PSYCH 322- 1st Edition Lecture 6Chapter 3Outline of Last Lecture I.Perception, Attention, Short-Term and Working MemoryII.Questions to considerIII.Bottom-up & Top-down processingOutline of Current LectureIV.Illustrating top-down processingV.Perception VI.Helmholtz’s Theory of Unconscious InferenceVII.Gestalt’s perceptual organizationVIII.Heuristic: “rule of thumb”IX.Neurons and the environmentX.Perception and ActionCurrent LectureI.We started off lecture today recapping on the Bosnian Language we ended with last class. We as humans are biologically predisposed to figure out language. At 2 or 3 years of age, without taking a Language arts or English class, we figure out our stream of speech. We talked about Speech Segmentation: the process of perceiving individual words within the continuous flow of the speech signal, which is a top-down form of processing. II.Another thing we talked about was pain stimulus and the placebo effect. We usedthe example of a burn victim in the hospital getting his bandages changed. This is a very painful process and the hospital wanted to shift his attention from the bandages into a virtual reality world. The patient wore a black plastic helmet containing a computer monitor which he saw a virtual world of multicolored 3D graphics. This 3D world placed him in a virtual kitchen that contained spiders that he was able to chase into the sink so he could grind them up with a virtual garbage disposal. The patient reported that because he was concentrating on something other than pain, that his pain level decreased significantly. This demonstrates how expectation and attention can influence a person’s experience of pain.These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.a.The placebo effect works by having one group of individuals who gets nothing,one group who receives a drug trial, and one group who gets a fake pill and informed on the effects of the drug they “received” and they compare the results of the three groups. This proved that the belief or expectation that youhave been treated can make you report belief, even if you didn’t receive a drug. III.Definitions:a.Sensation: absorbing raw energy through our sensory organsb.Transduction: conversion of this energy to neural signalsc.Attention: concentration of mental energy to process incoming informationd.Perception: selecting, organizing, and interpreting these signalsi.The process of recognizing, organizing, and interpreting information from our senses. It is based on out past experiences and expectations.IV.Sensation & Perception: energy contains information about the world, receptors transduce energy into neural responses, sensory nerve transmits the coded activity to the central nervous system, thalamus processes and relays the neural response which is relayed to specialized areas of the cortex, and our perception of the world is created. V.Perception:a.Direct perception theories: (bottom-up processing)i.Perception comes from the stimuli in our environment that is now information put into our system. ii.Parts are identifiable and put together, and then recognition occursiii.We perceive objects by perceiving elementary features. Objects are recognized when enough information is available to identify itb.Constructive perception theories: (top-down processing)i.We impose information onto the environmentii.People actively construct perceptions using information based on expectationsiii.We make inferences based on context, guessing from experience, and basing one perception on anotheriv.This occurs quickly and automaticallyc.The blob figure (3.11) in our textbook. i.You can perceive this blob as many different things because it is a blurry section of a picture. In this figure they placed the figure as a component in 3 different scenes and we are able to perceive the same blurred image in 3 different situations. ii.Changing the perspective of an object or objects in motion change the way we perceive. iii.Top-down processing takes stimulus that we know exists and processesit into what is probable1.Example: You are in a hotel room and it is dark. You see an object on the bedside table that you can’t make out. Your brain begins to figure out what probable things you normally find on a bedside table, and you are able to perceive that it is a lamp.d.Perceiving size is a function is both bottom-up and top-down processing:i.Bottom-up : the size of the image on the retinaii.Top-down: the perceived distance of the object and the size of the object relative to other objects in the environment.VI.Helmholtz’s Theory of Unconscious Inference: top-down theorya.We use our knowledge to inform our perceptions which are the result of unconscious assumptions we make about the environment.b.We infer much of what we know about the worldc.Likelihood principle: we perceive the world in the way that is “most likely” based on our past experiences.VII.Perceptual organization: Gestalts heuristic lawsi.“old” view- structuralism: perception involves adding up sensationsii.“new” view- Gestalt psychologists: the mind groups patterns according to laws of perceptual organizationb.Law of good continuation: overlapping lines perceived as continuous interwoven strands because of good continuationc.Law of good figure or simplicity: every stimulus pattern is seen so the resulting structure is as simple as possiblei.Example: 5 Olympic rings – we know that it is just 5 overlapping circles,not a complex array of 9 objectsd.Law of similarity: similar things appear grouped togethere.Law of familiarity: things are more likely to form groups if the groups appear familiar or meaningfulf.Law of proximity: things near each other appear grouped togetherg.Law of common fate: things moving in the same direction appear to be grouped togetherh.These laws often provide accurate information about properties of the environment (reflect experience, used unconsciously, occasionally misleading)VIII.Heuristic: “rule of thumb”i.Fast mental shortcutsii.Provides a best-guess solution to a problem that is often correctb.Algorithm: a slow procedure guaranteed to solve a problem with a definite resultc.Perceptual Heuristicsi.“light-from-above”- in the environment, light usually comes from above. We perceive shadows as specific information about depth and distance.d.Occlusion heuristic: when