- Is the process of accepting the stimulus by the sense.
Stimulus- is any form of energy that can cause awareness or change to the consciousness (light waves, sound waves, temperature, chemical state – liquid, solid, gaseous, etc.).- These stimuli are then modified and accepted by the accessory structures (eyes, ears, nose, tongue, skin, etc.)
Receptors- are specialized cells responsible for detecting specific type of energy as a result of transduction.- Transduction is the process of changing the stimulus sense into energy for neural activity.
Psychophysics- is the relationship between the physicaland psychological environment. It connectsthe external and internal world of anindividual. Psychophysics aims to examine thesensitivity of the individual to variousstimuli. Then it determines the psychologicalperception on the stimulus.
Absolute Threshold is the least qualityand quantity of a stimulus that can besensed and perceived consequently. It isthe smallest intensity of energy thatcan be perceived 50% of the time. SENSES ABSOLUTE THRESHOLD Light Sees a candlelight 30 miles away on a clear, dark night Sound Hears the tick of a watch 20 feet away under silent situation. Touch Feels wing of a fl 1 cm. away from the cheek Taste Tastes the sweetness of one teaspoon of sugar in 2 gallons of water. Smell Smells the scent of one drop of perfume diffused in a 3-room apartment
Difference thresholdor Just Noticeable Difference (JND) isthe minimum difference in intensitybetween two small stimuli when caused bya smallest change. It does not onlydetermine the presence or absence ofstimulus but also detect whether the twosmall stimuli are different or the same.
Rods- Allow humans to see in black, white, and shades of gray in dim light- Mostly in the periphery- Take 20 – 30 minutes to fully adapt to darknessCones- Enable humans to see color and fine detail in adequate light, but that do not function in dim light- Mostly in the fovea- Adapt fully to darkness in 2 – 3 minutes
Hue is the fundamental color, marked by theintensity of wavelength of the light.Saturation is associated with the purity ofcolor. There are colors that have single,more intense wavelength than otherwavelengths.Brightness conforms to the total degree ofall the wavelengths constituting light.
Coding of Frequencies The auditory system can react tovarious quantities of sound intensities.The greater degree of sound is produced,the more intense is the response of theneuron. The range of specific neuron inthe auditory nerve is based on bothfrequency and intensity of the stimulus.The difference in frequency can beexplained by place theory and volleytheory.
Frequency Theory(Frequency Matching: Volley Theory)William Rutherford pioneered the frequencytheory on pitch discrimination. Themembrane vibrates faster if the tone ishigh. This causes a greater number ofneurons to send the information fasterinto auditory nerve at a particular time.Pitch depends on how fast the stimulus issent to the brain by its frequency persecond.
- Sensations arising from the skin —such as touch, pressure, cold, warmth,and pain — and from the muscles,tendons, and joints — such as theposition of the limbs and pain — areknown as somatic sensations.- All somatic sensations start with theexcitation of sensory receptors locatedin the appropriate tissue — skin,muscle, joints etc.
Gustation- The sensation of tasteFive basic tastes- Sweet- Sour- Salty- Bitter
- Olfaction or the sense of smell issomehow considered to be one of thelower senses.- Odors of gaseous state are senses inthe upper part of the nose. Moleculesenter through the nostrils (Opening) orfrom the back of the mouth (oral cavity)into the nasal cavity. Hence, olfactionis a dual sense; it can smell internally(oral cavity) and externally (nasalcavity).
Proprioception from Latin proprius, meaning "onesown," and perception — is one of thehuman senses. There are between nine and21 in all, depending on which senseresearcher you ask. Rather than sensingexternal reality, Proprioception is thesense of the orientation of ones limbsin space.
a. Vestibular Sense (balance)-the sensations of body rotation and ofgravitation and movement)b. Kinesthesia (posture and movement)-is the perception of body movements. Itinvolves being able to detect changes inbody position and movements withoutrelying on information from the fivesenses.
-The process by which sensoryinformation is actively organized and interpreted by the brain
- Stimulus is recognized by the sense organ – resulting to sensation.- Perception interprets meaningful experiences in totality. The meanings on how the brain organized previous and present knowledge or information are obtained.
Grouping- is when certain elements or objects are put together forming a whole pattern according to the following principles: a. Proximity b. Similarity c. Continuity d. Closure e. Figure and Ground
a. Proximity Proximity occurs when elements areplaced close together. They tend to beperceived as a group.
b. Similarity Similarity occurs when objects looksimilar to one another. People oftenperceive them as a group or pattern.
c. Continuity Continuation occurs when the eye iscompelled to move through one object andcontinue to another object.
d. Closure Closure occurs when an object isincomplete or a space is not completelyenclosed. If enough of the shape isindicated, people perceive the whole byfilling in the missing information.
C. Figure and Ground Figure ground perception is thetendency to discriminate between targetand background stimuli. The stimulus weperceive as being the target is referredto as the figure.
Constancy Constancy is the capacity toperceive stable properties belonging toobjects even if there are changes intheir features. a. Size Constancy b. Shape Constancy c. Texture Constancy d. Color Constancy e. Brightness Constancy
a. Size Constancy Size constancy refers to our abilityto see objects as maintaining the samesize even when our distance from themmakes things appear larger or smaller.
b. Shape Constancy Shape constancy is the tendency toperceive the shape of a rigid object asconstant despite differences in theviewing angle.
c. Texture Constancy Texture constancy reveals the truenature or property of an object. If theobject is closer or nearer, the detailsor features will be visualized. If thesame object is seen farther, it willlook smoother and the details cannot beseen.
d. Color Constancy Color Constancy of the same objectcan vary in accordance with lightillumination. The lightning of an objectcan appear different but its true colorremains the same. A bright lightning ona hue will make the colors appeallighter and less lightning will make thecolors appear darker.
e. Brightness Constancy Brightness constancy refers to ourability to recognize that color remainsthe same regardless of how it looksunder different levels of light.