ of the _____ where sensations _________.
point
body
originate
where does the somatosensory association area get its input from? (3)
the thalamus, other lower portions of the brain and the general sensory area
What is the role of the somatosensory association area?
to integrate and interpret somatic sensations
The somatosensory association area allows you to determine the ________ shape and __________ of an object without looking at it.
exact
texture
the somatosensory association area allows you to determine the ___________ of one ________ to another as they are felt.
orientation
object
the somatosensory association area stores ___________ of past _________ __________ allowing you to __________ past with present sensory experiences.
memories
sensory experiences
compare
where is the primary visual area in the brain?
the occipital lobe
what does the primary visual area do?
receives input from the eyes and interprets these as visual impressions
where is the visual association area?
in the occipital lobe
what is the role of the visual association area?
it relates past to present visual experiences and is needed to recognise and evaluate what is seen
where in the brain is the primary auditory area located?
in the temporal lobe
what is the role of the primary auditory area?
to receive sound and interpret information via impulses from the inner ear
what basic characteristics of sound does the primary auditory area interpret? (3)
sound, pitch and rhythm
Where is the auditory association area located?
in the temporal lobe
what does the auditory association area determine?
if sound is speech, music or noise
where is the primary gustatory area located?
in the parietal lobe
what does the primary gustatory area do?
receives impulses via taste buds and perceives these as taste
Where is the primary olfactory area located?
in the temporal lobe on the medial aspect
what is the role of the primary olfactory area?
to receive impulses from the nose and interpret these sensations as related to smell
Mechanoreceptors are sensory receptors that sense what? (6)
touch
pressure
vibration
proprioception
hearing equilibrium
blood pressure
nociceptors are sensory precepts that detect what? (1)
pain - usually because of physical or chemical damage to tissues
photoreceptors are sensory receptors that detect what? (1)
light on the retina of the eye
Chemoreceptors are sensory receptors that detect what? (3)
taste
smell
chemicals in body fluids (eg oxygen, Co2, glucose)
Where are thermoreceptors (a type of sensory receptor) located?
in skin and elsewhere
What do thermoreceptors ( a type of sensory receptor) respond to?
changes in temperature
What is smell referred to as?
olfaction
what sense organ is involved in smell?
nose
Where in the nose does the sense of smell originate in?
the nasal cavity
as well as smell, the nasal cavity is a passageway for what?
respiration
where do the nerve fibres of the nose originate?
in the upper part of the mucus membrane
The specialised ______________ ___________nerves in the nose pick up information of an incoming odour. They pass it to the ____________ _____ which continues as the _________ ______ to the ___________ lobe of the ___________.
chemoreceptor
olfactory
olfactory bulb
olfactory tract
temporal
cerebrum
what is the scientific name for taste?
gustation
what is the sense organ involved in taste?
the tongue/taste buds
where in the tongue do the the taste buds lie? (4)
the papillae, soft palate, pharynx and epiglottis
Taste buds are ______ in structure and form ________ of _____ _______ and ______ __________ of the ________________, _____ and ______ _______ nerves.
round
bundles
cell bodies
nerve endings
Some taste buds have taste ______ which are stimulated by food and drink. The ______ lead to _______ which allow the ________ in. The dissolved ______________ in the saliva stimulate ________________. These generate and send messages (____________ __________) via the __________ nerves to the _________ area in the ____________ lobe for ____________.
hairs
hairs
pores
saliva
chemicals
chemoreceptors
chemical impulses
cranial
taste
parietal
interpretation
although taste varies from person to person, what are the four general areas of taste?
sweet, bitter, sour and salt
which part of the tongue is stimulated by sweet and salty tastes?
the tip of the tongue
which part of the tongue is stimulated by sour tastes?
the sides
which part of the tongue is stimulated by bitter tastes?
the back
why can’t we taste well when our mouth is dry?
because we can only taste when substances are in solution
how does taste act as protection?
because when foul-tasting food enters the mouth and is eaten, reflex gagging or vomiting may be induced
what are the sense organs in hearing?
ears
ears are associated with which two sensory functions?
hearing and balance
what sensory receptors are involved in hearing?
mechanoreceptors
when we hear a noise, where are sound waves picked up and transferred to? via what? for what?
picked up in the ear
transmitted to cerebrum via 8th cranial nerve for interpretation
auditory messages are sent via which nerve to the cerebrum and cerebellum? to do what?
the auditory nerve to detect changes in the position of the head
once the auditory signals are interpreted, what happens?
the skeletal muscles are instructed to maintain balance and posture
what sense organs are involved in sight?
the eyes
what kind of receptors does vision use? where are they located?
photoreceptors located in the eye
where does light enter the eye through? which then strikes what?
the pupil
the retina
what are the two light sensitive structures in the retina?
rods and cones
what do rods and cones in the retina do? where is it sent?
they convert incoming light into nerve impulses which are then sent to the optic nerve for interpretation
some sensations are felt more __________ than others.
strongly
What is an example of selective awareness in senses?
waking up to a sick screaming child but not a train
The effect of a current sensation may be _______________ when the brain compares it with a _________ ___________.
exaggerated
previous sensation
What is an after-image? give an example
when the stimulus stops but we remain aware of the sensation eg when you are able to see a light image after closing eyes
What is adaption in sensory characteristics? give an example
when a stimulus is still present but we become unaware of it eg becoming nose blind
why does adaption happen?
due to a decrease in the strength of a sensation due to a prolonged stimulus, partly caused by a decrease in responsiveness
