introduction to cognitive psychology 认知心理学 英文课件.ppt

Introduction to Cognitive Psychology What is Cognitive Psychology? Cognitive psychology is the study of mental processes What is Cognitive Psychology? Cognitive Psychology versus Behaviorism Behavioral Psych: how S maps onto R Cognitive Psych: what happens in the mind Both can use formulas to map S onto R The difference is level of complexity EnvironmentMind S R What is Cognitive Psychology? Cognitive Psychology versus Neurobiology Neurobiology: how does the brain do it? Cognitive Psych: how does the mind do it? Both can use neurons to describe mind The difference is behavior (the big picture) What is Cognitive Psychology? Metaphor: mind = Windows Behaviorists: “What happens when I press Alt-Tab? Cool! It switched to my last open application!” But how does that work? Neurobiologists: “Check this out, the harddrive and the RAM are both connected to the motherboard!” But what does that mean? Cognitive Psychologists: “Pressing Alt-Tab switches me between applications, and I know that Windows uses STM Lets propose a model of Windows where it stores which apps are open in STM, and when a user hits Alt-Tab, it switches between open apps.” What is Cognitive Psychology? Cognitive Psychology versus Artificial Intelligence (AI) AI: whats the best way to do this? Cognitive Psych: how do humans do this? Both try to model some form of mind The difference is fidelity Brain is optimal: If AI truly wants to find optimality they should study Cognitive Psychology. Why study Cognitive Psychology Understanding the mind Education Medicine Therapy Artificial Intelligence Tool/Interface Design Gaming/Entertainment Etc. What is involved in Cognition The book lists: Perception, Attention, Memory, Problem-Solving, Language, Reasoning, language may be part of memory and decision-making, etc. Complexity of Cognition Figure 1.1 (p. 3) - Complexity of Cognition Sarah is walking toward her friend, who is waving in the distance. She is aware of her friend, but has little awareness of the stranger who is passing on her right, even though he is much closer. What we are aware of The complexities of cognition are usually hidden from our consciousness. The Magic of Cognition In our lives we are likely to NEVER encounter the same retinal input twice! EVER! We will learn about categorization and invariant representation The Magic of Cognition The Stroop effect We have automatic reading routines It is hard to stop well-practiced routines from executing This is the difference between experts and novices Figure 1.5 (p 8) - Hemholtzs unconcious inference The display in (a) looks like (b) a gray rectangle in front of a light triangle; but it could be (c) a gray rectangle and a six-sided figure that are lined up appropriately. Complexity of Perception; Expectations The Herring illusion The diagonal lines give the impression of moving forward - the lines look like optic streaks (streaks of neural activation in the retina) When moving forward, straight lines (like doorways) start looking like curves on the retina. Complexity of Perception; Expectations The Magic of Cognition These types of phenomena give us a hint as to how cognition works E.g. Do you process all of the information that falls on your retina? It may be that we have a perfect representation of the world It may be that we make gross estimations based on prior experience DEMO Complexity of Cognition The “understand-the-brain” jigsaw puzzle is particularly daunting To get a sense of the difficulty, imagine a jigsaw puzzle with several thousand pieces. Many of the pieces can be interpreted multiple ways, as if each had an image on both sides but only one of them is the right one. All the pieces are poorly shaped so you cant be certain if two pieces fit together or not. Many of them will not be used in the ultimate solution, but you dont know which ones or how many. Every month new pieces arrive in the mail. Some of these new pieces replace older ones, as if the puzzlemaker was saying, “I know youve been working with these old puzzle pieces for a few years, but they turned out to be wrong. Sorry. Use these new ones instead until future notice.” Unfortunately, you have no idea what the end result will look like; worse, you may have some ideas, but they are wrong. - Jeff Hawkins, On Intelligence Methodology How CogPsych is studied Donders reaction time experiment Figure 1.3 (p. 6) A modern version of Donders (1868) reaction time experiment. (a) the simple reaction-time task; and (b) the choice reaction-time task. For the simple time reaction text, the participant pushes the J key when the light goes on. For the choice reaction time test the participant pushes the J key if the left light goes on, and the K key if the right light goes on. The purpose of the Donders experiment was to determine the time it took to decide which key to press for the choice reaction time test. Figure 1.4 (p. 7) Sequence of events between presentation of the stimulus and the behavioral response, in Donders experiment. The dashed line indicates that Donders measured reaction time, the time between presentation of the light and the participants response. (a) simple reaction-time task; (b) choice reaction-time task. How CogPsych is studied Behavioral and physiological Correction: Figure 1.9 (p. 15) Updated sequence of events between stimulus and response, taking into account the physio- logical response. A, B, Perfors, Tenenbaum, maybe being amused correlates with better memory T