Sensation, Perception, & Cognition Flashcards
Sense Organs
* Eyes
* Ears
* Nose
* Tongue
* Skin
* Sense of body & space
We have to sense & respond to sensory input
The Senses
Our senses provide us with information about our internal & external environments
Our senses enable people to experience the world
Allows body to respond to changing situations & maintain homeostasis
Sensory experience involves 4 components in the nervous system;
- Stimulus
- Reception
- Perception
- Arousal mechanism
A ___ is a trigger that stimulates a receptor
The meaning depends on reception & processing
i.e. seeing/touching something
stimulus
___ is the process of receiving the stimuli from the nerve endings
Reception
Reception occurs through receptors, such as;
thermoreceptors
proprioceptors, &
photoreceptors
?
Located in the skin, muscles, tendons, ligaments, joint capsules
Nerve endings in skin or body
Coordinate input to enable us to sense the position of our body in space
proprioceptors
?
In the skin and detect variations in temperature
thermoreceptors
?
In retina of the eyes; are what detect visible light & allow us to see and interpret that stimuli
photoreceptors
Components of the Sensory System: ___
___ is the ability to interpret sensory impulses
- Ability to give meaning to impulses
Affected by:
- location of receptor
- # of receptors activated
- frequency of action potentials
- any changes to the above
Perception
99% of stimuli is discarded by the brain
Components of the Sensory System: ___
___ is composed of consciousness and alertness
Mediated by the ___ (___)
Affected by environment, medications
Arousal
reticular activating system (RAS)
?
Located in the brainstem and controls our consciousness and alertness
Neurons make connections between spinal cord, cerebellum, thalamus, & cerebral cortex
Relays visual, auditory, & other stimuli to help keep us awake, attentive, & observant
Without this stimuli, CNS becomes lethargic
reticular activating system (RAS)
Components of the Sensory System: Response
Factors affecting response:
Intensity of stimulus (excites more receptors; i.e. bright vs dim light)
Contrasting stimuli (from cold outside going into garage then into home)
Adaptation to stimuli (nurses accustomed to things in the environment)
Previous experience
This requires people to be alert and receptive to stimulation
What Affects Sensory Function?
Age/Stage of life
Culture (nature, type, & amt of interaction & stimulation; ppl are comfortable w/; preferences in space, eye contact, & touch)
Illness
- i.e. MS slows transmission of nerve impulses
- issues w/circulation like peripheral arterial disease that might impair function of sensory receptors in the brain; can alter our perception & response
- i.e. diabetes ⇒ diabetic retinopathy
- HTN also damages retina of eyes
Medication (aspirin & furosemide that are ototoxic)
Stress
Personality
Lifestyle
Sensory Alterations
Impaired Vision
Impaired Hearing / Smell (anosmia)
Impaired Taste / Kinesthetic Sense / Tactile Perception
Impaired Vision
Affects ALL aspects of daily living
macular degeneration loss of visual field > CVA
orbital trauma
Age-related changes; refractive errors; cataracts; glaucoma; diabetic/hypertensive retinopathy
Signs of Sensory Deprivation
(the state of the RAS depression that is caused by a lack of meaningful stimuli)
- Irritability / confusion / reduced attention span
- Decreased problem-solving ability / drowsiness / depression
- Preoccupation w/Somatic complaints / delusions
High Risk Groups
- Disabled/homebound elders
- Children in orphanages
- Prisoners
- People dealing w/language issues and are unable to interpret in foreign areas
Nursing Interventions: Sensory Deprivation
Focus is on prevention (keep that we are experiencing through our senses the environment around us)
Support the senses (glasses, hearing aids)
Orientation
> Calendar w/current date; view of environment
Provide Stimuli
> Regular contact, touch
> Television, radio
> Pet therapy
> Smells/aromatherapy
Sensory Overload (complex sensory environment [i.e. hospital setting] that contributes to our sensory overload)
Irritability
Confusion
Reduced attention span
Decreased problem-solving ability
Drowsiness
* 1st (5) are same as sensory deprivation
Muscle tension
Anxiety
Inability to concentrate
Decreased ability to perform tasks
Restlessness
Disorientation
Nursing Interventions: Sensory Overload
* Minimize stimuli
> Less light, less noise
> Less television, less bluelight
> Calm tone
> Reduce noxious odors
* Provide rest
* Teach stress reduction strategies
Level of Consciousness
* Indicator of cerebral function
* Most common assessment tool: Glascow Coma Scale (GCS)
* Document objective, specific facts in the nursing notes
* Max score of 15
Nursing Interventions: Clients at Risk for Seizures
* Pad the head, foot, & siderails of bed
* Suction and O2 should be at the head of the bed, readily avail for use
* Do not attempt to open the mouth during a seizure, or try to insert a tongue blade
* Maintain a safe environment for the client
* Turn to side-lying position to avoid aspiration
* Sleep deprivation lowers the threshold for seizures
* Aura stage
* Tonic stage
* Clonic stage
* Postictal stage
