Psych Final Study Guide SENSATION PERCEPTION Sensation vs Perception o Sensation o Perception Detection of raw sensory info from the environment Able to detect with your senses Ex Light activates cells in the retina Sounds waves create vibrations in the ear Understanding sensory info as meaningful categories Perception is an act of creation Make meaning out of the information Ex tastes like chicken that s my moms face Five Basic Senses vs Sixth Senses o 5 Basic Senses vision hearing smell taste touch o Sixth Senses Balance body orientation Kinesthesia body motion Proprioception limb position Interoception internal organs Sensory Transduction electrical impulses o In order to sense the world you must translate physical realties into neural Vision photons of light Hearing vibrations in the air Taste Smell chemicals in air water and food Touch pressure temperature vibration Gate Control Theory of Pain pain may be reduced by increasing other pleasant stimulations ex rubbing sucking putting ice on it Sensory Thresholds Absolute Threshold minimal amount detected Difference Threshold the amount something has to change in order to be noticed Bottom up vs Top down o Bottom up Processing senses detect stimuli in the environment Ex vision shape color motion hearing frequency amplitude o Top down Processing perception influence by prior knowledge and expectations filling in o perceptual visions are compensated for missing info o makes it easier to perceive an image if we see what we expect to see o may cause one to see something that is not really there Perception involves how the mind organizes and groups patterns of Evidence for Top down Processing o Gestalt Principles sensations 1 Similarity Similar things appear grouped together you see columns of the same color instead of rows of alternating colors 2 Continuity Lines tend to be seen as following the smoothest path 3 Closure or Simplicity patterns are seen so the resulting structure is as simple as possible we see an upside down triangle even though it is not really there 4 Figure ground organize perceptions by distinguishing between a figure and a background o Context Effect describes the influence of environmental factors on one s perception of a stimulus the same object can be perceived differently depending on the context o Shape size color constancy Shape object s shape appears to remain the same even thought the visual image changes Ex a door opening and closing Size object s size seems constant despite the size of the raw visual image distance may effect image Color perception of color is relative and may change within context however color is constant Ex stop sign is red all day and all night o Hearing words in sounds The sounds of speech are not clearly differentiated into words Sound waves may be continous but our minds know how to break it up into words Ex I scream for ice cream o Sine Wave Speech Distorted versions of speech that can be understood only if heard a clear version of the same speech Ex hear someone mumble cannot understand hear them say it clearly then mumble again able to hear it o McGurk Effect Perception of language phonemes may be altered by visual cues What we see overrides what we hear Ex someone says ball but if we see them say f with their mouth we hear fall instead Attention Needed in order for sensations to become perceptions Perception is selective because attention is selective o Overt vs Covert Overt directed attention someone else tells you to look at something Covert when attention is grabbed by something that wasn t directly payed attention too Ex you hear a loud sound and then look for the source o Selective Attention The ability to focus on one message and ignore all others we tend to pay attention to things that we expect in the environment and filter out other information ex focusing on studying o Inattentional Blindness Lack of attention to an obvious stimulus results in heavily focusing attention on another task ex basketball video with bear in the background dancing o Change Blindness When shown different versions of a scene differences between them are not immediately apparent we can be blind to changes that occur right in front of us because we were not looking for it or focusing our attention on it ex people change outfits in the same scene of a video Seeing without Seeing o Blindsight Ability to sense visual information without the ability to see it Eyes work fine blindness due to brain damage Ex could point in the direction of light Could avoid objects in their way o Visual Agnosias Inability to recognize specific categories of objects Vision is intact but unable to identify what an object is Ex objects places body parts animals o Prosopagnosia Visual agnosia specific to faces May be able to identify any other object except for faces Perception as Constructions we construct out perceptions you don t see the world as it is you see it how you made it o Visual perception built piece by piece Eyes are constantly moving in saccades one piece of visual info at a time Specialized visual areas of the brain Primary feature detectors ex basic shapes motion color Association areas ex recognize faces bodies objects animals MEMORY Sensory Memory system that briefly stores all incoming sensory information o Iconic vs Echoic Iconic visual sensory memory lasts about 1 sec can store up to 12 images pre categorical Echoic auditory sensory memory 2 3 seconds to enable processing Short term Memory stores small amounts of information for a brief duration working memory manipulating How many numbers someone can hold in memory Typically 5 8 George Miller s magic 7 2 o Digit Span o Chunking Small units can be combined into larger meaningful units A collection of elements that are strongly associated with one another but weakly associated with elements in other chunks o Primacy vs Recency Primacy better memory for info at the beginning of list Recency better memory for info at the end of list Long term Memory storage stretches from a few months ago to as far back as one can remember memories may fade or change over time can be confused with others o Explicit Declarative Memories that can be explained and described episodic personal semantic facts both affect differently can have one w o the other o Implicit Non Declarative Memories that cannot be explained and described procedural memory for skills experience execute action ex riding a bike priming conditioning memory for assumption ex yellow vehicle school