Sensory Reception and Perception

Sensory Reception

• Sensory reception involves receiving data from the external or internal environment through senses like vision, hearing, smell, taste, and touch.
• Terms for senses include visual (sight), auditory (hearing), olfactory (smell), gustatory (taste), and tactile (touch).
• Stereognosis is the sense that perceives the solidity, size, shape, and texture of objects.

Internal Orientation

• Internal orientation is achieved through kinesthetic (body part positioning and movement) and visceral (inner organs) senses.
• These senses arise from muscles and hollow organs and form the body's basic orienting systems.
• Proprioception is the subconscious sense of body movement and position, especially limbs, independent of vision, gained from sensory nerve terminals in muscles, tendons, joint capsules, and the vestibular apparatus.

Sensory Perception

• Sensory perception is the conscious selection, organization, and interpretation of sensory data into meaningful information.
• Sensory perception is influenced by stimuli intensity, size, change, representation, past experiences, knowledge, and attitudes.

Requirements for Sensory Experience

• A stimulus capable of initiating a nervous system response must be present.
• A receptor or sense organ must receive and convert the stimulus into a nerve impulse.
• The nerve impulse must travel along a nervous pathway from the receptor to the brain.
• A specific area in the brain must receive and translate the impulse into a sensation.

Conscious States

• Delirium involves disorientation, restlessness, confusion, hallucinations, and agitation, alternating with other conscious states.
• Dementia brings difficulties with spatial orientation, memory, language, and changes in personality.
• Confusion includes reduced awareness, easy distractibility, sensitivity to stimuli, and alternating drowsiness and excitability, resembling a minor form of delirium.
• Normal consciousness means being aware of self and the external environment, well-oriented, and responsive.
• Somnolence means extreme drowsiness, with normal response to stimuli.
• Minimally conscious states include partial consciousness, sleep-wake cycles, some motor function with automatic movements, and inconsistent command following.
• Locked-in syndrome includes full consciousness, sleep-wake cycles, quadriplegia, preserved auditory and visual function, and preserved emotion.
• Asleep individuals can be aroused by normal stimuli like light touch or sound.
• Stupor involves arousal by extreme or repeated stimuli.
• Coma means being unarousable and unresponsive to stimuli.
• Vegetative state includes unarousability, sleep-wake cycles, postures or withdrawal to noxious stimuli, occasional non-purposeful movement, and random smiling or grimacing.

Sensory Deprivation

• Reduced or monotonous sensory input leads to sensory deprivation, impairing the reticular activating system (RAS) function.
• Sensory deprivation can lead to hallucinations for maintaining arousal.
• The COVID-19 pandemic caused sensory deprivation, particularly among nursing home residents.
• High-risk patients include those in environments with decreased stimuli, those with impaired ability to receive stimuli (vision or hearing impairment, bandages), and those unable to process stimuli (spinal cord injuries, brain damage, confusion, medications).

Sensory Overload

• Sensory overload occurs when the brain cannot meaningfully respond to or ignore excessive sensory stimuli, resulting in a feeling of being out of control.
• Sensory overload manifestations may mimic those of sensory deprivation.
• The quantity of stimuli for overload varies based on age, culture, personality, and lifestyle.

Sensory Deprivation Details

• Physical signs and symptoms of sensory deprivation include drowsiness and excessive yawning.
• Escape behaviors from sensory deprivation include eating, exercising, sleeping, or running away.
• Perceptual changes include unusual body sensations, somatic preoccupation, altered body image, illusions, and hallucinations.
• Cognitive changes include decreased attention span, inability to concentrate, and impaired problem-solving.
• Affective changes include crying, irritability, annoyance, confusion, panic, and depression.
• Contributing factors include decreased environmental stimuli (institutionalization, isolation), impaired ability to receive stimuli (sensory impairments, treatments), and inability to process stimuli (spinal cord injuries, brain damage, medications).

Patients at Risk for Sensory Issues

• Institutionalized patients, especially in long-term care, are at risk.
• Patients with communicable diseases (COVID-19, AIDS), those confined to bed, or those with sensory alterations (impaired vision/hearing, eye patches, body casts) are at risk.
• Patients who are depressed, from different cultures, or with nervous system disturbances are at risk.

Nursing Interventions for Sensory Deprivation

• Interventions include increasing sensory stimuli across all modalities to maintain an adequate arousal level.
• Instruct patients in self-stimulation methods like counting, singing, reading, or reciting poetry.
• Structure the environment with meaningful stimuli, including people, ideas, sensations, and pets.

Visual, Auditory, Gustatory, Olfactory, and Tactile Stimulation

• Visual stimulation: colorful sheets, nurse uniforms, face-to-face contact, clocks, pictures, and greeting cards.
• Auditory stimulation: calling the person by name, caring conversations, reading, TV, radio, and iPod.
• Gustatory and olfactory stimulation: oral hygiene, well-fitting dentures, attractive presentation of diverse foods, and smelling food.
• Seasoning preferred foods brought from home is a good intervention
• Tactile stimulation: back rubs, foot soaks, repositioning, range-of-motion exercises, hair care, hugs, and touching arms or shoulders.

Cognitive and Emotional Input

• Cognitive input includes orienting the patient, encouraging self-care, discussing current events/interests, and reinforcing reality.
• Emotional input involves encouraging patients to share concerns, reassuring them about sensory misperceptions, and cultural sensitivity.
• Sensory deprivation must be distinguished from sensory overload, and if adding stimulation increases maladaptive behaviors, sensory input should be reduced

Sensory Overload Details

• Older patients and those with strokes are more prone to confusion or agitation from sensory overload.
• Young patients may seek comfort from parents to block sensory overload.
• Contributing factors for sensory overload are pain, discomfort from intrusive tubes, worry, unfamiliar environments, and intrusive procedures.
• Inability to ignore stimuli, nervous system disturbances, and stimulants leads to sensory overload

Nursing Interventions for Sensory Overload

• Interventions for sensory overload include consistent stimulation patterns to help the patient control their environment.
• Simple explanations, scheduled routine care, calm communication, and slow movements should be employed
• Stimuli, like calls or visitors, should be explored and reduced or minimized through medication or earplugs
• Care must be taken to avoid causing sensory deprivation and eliminating inappropriate stimuli.

Developmental Considerations

• Medically fragile infants benefit from limited light, visual, and vestibular stimulation, simulating the womb environment.
• Play helps develop muscles, coordination, energy release and emotional expression in children

Diagnosing and Addressing Sensory Problems - ICNP

• The International Classification for Nursing Practice (ICNP) identifies problems like impaired cognition, confusion, impaired memory, delirium risk, disorientation, and altered perception as related to sensory function.
• These problems are related to the amount, pattern, or interpretation of incoming stimuli: Visual, auditory, gustatory, olfactory, tactile, or kinesthetic.
• Disturbed sensory perception etiologies include altered environmental stimuli, altered sensory reception, chemical alterations, and psychological stress.
• Outcome identification and planning require nurses to prioritize optimal sensory stimulation and ensure patient outcomes such as living in a stimulating environment, maintaining adequate arousal, demonstrating working senses, scheduling screenings, maintaining orientation, and appropriately responding to stimuli.

Outcomes for Patients with Impaired Sensory Functioning

• Patients should express feeling safe and in control; the patient should describe various types of meaningful stimuli present in the environment.

Vision Changes in Older Adults

• Presbyopia involves loss of elasticity in the eye lens, reducing the ability to focus on near objects and adapt to light.
• Common vision diseases: cataracts, macular degeneration, glaucoma, diabetic retinopathy, hypertensive retinopathy, temporal arteritis, and detached retina.
• Cataracts are the clouding of the crystalline lens resulting in painless, progressive vision loss that can be unilateral or bilateral.
• Macular degeneration is the primary cause of legal blindness; drusen deposits cause central vision loss. Risk factors include smoking, excessive sunlight exposure, fair hair, and blue eyes.
• Glaucoma's are mostly open-angle (95%); increased intraocular pressure causes optic nerve atrophy and visual field deficits.
• Visual changes from Glaucoma include peripheral vision loss, glare intolerance, decreased contrast, and adapting to dark changes.
• Diabetic retinopathy involves end-organ damage from diabetes, causing retinopathy and spotty vision. Tight blood sugar control helps reduce the risk.
• Hypertensive retinopathy involves end-organ damage from uncontrolled hypertension, treated by laser photocoagulation and blood pressure control.
• Temporal arteritis is an autoimmune disorder causing temporal artery inflammation, malaise, scalp tenderness, headache, jaw claudication, and sudden vision loss. It is of medical emergency with possible reversible implications
• Detached retina can occur in patients with cataracts, recent surgery, trauma, or spontaneously resulting in a "curtain" across vision, mandating immediate ophthalmologist consultation or emergency room visit.