Sensation Fundamentals

Sensation

sensory & nervous system reiche and represent stimulus energies from our enviornment

Perception

process of organizing & interpreting sensory info to make sense of the world around us; involves brains interpretation of sensory inputs

Transduction

conversion of sensory stimuli into neural impulses that can be understood by the brain

Absolute Threshold

minimum amount of stimulation required ti detect a stimuli 50% of the time

Subliminal

below ones absolute threshold for conscious awareness

Just-Noticeable Difference (JND)

the smallest change in stimuli that can be detected by an individual; the minimal difference needed for a person to perceive that change

Weber’s Law

the perceived difference in a stimulus must be proportional to the original intensity; the bigger something is the more change needed

Sensory Adaptation

the process by which sensory receptors become less responsive to constant stimuli over time

Synesthesia

stimulation of one sensory pathway leads to automatic, involuntary experiences in another sensory pathway

Retina

the light sensitive inner surface of the eye, contains photoreceptor cells that convert light into neural signals

Rods

• photoreceptor cells in retina; responsible for vision in low light

• provides black and white vision and his highly sensitive to light allowing vision in dim environments

Cones

• photoreceptor cells in the retina; responsible for color and detail in bright light

• enables us to perceive colors and fine visual details

Fovea

• central area of retina responsible for sharp central vision

• high concentration of cone cells (no rods)

Blind Spot

• area on retina where optic nerve exits the eye; lacks photo receptor cells

• spot where vision is absent

Ganglion Cells

• neurons in retina that receives visual info from bipolar cells & transmits to the brain by the optic nerve

• role in processing visual signals & relays them to the brain for interpretation

Lens

• transparent structure in the eye that focuses

• adjusts its shape to help the eye let in light

Accommodation

• the process by the lens of the eye changes its shape to focus on objects at different distances

• allows for clear vision of nearby & distant objects

Nearsightedness

• close objects appear clear, distant objects appear blurry

Farsightedness

• distant objects are seen more clearly than close ones

Trichromatic Theory