Chapter 12, 13, 14
slowly
____ adapting receptors respond to stimuli with constant action potentials that don't diminish over time
anterolateral system
____ fibers transmit pain, temp, and nondiscrimiative touch stimuli in the anterolateral spinal cord
posterior columns/medial leminscal system
____ includes axons of neurons that transmit tactical info about discriminative touch and axons that convey info regarding proprioception or joint position
sensory
____ neurons are classified by two factors that determine the speed with which their peripheral axons conduct action potentials -the diameter of the axon and the thickness of its myelin sheath
sympathetic NS
____ tone dominates in blood vessels, which keeps them partially constricted
sensory stimuli sensory stimuli
_____ are those effects that cause the senses to respond. Multiple ____ from different regions of the brain can be pulled together into a single mental picture
tactile senses non discriminative touch crude touch
_____ pertain to fine or discrimination touch, include vibration, two-point discrimination, and light touch while ______ or _____ touch lacks the fine spatial resolution of the tactile senses
parasympathetic NS
_____ tone dominates in the heart, which keeps the heart rate at an average of 72 beats per minute
mechanoreceptors
are encapsulated either interoceptors or exteroceptors found in the musculoskeletal system, skin, and in many other organs they depolarize in response to anything that mechanically deforms the tissue, including the eternal stimuli such as light touch and vibration and internal stimuli such as stretch and pressure
thermoreceptors
are exteroceptors, most of which are slowly adapting receptors depolarize in response to temp changes -separate receptors detect hot and cold
photoreceptors
are special sensory exteroceptors found only in the eye depolorize in response to light
receptive fields
are the areas served by a particular neuron. The more branches a neuron possesses the larger the neurons ____
exteroceptors
are typically close to the surface of the body. They detect stimuli originating outside the body, including an objects texture, temp, and color; chemical odors in the air; and the level of light
nociceptors
are usually slowly adapting exteroceptors depolorize in response to these stimuli called nociceptors
reticular formation
autonomic centers are regions found in the ____ formation that the hypolamus is in contact with, which contains neurons that control the activity of preganglionic sympahtetic and parasympathetic neurons
forearm
body regions that are not as involved in sensing the environment have fewer neurons with larger receptive fields example of a body region with a large receptive field is the skin of the ____
fingertips
body regions whose primary function is sensing the environment contain many neurons with smaller receptive fields an ex of a body region with a small receptive field is the skin of the ____
dual innervation
both divisions innervate many of the same organs where their actions antagonize one another, a condition called ____
chemorecptors
can be either interoceptors or exteroceptors that are capable of binding to specific chemicals that, once bound, generate a receptor potential as sodium ion channels open depolorize in response to certain chemicals in body fluids or in the air
dermatome map
dermatomes can be combined to assemble a ____ that represents all (except the first cervical spinal nerve) of the sensory pathways to different parts of the body
merkel cell fibers
detect discriminative touch stimuli such as form and texture
sympathetic parasympathetic
dual innervation allows the ____ division to become dominant and trigger effects that maintain homeostasis during exercise of emergency periods the ____ division, on the other hand, regulates the same organs, preserving homeostasis between period of increased physical activity
hypothalmus
homeostasis is controlled centrally by the ____, brainstem, and reticular formation, and the actions carried out by the two divisions of the ANS
two-point discrimination threshold
is a method for measuring the relative size of receptive fields
referred pain
is a phenomenon whereby pain that originates in an organ is perceived as cutaneous pain the nerves that carry the pain signals from the heart serve these particular dermatomes
fastest
large diameter axons with thick myelin sheaths conduct the ___ impulses. such as axons that convey propriocpetive info to the CNS -its citric for this info to travel quickly because the CNS needs it to make adjustments during movement to maintain posture and balance
interoceptors
lie with the boys interior, where they detect stimuli originating inside the body, including BP, the stretch if an organ such as a skeletal muscle or the urinary bladder, and the concentration of certain chemicals in body fluids and body temp
ANS
maintenance of homeostasis is one of the bodys most essential functions, in which the ____ plays a critical role
adaptation
rapidly adapting receptors respond rapidly with high intensity to stimuli but stop sending signals after a certain time period, called ____. These receptors detect the initiation of stimulus but ignore ongoing stimuli
autonmomic tone
refers to the fact that neither division is ever completely shit down. The constant amount of activity from each division can be divided into the sympathetic and parasympathetic tone
special general
sensations can be grouped into 2 senses
encapsulated free
sensory receptors exist in many forms; some called ____ nerve endings are surrounded by specialized supportive cells while others, called ___ nerve endings, lack supportive cells
dermatomes
skin can be divided into different segments called ____ based on the spinal nerve that supplies the region with somatic sensation
slowest
small diameter axons with little myelin transmit action potentials the ____ pain and temp stimuli are conveyed to the CNS by such axons
CNS
stimuli are first detected by sensory neurons that transmit impulses to the _____. From that point, the stimulus is transmitted by sensory neurons to the CNS where the stimulus is integrated and interpreted by CNS neurons
spinothalamic
thalamic nuclei relay touch info from the _____ tracts and posterior columns primarily to S1 for conscious perception
sympathetic parasympathetic
the ____ and ____ divisions work together to keep many of the body functions within their normal homeostatic ranges
thalamus somatotopy
the ____ relays most incoming info to the primary somatosensory cortex, or SI, in the post central gyrus, where each part of the body is represented by a specific region of SI, a type of organization called _____
sensory transduction
the conversion of a sensory stimuli to an electrical signal
nociception
the perception of pain stimuli is called _____
proprioceptors
***6 classes of mechanoreceptors*** are found in the musculoskeletal system detect the ability to sense its position in space and to monitor ongoing movement -critical for the integration of sensory and motor function
hair follicle receptors
***6 classes of mechanoreceptors*** are free nerve endings surrounding the base of hair follicles found in thin skin, not on the palms and soles detect stimuli that causes the air to bend, such as an insect landing on your arm
Ruffini endings (bulbous corpuscles)
***6 classes of mechanoreceptors*** are spindle-shaped, slowly adapting receptors found in the dermis, hypodermis, and ligaments respond to stretch and movement
Merkel cell fibers Merkle
***6 classes of mechanoreceptors*** consist of a slowly adapting nerve ending surrounded by a capsule of ____ cells found in the epidermal ridges of the integumentary system. These receptors are found primarily in the skin of the hands, especially the fingertips, where receptor potentials are generated by mechanically gated ion channles
tactile corpuscles (Meissner corpuscles)
***6 classes of mechanoreceptors*** found in the dermal papillae are rapidly adapting tactile exteroceptors transmit discriminative touch stimuli; although their resolution isn't as fine.. more numerous than Merkel
lamellated corpuscles (pacinian corpuscles)
***6 classes of mechanoreceptors*** have a layered onion shaped appearance. These rapidly adapting receptors are found deep within the dermis the layers act like a filter that allow only high frequency vibratory stimuli and deep pressure to activate them
somatic sodium ion channels receptor potential AP
***The basic mechanism of transduction and the way in which sensory receptors respond to stimuli is as follows*** 1) before any stimulus arrives, the ion channels in the axolemma of the ____ sensory neurons are closed. Then the process of transduction begins with for example, pressure on a finger from a probe. 2) when a stimulus such as pressure is applied, mechanically gated ____ open. Sodium ions enter the axoplasm, generating a temporary depolarization redressed to as _____. 3) if enough sodium ions enter that the membrane potential reaches threshold, voltage-gated sodium ion channles open. This triggers an ___, which will be propagated along the axon to the spinal cord
cell body axon central process
***The structure and function of somatic sensory neurons and they areas of skin that these serve, called receptive fields, are found below*** Somatic sensory neurons are pseudo unipolar neurons with the following 3 components 1) the ___ is located in the posterior root (or dorsal root) ganglion, just lateral to the spinal cord. Cell bodies of cranial nerves are found in cranial nerve ganglia located in the head and neck 2) the peripheral process of the neuron is a long ___ that transmits action potentials from the source of the stimulus (a receptor) to the neurons central process 3) the ____ exits the cell body and travels through the posterior root to enter the spinal cord at the posterior horn of the brainstem for cranial nerves where they deliver their action potential
first second third
The basic pathway consist of the following: A _____ -order neuron detects the initial stimulus in the PNS. The axon of this neuron then synapses on a second- order neuron A _____-order neuron, an interneuron located in the posterior horn of the spinal cord or brainstem, then relays the stimulus to a third-order neuron A ____-order neuron, is an interneuron found in the thalamus, delivers the impulse to the cerebral cortex
perception
When the CNS has received all the different sensory inputs from various parts of the brain, it integrates them into a single ____
general somatic senses
______ pertain to skin, muscles, joints, general visceral senses, and those involving the internal senses
perception
a conscious awareness of the sensation
audition gustation olfaction vestibular thalamus olfaction
the special senses include vision, hearing (____), taste (_____) , smell (______), and balance (_____ sensation) each special sense involves neurons that detect a stimulus and sends it to the CNS for processing and integration. The ____ is the gateway for entry of special sensory stimuli into the cerebral cortex, which interprets the majority of this info. ____ is the exception to this rule
posterior columns/ medial leminscal system anterlateral system
two major ascending tracts in the spinal cord carry somatic sensory info to the brain: ______ and _____