sensory-perceptual development

Examination of how sensory perception and motor skills development intersect throughout life.
Movement is influenced by environmental perception and involves the perception-action model.
- Perception leads to action in order to interact with the environment.

Sensation: Detection of stimuli by sensory receptors.
- Humans possess approximately 33 senses (various sensory modalities).
Focus in this class will be on three primary senses:
- Vision: Involves the eyes and brain.
- Hearing: Involves the ears and brain.
- Kinesthetic Awareness: Involves proprioceptors in the body.
Perception: The interpretation of sensory stimuli by the brain and nervous system.
- Different meanings can be attached to identical stimuli.
- Example: A favorite song may be pleasurable when awake but annoying when tired.

Vision involves both sensory organs (eyes) and the brain's processing abilities.
Development of visual senses requires a combination of clarity and contrast:
- Infants start with blurry vision and can focus on objects about 10 inches away (suitable for caregiver interaction).
- High contrast toys, varied scenery, and colorful books are recommended for visual development in infants.
Visual sensation reaches adult levels by ages 6 to 10.

Shape and Size Constancy: Understanding that objects do not change in size or shape based on perspective.
- Example: A cube looks the same regardless of angle or position.
Figure-Ground Perception: Distinguishing an object from its background. Example: Optical illusions show two images in one.
Whole and Part Perception: Recognizing items as complete or deconstructing them into their parts. Example: A person made of vegetables.
Disparity: Slight differences in images seen by each eye, allowing depth perception.
Spatial Orientation: Understanding how an object is positioned relative to oneself.

Age-related changes in the central and peripheral nervous systems begin around ages 30 to 40, accelerating by 60:
- Neuronal degeneration, gliosis (scarring), lipid accumulation, loss of myelin sheaths, plaque formation in the brain.
- Peripheral changes include altered conduction rates of nerve signals due to myelin loss.
Pathological changes to the eye include:
- Cataracts: Clouding of the lens.
- Diabetic Retinopathy: Blood flow issues to the eyes.
- Glaucoma: Increased intraocular pressure.
- Macular Degeneration: Deterioration of the retina.

Kinesthetic Sensation: Involves proprioceptors that sense body position and movement.
- Found in muscles, tendons, and ligaments.
- Allow recognition of body parts without visual confirmation.
Development progresses from an infant's reliance on oral exploration to advanced motor skills.

Infants exhibit primitive reflexes in response to kinesthetic stimulation (e.g., gripping, reaching).
Children show improvement in sensitivity and precision (e.g., differentiation between fast/slow movements), reaching peak acuity in young adulthood.
Older adults experience decreased kinesthetic and proprioceptive acuity, leading to increased risk of falls due to diminished sensitivity to body positioning and balance.

Newborns are born with poor hearing capabilities due to fluids in the ears.
- Hearing capacity develops significantly by 6 months, reaching adult levels.
Age-related auditory changes result in loss of sensation in older adults due to various auditory organ changes.

Location: Identifying the source of a sound distinct from its environment.
Discrimination of Tone: Ability to differentiate various sounds.
Figure and Ground: Focusing on particular sounds while ignoring background noise (e.g., listening in a crowded restaurant).

Refers to simultaneous perception across multiple senses.
- Earlier theories suggested separate processing of senses; newer models advocate for integrated sensory experiences.
Types of intermodal perception:
- Visual-Auditory: Combining sight and sound (e.g., fireworks with booming sound).
- Visual-Kinesthetic: Combination of vision and movement perception (e.g., dance class).
- Auditory-Kinesthetic: Movement correlated with sound (e.g., hitting a baseball).
Other aspects include spatial-temporal awareness where anticipation of timing and movement is essential (e.g., catching a ball).

In a game of musical chairs, intermodal senses participate in:
- Auditory-Visual: Hearing music tie into visual cues for movement.
- Visual-Kinesthetic: Observing chairs, feeling the seat upon successfully sitting.
- Auditory-Kinesthetic: Moving to the rhythm while listening to music.
- Spatial-Temporal: Adjusting movement based on distance between chairs.

Recognition of the complexity of perception across lifetime stages and its implications for motor skills and overall functioning is vital.
The next lecture will further explore these topics in-depth, particularly focusing on the aging process and its impacts on sensory perception.