Final Flashcards
Somatososensory Sense include
Cutaneous Sensation, Proprioception, Kinesyhesis
Cutaneous Sensation is
Any feeling originating in sensory nerve endings of the skin, including pressure, warmth, cold, and pain.
What is Proprioception
Ability to sense position of the body and limbs
Kinesthesis
Ability to sense, movement of body and limbs
Cutaneous System
Skin: Heaviest organ in the body
Our skin
Protects the organism by keeping damaging agents from penetrating the body
The first outer layer of the skin, which is made up of dead skin cells
Epidermis
This is below the upper dermis and contains mechanoreceptors that respond to stimuli such as pressure stretching, and vibration.
Dermis
Mechanoreceptors in epidermis
Two types located close to surface of the skin
________ receptor, fires continuously, while stimulus is present responsible for sensing fine details.
Merkel
______ corpuscle fires only when is stimulus is for supplied, and when it is removed. Responsible for controlling hand grip.
Meissner
What two types of receptors are located in the dermis? (deeper in the skin)
Ruffini cylinder and Pacinian corpuscle
_____ Fires continuously to simulation. Associated with perceiving stretching of the skin
Ruffini Cylinder SA2 fiber
_______ fires only when is stimulus is first applied and when it is removed. Associated with sensing rapid vibrations in fine texture.
Pacinian corpuscle RA2 or PC fiber
_____ fibers traveling bundles, (peripheral nerves) to the spinal cord
Nerve
Pathways from skin to __
Cortex
What are the three spinal cord pathways
Medial lemniscal, Spinothalamic, Thalamus
Medial lemniscal pathway consists of
Large fibers that carry proprioceptive and touch information
Spinothalamic pathway consist of
Smaller fibers that carry temperature in pain information
Both the Medial lemniscal and spinothalamic pathways
Cross over to the opposite side of the body and synapse in the thalamus
Signals travel from the thalamus to the
Somatosesnsory receiving area (S1) and the second receiving area (S2) in the parietal lobe.
_____ in neural functioning leads to multiple homuniculi and changes in how cortical cells are allocated to body parts
Plasticity
Perceiving details is through
Measuring tactile acuity
What are three ways of measuring tactile acuity
Two point threshold, grating acuity, raised pattern identification
Braille
Raised pattern identification: using such patterns to determine the smallest size that can be identified.
The braille alphabet consist of raised dots and a 2 x 3 matrix. The large blue dots indicate the location of the rays that, for each letter blind people read these dots by scanning them with their…..
Fingertips
Both two point thresholds and grating acuity studies show
There is a high density of Merkel receptors in the fingertips.
Merkel receptors are densely packed on the fingertips similar to cones in the fovea.
The function of Chemical senses….
The only sense where stimuli go into the body.
What are the gatekeepers of the body
- Identify things that should be consumed for survival
- Detect things that would be harmful and should be rejected
- Cause good and bad affective responses.
What are the five basic taste qualities and what are their functions
Salty: presence of sodium
Sour: presence of acid
Sweet: automatic acceptance response (energy)
Bitter: automatic rejection response (poisons)
Umami: described as meaty, brothy, savory, and associated with MSG
What are some connections between taste quality and a Substance Effect
- sweetness is usually associated with substances that have nutritive value.
- better is usually associated with substances that are potentially harmful.
- Salty taste indicates the presence of sodium
- however, there is not a perfect connection between taste and function of substances.
Shaped like cones in located over entire surface
Filiform
Shaped like mushrooms, and found on sides and tip
Fungiform
Series of folds on back and sides
Foliate
Shapes like flat mounds in a trench located at back
Circumvilliate
The receptor sheet for taste contains papillae
Tongue
The structures that give the tongue it’s rough appearance. There are four kinds, each with a different shape.
Papillae
Contained on the papillae. There are about 10,000 ______
Taste buds
Sounds that make up a taste bud. There are a number of cells for each bud, and the tip of each 16 out into a taste poor. One or more nerve fibers are associated with each cell.
Taste cell
Sites located on the tips of the T cells. They are different types of sites for different chemicals. Chemicals containing the sides cause transduction by affecting ion flow across the membrane of the taste cell.
Receptor sites
Taste buds are located in _______ except for filiform
Papillae
Each Tastebud has ____ taste cells with tips that extend into the taste pore
50-100
Transduction occurs when chemicals contact the
Receptor cites on the tips
What are the signals that travel along a set of pathways?
-Chorda tympani nerve from front and sides of tongue
- Glossopharyngeal nerve from back of tongue
- Vagus nerve from mouth and throat
- Superficial petronasal nerve from soft pallet
These pathways make connections in the nucleus of the solitary track in the
Spinal cord
After hitting the spinal cord, they travel to the thalamus followed by
Followed by areas in the frontal lobe, insula, frontal opervulum cortex, orbital frontal cortex
Experiment by Erikson
Population coding
Different taste stimuli were presented to rats, and recordings were made from the chorda tympani.
Across-fiber, pattern show the two substances, ammonium chloride and potassium chloride, which are perceived similar by humans, have similar population coating, but different from sodium chloride, which is perceived as different .
Experiment by Mueller et al.
-Genetic cloning was used to determine if mice could be created that possess a human receptor that responds to PTC.
-Normally mice don’t have this receptor respond to the substance
-The experiment was successful, but not all data showed the same results.
Applying _____ to the tongue blocks flow of sodium to taste receptors
Amiloride
Tasters, nontasters, and supertasters…
- Tasters have more taste buds than non-tasters.
- tasters have specialized receptors for these compounds.
- Super taster’s appear more sensitive to bitter substances than tasters.
Animals are _______ meaning they have a keen sense of smell that is necessary for survival
Animals are macrosmatic
Humans are ______ a less keen sense of smell that is not crucial to survival
Microsmatic
Humans can discriminate more than _______ different odors
One trillion
- find it difficult to identify odors
- only successful half of the time
Why is it difficult to map perceptual experience onto physical attributes of odorants
- there is no specific language for odor quality
- Some molecules that have similar structure, smell different and some that have different structure smell the same.
_______ located at the top of the nasal cavity
Olfactory mucosa
