PSY-101 1nd EditionExam # 2 Study GuideConcepts for Exam #2:- Sensation v. Perception o Sensation- process of receiving stimulus energies from external environment.o Perception- the process of organizing and interpreting sensory information.- Brain processes in Perception o Bottom-up processing- information about external environment, goes from sensory receptors to the brain, making sense of information. Emphasizes the important of sensory receptors in detecting the basic features of a stimulus. Moves from part to whole Also called data-driven processingo Top-down processing- starts with cognitive processing at higher levels of the brain Emphasizes importance of observer’s cognitive processes at higher levels of the brain- Emphasizes importance of observer’s cognitive processes in arriving t meaningful perceptions- Moves from whole to part- Also called conceptually driven processing. The use of either can be influenced by cultural differences or nuances, such as found in collectivist vs. individualistic societies.- Transduction in each sense o Transduction- process by which a form of physical energy is converted into a coded neural signal that can be processed by the nervous system.- Absolute Threshold- the smallest amount of stimulus (change) that can be detected- Difference Threshold/just noticeable difference- smallest noticeable difference (how much more do you have to do to notice its effects?)- Weber’s Law o Weber’s law- for each sense the size of a just noticeable difference is a constant proportion to the size of the initial stimulus.- Sensory Adaptation o Attention- selective “Cocktail Party Effect”- we get easily distracted at a party by another person’s conversationo Shiftable Novelty, size, color, movement Stroop effect Change blindness- we do not notice when something has changed in our environment because out attention was selectively shifted elsewhere.o Perception Set Predisposition or readiness to perceive something in a particular way. - Subliminal Perception – detection of stimuli that are below the threshold of conscious awareness; NOT effective on behavior, but CAN BE effective if it is commensurate with goals.- Functions of each part of the eye – anatomy of the eye o Cornea- clear membrane that covers the front of the eye, does most of the focusing of the imageo Pupil and iris- colored part of the eye (iris) and the hole corned by the iris (pupil) Controls the amount of light that enters the eye Aids in controlling the clarity of the image (smaller pupils, clearer image)o Lens- transparent structure behind the pupil Focuses the image on the retina Changes shape to focus on far to near targets through the processes of accommodationo Retina- thin, light-sensitive membrane located at the back of the eye, contains sensory receptors for vision Rods and cones- sensory receptor cells that respond to light- Called Photoreceptors- Exposed to light, rods and cones undergo chemical reactions that result in neural signals.o Cones- most located in the center of the retina Fovea- center of retina with all cones and best vision Responsible for best acuity Responsible for color vision Active at daylight or photo pic light levels About 6 million in the eyeo Rods- located in the periphery of the eye Responsible for night or scout pic vision Have relatively poor acuity Takes approximately 30 minutes to adapt to lowest light levels About 120 million in eye.- Process of vision from eye to the brain - Accommodation in vision - Function of the bipolar and ganglion cells o Bipolar- specialized neurons that collect information from the rods and the cones. They send it to ganglion cells, which sends it to the optic nerve, which goes to the brain.- Blind spot and fovea – what? – where? – function? - Primary and secondary visual pathways - Optic chiasm o After optic nerve and before brain.- Color vision determined by? Three properties of color perception/ o Color Vision Our visual system interrupts differences in the wavelengths of light as color. Rods are color blind, but the cones allow us to see different colors ROYGBIV- Wavelength of about 400 nanometers = violet- Wavelength of about 700 nanometes = red- In between are orange, yellow, green, blue, and indigoo Three properties of color perception are hue, saturation, and brightness- Trichromatic Theory – 3 types of cones o Red-sensitive, green-sensitive, and blue-sensitive. o When a color not in one of those cones strikes the retina, more than one light-sensitive cone is stimulated.- Opponent Process Theory o Green and yellow flago Red-green vs. blue-yellow pairs of color sensitive neurons- What can be explained by each theory of color vision? o Colorblindness- Auditory properties of sound  Loudness- intensity or amplitude of a sound wave, measured in decibels Amplitude- intensity or amount of energy of a wave Decibel- unit of measurement for loudness Frequency- rate of vibration or number of waves per second, measured inhertz Pitch- relative highness or lowness of a sound, determined by the frequency of a sound wave Timbre- distinctive quality of sound, determined by the complexity of the sound wave.- Pathway of sound from environment to the brain o Outer Ear- collects sound waves, consists of pinna, ear canal, and eardrum (lympanic membrane- vibrations cause the membrane to vibrate up and down and the membrane makes contact with the hairs to fire neural impulses).o Middle Ear- amplifies sound waves, consists of three small bones (hammer, anvil,and stirrup)o Inner Ear- where sound is transduced into neural impulses, consists of cochlea (fluid-filled structure containing basilar membrane and hair cells) and semicircular canals.- Functions and anatomy of the parts of the ear - Receptors for sound – what and where? o Embedded in the inner ear inside the basilar membrane are hair cells.- Frequency and Place Theories of pitch  Frequency Theory- basilar membrane vibrates at the same frequency as the sound wave.- Explains how low-frequency sounds are transmitted to the brain Place Theory- different frequencies cause larger vibrations at different locations along the basilar membrane.- Explains how high-frequency sounds are transmitted to the brain- What do these theories explain? o Both theories explain our discrimination of