Sensory Anatomy Quiz - Practical 2

Sensation

Sensation

the process by which information about the environmental stimuli is received by a sensory receptor and then converted to action potentials that are sent to the brain

ex: thermoreceptor responding to a change in temp at skins surface and producing an action potential

Perception

involves the brain receiving and interpreting the action potentials such that we are consciously aware of sensation

ex: temp info is sent to the brain the interpret as hot or cold

Exteroceptor

sensitive to stimuli arising outside the body

Interoceptor

sensitive to stimuli arising inside the body

Mechanoreceptor

a sensory receptor that responds to mechanical stimuli such as touch, pressure, and vibration

stimulated by physical deformation of the receptor

smaller receptor area = more sensitive skin

Proprioceptor

a sensory receptor found in muscle, joint, and tendon tissue that detects changes in body position or movement

monitors joint position and stretch, joint angles, tendon tension, and muscle stretch to produce uncoordinated movement

Thermoreceptor

a sensory receptor that responds to changes in temperature

Photoreceptor

a sensory receptor that detects light or changes in light

provide visual information to the brain so it can understand how body parts are positioned

found only in the eyes

Chemoreceptor

a sensory receptor that responds to chemicals in solution

Nocireceptor

a sensory receptor that responds to stimuli that are harmful to the body

Receptor

a cell or nerve ending of a sensory neuron specialized to respond to particular types of stimuli

protein that binds specifically with other molecules like neurotransmitters, hormones, paracrines, and antigens

Integration Center

where the nervous system processes and interprets sensory input and makes decisions about what should be done at each moment

Effector Organ

muscle, gland, or organ capable of being activated by nerve endings

Intrinsic Reflex Arc

require no experience or learning to be carried out by the body

ex: spinal reflex arc

Spinal Reflex Arc

type of intrinsic arc

associated with very rapid movement of skeletal muscle tissue

integration system is spinal cord

ex: touching a hot stove

Pupil

open space at the center of the iris that allows light to enter the eye and strike the retina

has two muscles that control diameter and light entering the eye

Dilator Pupillae Muscle

muscle of the iris that causes the pupil to widen when it contracts

Sphincter Pupillae Muscle

muscle of the iris that causes the pupil to narrow when it contracts

Consensual Reflex

the stimulus is applied to only one side of the body, but the response or output is observed on both sides of the body

Lens

structure inside the eye that helps to focus light directly on the retina by bending light as it enters the eye allowing for clear vision

Pupil Accommodation

the size of the pupil changes according to distance of object requiring focus to adjust the amount of light entering the eye

Lens Accommodation

the lens can change shape to change the ability to refract or bend light to focus it on the retina

the more round (bulging) the lens = the stronger the refractory power

Refraction

the bending of a light ray when it meets a different surface at an oblique rather than right angle

Refractory Power

the amount of deflection or scatter of light that occurs as it passes the lens

determined by how scattered light rays are as they enter the eye

if an object is close = light is more scattered = higher refractory power = rounder lens

Convergence

ability to turn the eyes inward to look at a close object

requires the use of medial and lateral rectus eye muscles

Converge

the process of both eyes moving or pointing inward to focus on an object

Knee Jerk Reflex

occurs when the patellar tendon just below the patella is stretched when its tapped by a reflex hammer

assesses the l2-l4 spinal cord level

Jendrassik’s Maneuver

alters the patellar reflex by forcing the individual to focus their attention somewhere else in the body rather than thinking about the patellar reflex

Ankle Jerk Reflex

occurs when the achilles tendon on the back of the ankle is tapped

assesses the s1 nerve root

Antagonistic Muscle

muscle that reverses, or opposes the action of another muscle

the muscle that relaxes, pairs usually have opposing actions on a part of the body

when the muscle contracts, this lengthens

Palpate

examine by touch

Ciliospinal Reflex

response mediated by the sympathetic nervous system (fight or flight) in response to pain

Babinski Reflex

an abnormal plantar reflex that occurs when the big toe moves upwards and other toes fan out after the sole of the foot is stroked

normal in kids under 1

Plantar Flexion

toes bending or curling downward

Dorsiflexion

the big toe pointing or curling upward

Semicircular Canals

three fluid filled tubes in the inner ear that contribute to balance and equilibrium when moving by aiding visual fixation on moving objects

Nystagmus

a reflexive movement of the eyes caused by the stimulation of semicircular canals

Anterior Semicircular Canals

stimulated by forward and backward head movement

ex: doing a front or back flip

Posterior Semicircular Canals

stimulated by movement causing the head to tilt to the side

ex: doing a cartwheel

Lateral Semicircular Canal

stimulated by movement where the head spins or moves side to side

ex: spinning in a circle

Fast Phase Nystagmus

eyes moving fast during nystagmus

the direction of nystagmus is designated as that of this phase

Slow Phase Nystagmus

eyes moving slow during nystagmus

Angularly Accelerating

causes the eyes to move slowly in one direction (slow phase) as though to maintain fixation on a moving target, then rapidly move or twitch to opposite direction (fast phase)

Rotary Nystagmus

can be observed during movement when the fluid in the semicircular canal moves or flows stimulating receptors in the inner ear

Post Rotary Nystagmus

when the eyes continue to move reflexively after movement has stopped

fast and slow phase here is opposite to rotary

Spatial Orientation

ability to maintain the body’s position and posture in relation to our surroundings so we don’t bump into things

Inner Ear

receptors here respond to changes in head position during linear acceleration

Two Point Threshold

the smallest distance at which two points of contact can be felt

Sensory Adaptation

when a stimulus is applied for a long period of time without change, the rate of receptor discharge will slow and conscious awareness of the stimulus will decline or is lost until a change occurs

Conduction Deafness

results from damage to structures from the tympanic membrane to the auditory ossicles

prevents transmission of sound to the inner ear

Nerve Deafness

form of deafness that occurs when auditory nerve or brain is damaged such that action potentials relating to sound are not produced by auditory nerve or cannot be interpreted by the brain

No Hearing Loss Webber

no lateralization

Conduction Deafness Webber

lateralization to the poorer ear

Conduction Deafness Rinne

sound perceived longer by bone conduction

Nerve Deafness Webber

lateralization to the better ear

Nerve Deafness No Hearing Loss Rinne

sound perceived longer by air conduction

Near Point

the closest point at which an object can be placed from the face and still form a focused image within the eyes accommodation range

demonstrates the elasticity of the lens and its ability to accommodate when viewing an object up close

Lens Aging

lens becomes less flexible and accommodation becomes less effective

Presbyopia

loss of near focusing ability caused by lens not bulging enough when viewing up close objects

Optic Disc

area of the back of the eye on the retina where there are no photoreceptors for visual reception

blind spot

Visual Acuity

sharpness of vision, involving the ability to discern letters or numbers at a given distance according to a fixed standard

Snellen Test

uses a chart with letters of different sizes to see if letters can be seen clearly at different distances and sizes

V

a persons visual acuity

d/D

d is the distance at which a patient can read letters in a row and D is distance of a normal eye reading letters in the same row

Myopia

caused by a misshaped eyeball that cannot have light correctly focus on the retina

nearsightedness

Hyperopia

caused by shape of the eyeball with light not being focused directly on the retina

farsightedness

Young Helmholtz Theory of Color Vision

one type of photoreceptor in the eye allows for color vision, different cones respond to different colors (red, blue, and green)

Cone

photoreceptor in the eye allowing for color vision

Red Green Colorblindness

person lacking either red or green cones in the retina

X linked where xy is more likely to have it then xx

Ishihara Test

a test for colorblindness consisting of collections of different colored dots arranged in numbers on a plate