Term
| How does the nervous system code for the modality of a stimulus? |
|
Definition
| Modality is a stimulus type. The receptor is sensitive to a specific modality. The neuron will only carry out one modality to consciousness. |
|
|
Term
| How does the nervous system code for the intensity of a stimulus? |
|
Definition
| Intensity is the frequency of neuronal firing. It is coded by the Weber-Fechner law: the more intense of a stimulus, the greater the generator potential and the neuron will fire more frequently. |
|
|
Term
| How does the nervous system code for the location of a stimulus? |
|
Definition
| Locality is the area the stimulus arrives at. The size of the receptive field determines the ability to precisely pinpoint the sensation. |
|
|
Term
|
Definition
| The modality of a stimulus to which a particular sensory receptor is most sensitive. |
|
|
Term
|
Definition
| Afferent neurons plus the receptors it innervates. |
|
|
Term
|
Definition
| Area of the body that, if stimulated, results in activity of that neuron. |
|
|
Term
|
Definition
| Decreases the receptor sensitivity which results in a decrease in action potential frequency. |
|
|
Term
|
Definition
| The sense of posture and position. It is sensory info dealing with the position of the body in space and its parts relative to one another. |
|
|
Term
| Describe the ascending pathways for somatic sensations. |
|
Definition
| Most convey info about a single type of sensory information. They may converge or diverge to interneurons. |
|
|
Term
| Functions of specific ascending pathways. |
|
Definition
| Carry single types of stimuli that pass to the brainstem & thalamus then to specific sensory areas of cortex-somatosensory cortex then to the complex integration areas. (Cross to other side of brain) |
|
|
Term
| Functions of the nonspecific (polymodal) ascending pathways. |
|
Definition
| Activated by sensory units of several different types to indicate something is happening. End in reticular formation and regions of thalamus/brainstem and are not highly discriminative. |
|
|
Term
| Receptor/Graded potential |
|
Definition
| A graded potential produced at the peripheral endings on afferent neurons in response to a stimulus. |
|
|
Term
| Graded potentials characteristics |
|
Definition
| Can be summed, has no threshold, has no refractory period, decrementally, duration varies, initiated by stimulus. |
|
|
Term
| Action potential characteristics |
|
Definition
| Depend on voltage gated channels, can not be summed, has threshold, has a refractory period, constant for all cell types, initiated by graded potential. |
|
|
Term
| Where is the somatosensory cortex located? |
|
Definition
|
|
Term
| What kinds of sensations are perceived in the somatosensory cortex? |
|
Definition
| Information from somatic receptors (receptors in framework or outer walls) |
|
|
Term
| Where is the auditory cortex located? |
|
Definition
|
|
Term
| Where is the visual cortex located? |
|
Definition
|
|
Term
| Function of primary sensory cortex |
|
Definition
| Produces sensation and crude feelings but no interpretation or analysis |
|
|
Term
| Function of sensory association cortex |
|
Definition
| Gives meaning to sensation, interpretation, and perception. |
|
|
Term
|
Definition
| Slow adapting and will continue to fire. |
|
|
Term
|
Definition
| Rapidly adapting and will fire quickly but then stop firing after further stimulation. |
|
|
Term
| How is the sensation of pain created? |
|
Definition
| Pain receptors (nociceptors) are stimulated by chemicals released by damaged tissue then substance P is released to fire neuron and reticular formation/thalamus |
|
|
Term
| What role is played by the enkephalins and endorphins in the perception and appreciation of pain? |
|
Definition
| An enkephalin is a peptide neurotransmitter at some synapses that is activated by opiate drugs and can inhibit pain pathway (Mu receptors) |
|
|
Term
|
Definition
| When visceral pain is referred or is sensed arising from a different somatic location. Why? Pain may be referred due to convergence on the same neuron due to neurons being at the same site or nearby. |
|
|
Term
| How do you focus your eye for near vision? |
|
Definition
|
|
Term
| What muscle is involved in focusing your eye for near vision? |
|
Definition
| Contracted ciliary muscles-slackened zonular fibers |
|
|
Term
| What nervous system is used for focusing your eye for near vision? |
|
Definition
| Firing of parasympathetic nerves (miosis) muscarinic |
|
|
Term
| What is the neurotransmitter used for focusing your eye for near vision? |
|
Definition
|
|
Term
| What is the receptor for focusing your eye for near vision? |
|
Definition
|
|
Term
| How do you focus your eye for far vision? |
|
Definition
|
|
Term
| What muscle is involved in focusing your eye for far vision? |
|
Definition
| Relaxation of ciliary muscle and zonular fibers. Oval shaped radial muscle of iris. |
|
|
Term
| What is the neurotransmitter for focusing your eye for far vision? |
|
Definition
| Norepinpehrine/epinephrine |
|
|
Term
| What is the receptor used for focusing your eye for far vision? |
|
Definition
| Sympathetic beta 2 receptor |
|
|
Term
| How does sound stimulate the hair cells of the organ of Corti? |
|
Definition
| Hair cells have sound receptors so the vibrations open and close potassium channels which send impulses (mechanoreceptors with hairlike sterocilia) |
|
|
Term
| How are these receptors in the Organ of Corti arranged with respect to pitch? |
|
Definition
| Lower pitch- vibrations are further down the cochlea. High pitch- vibrations are closer to the oval window. |
|
|
Term
| What do the semicircular canals monitor? |
|
Definition
| Angular acceleration (rotation) |
|
|
Term
| How does the stimulation of the semicircular canals cause activation of these receptors? |
|
Definition
| Movement of fluid bends the stereocilia and acceleration in release of chemical transmitters from hair cells. Also, this movement causes depolarization (according to direct hyperpolarization or polarization) |
|
|
Term
| What do the utricle and saccule monitor? |
|
Definition
| Linear Acceleration (gravity) |
|
|
Term
| How does this stimulus of the utricle and saccule cause activation of these receptors? |
|
Definition
| Displacement of projecting hairs (covered with otoliths) to move and pull against hair cells so that stereocilia ben and stimulate receptor cells. Stimulated by changes in head position. |
|
|
Term
| Location of somatosensory |
|
Definition
|
|
Term
| Location of visual cortex |
|
Definition
|
|
Term
| Location of auditory cortex |
|
Definition
|
|
