Introduction to Cognitive Processes. (Information Processes)

1. Sensation and Perception We receive and deal with information around us through a chain of events known as sensory information processing. The first part of this process is SENSATION. It is defined as the activation of sensory receptors by physical stimuli and the processing of and transmission of neural signals to thebrain. Sensation represents the early stages of information processing. Sensations result from the processes associated with organs These senses include, vision, audition, olfaction (smell), gestation (taste), the skin sense (including pressure, temperature, and pain) and the body sense (including our sense of orientation and body movement).. Introduction to Cognitive Processes. (Information Processes) WWW.SMSO.NET

2. However, this process (the chain of events) is continuous, but psychologist use to break it into sensation and perception. Our sensory system, which consists of different sensory modality, brings information from the external world. Each sensory modality, or system, has specialized receptor cells, designed to detect a particular form of energy and to filter incoming information. TRANSDUCTION: They convert the energy stimuli into neural activity through the process of TRANSDUCTION: the conversion of sensory stimulus into neural activities, e.g., visual receptors transduce light energy. So the language of communication of sensory receptors, as in any other cells, is neural signals. (impulse). WWW.SMSO.NET

3. PSYCHOPHYSICS: The relationships between the physical stimulus’ characteristics and sensory responses Absolute Threshold: sensory systems are characterized by their sensitivity to variation in stimulation, i.e., their differential responsiveness to variations). Some of these variations are so weak that our sensory system cannot detect. They don’t stimulate us.??? E.g., we don't notice radio waves, x-rays, or the microscopic parasites crawling on our skin.  Psychologists are interested in studying the weakest amount (intensity) of stimulus that our sense can detect. Absolute Threshold Sensitivity to INTENSITY is measured by absolute threshold, It is defined as THE MINIMUM AMOUNT OF STIMULUS ENERGY THAT CAN RELIABLY BE DETECTED.) The absolute threshold is the point where something becomes noticeable to our senses.  It is the softest sound we can hear or the slightest touch we can feel.  Anything less than this goes unnoticed.  The absolute threshold is therefore the point at which a stimuli goes from undetectable to detectable to our senses THRESHOLDS: WWW.SMSO.NET

4. Difference Threshold Sensitivity to a change in intensity is measured by the difference threshold (THE MINIMUM DIFFERENCE BETWEEN TWO STIMULI THAT CAN BE RELIABLY DETECTED Once a stimulus becomes detectable to us, how do we recognize if this stimulus changes The difference threshold is the amount of change needed for us to recognize that a change has occurred.  This change is referred to as the Just Noticeable Difference ( j.n.d) Difference Threshold This difference is not absolute because the change required to detect a difference has to represent a percentage. This theory, named after its original observer, is referred to as Weber's Law. The amount of change needed for detection to occur increase with the initial intensity of the stimulus, and is approximately proportional to it (WEBER’S LAW). Difference Threshold WWW.SMSO.NET

5. The last concept refers to stimuli which has become redundant or remains unchanged for an extended period of time. Why we notice certain smells or sounds right away and then after a while they fade into the background? Once we adapt to the perfume or the ticking of the clock, we stop recognizing it. This process of becoming less sensitive to unchanging stimulus is referred to as sensory adaptation, after all, if it doesn't change, why do we need to constantly sense it? Sensory adaptation allows us to react quickly to any change of stimulus once our sense is exposed to a constant, unchanging level of stimulation. Adaptation is the change in sensitivity in response to a constant level of stimulation. SensoryAdaptation WWW.SMSO.NET

6. PERCEPTION • PERCEPTION • The second part of this chain is PERCEPTION, which represents the processes of organization and interpretation made by the brain to the sensory signals, to produce a MENTAL REPRESENTATION of the original stimuli. • This is based on: • (a) Sensory Input] & • (b) Knowledge/(experience), so it can create representation of objects an events. WWW.SMSO.NET

7. FUNCTIONS OF PERCEPTION: • FUNCTIONS OF PERCEPTION: • Basic question: What is the importance of our perceptual system to our life? Its Functions? • The main function is related to: • (1) the determination of what is that thing or object which we are perceiving?, (pattern- or object- RECOGNITION), and • (2) Where is it?, its location and distance in the space (LOCALIZATION WWW.SMSO.NET

8. PERCEPTUAL ORGANIZATION • BASIC TO BOTH RECOGNITION AND LOCALIZATION IS THE PROCESS OF PERCEPTUAL ORGANIZATION • Perceptual organisation requires some important process including • Attention • Visual segregation, and Grouping WWW.SMSO.NET

9. Recognition of objects goes through two main stages. a) EARLY STAGE OF RECOGNITION: 1) This is the stage in which the visual system uses retinal information to describe objects in terms of feature like line, edges, curves, and angles. Cells to detect and analyze these features are referred to as FEATURES DETECTORS. Some of these have been found in the visual cortex. 2) Much of the information about this came from studies on single cell recording in the visual cortex, which examined the sensitivity of specific cortical neuron when different stimuli are presented to the receptive field of a cortical neuron. Hubel and Wiesel (1959), who discovered thee types of these feature detectors pioneered these studies. The thee types of cells are simple cells. Complex cells and Hyper-complex cells. 3) The process of feature analyses goes almost simultaneously with the process of visual segregation. Recognition of Objects WWW.SMSO.NET

10. LATTER STAGE OF RECOGNITION • MATCHING: • 1) In this, we can see how the description of the object, based on early stage of feature detection and visual segregation, is MATCHED to a shape stored in the visual memory. So this is the stage of matching. • 2) The connectionist model, or the model of parallel processing can explain matching. This model also explains what we refer to as Bottom-Up and Top-Down processing of information. WWW.SMSO.NET

11. LOCALIZATION • LOCALIZATION • It represents the skills and abilities which help us to navigate and move around. Without it we would constantly bump into objects • To localize and recognize objects, our perceptual system undergoes several processes. In executing these processes we rely on several senses (e.g., distance senses: represented in VISION AND HEARING). • Localizationalso requires several other cognitive processes. We need first to ATTEND to the objects, so Attentional process (including focused and selective) is important. • Segregation of objects from one another and from its background is another important process in localization. • Finally we have to organize them into groups. • So Segregation & Organization are important processes to localization and recognition of objects. WWW.SMSO.NET

12. PERCEPTUAL ORGANIZATION • Gestalt Principles of Grouping • The German word “GESTALT" roughly translates to "whole" or "form," and the Gestalt psychologist's sincerely believed that the whole is greater than the sum of its parts.  • In order to interpret what we receive through our senses, they theorized that we attempt to organize this information into certain groups.  This allows us interpret the information completely without unneeded repetition.  For example, when you see one dot, you perceive it as such, but when you see five dots together, you group them together by saying a "row of dots."  Without this tendency to group our perceptions, that same row would be seen as "dot, dot, dot, dot, dot," taking both longer to process and reducing our perceptive ability.  • The Gestalt principles of grouping include four types: similarity, proximity, continuity, and closure. WWW.SMSO.NET

13. Similarity refers to our tendency to group things together based upon how similar to each other they are.  • In the first figure above, we tend to see two rows of blue dots and two rows of black dots.  The dots are grouped according to similar color.  • Proximity: In the next figure, we tend to perceive three columns of two lines each rather than six different lines.  The lines are grouped together because of how close they are to each other, or their proximity to one another. • Continuity refers to our tendency to see patterns and therefore perceive things as belonging together if they form some type of continuous pattern.  In the third figure, although merely a series of dots, it begins to look like an "X" as we perceive the upper left side as continuing all the way to the lower right and the lower left all the way to the upper right.  • Finally, in the fourth figure, we demonstrate closure, or our tendency to complete familiar objects that have gaps in them.  Even at first glance, we perceive a circle and a square. WWW.SMSO.NET

14. Perceiving Distance We determine distance using two different cues: monocular and binocular. Monocular cues are those cues which can be seen using only one eye.  They include size; texture, overlap, shading, height, and clarity.   Binocular cues refer to those depth cues in which both eyes are needed to perceive. There are two important binocular cues; convergence and retinal disparity. Convergence refers to the fact that the closer an object, the more inward our eyes need to turn in order to focus.  The farther our eyes converge, the closer an object appears to be.  Since our eyes see two images which are then sent to our brains for interpretation, the distance between these two images, or their retinal disparity, provides another cue regarding the distance of the object.  DEPTH PERCEPTION WWW.SMSO.NET

15. ILLUSTRATIONS ON VISUAL ILLUSION Which vertical line  is longer WWW.SMSO.NET

16. Can you guess this woman's age? Keep looking at the picture WWW.SMSO.NET

17. Do you see both pictures in A, B, and C?  Do they change? WWW.SMSO.NET

18. Depth Perception IMPOSSIBLE IMAGE WWW.SMSO.NET

19. Human Memory • Memory is central to all cognitive function and to all human behaviors. It is the process that follows the perception of current information for later use. • Many psychologists agree with the dominant theory stating that there are at least two memory systems: SHORT TERM MEMORY (STM), and LONG TERM MEMORY (LTM). • These are also preceded by an initial stage of sensory memory. • According to this theory, information must passed first through STM, in which information is held for fairly short intervals, and then get to the LTM in which information is stored for much longer time. • Within each of the two main systems (STM & LTM) information is to be processed through several stages including encoding, storing, and retrieval. So any act in remembering implies success in these three phases WWW.SMSO.NET

20. MODELS OF MEMORY • So the most accepted model states that there are three stages of memory storage:  SENSORY STORE, SHORT-TERM STORE, and LONG-TERM STORE. • SENSORY MEMORY • sensory store retains the sensory image for only a small part of a second, just long enough to develop a perception. • Iconic memory for visual stimuli, • Echoic memory for aural stimuli • Haptic memory for touch. WWW.SMSO.NET

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22. Human memory, like memory in a computer, allows us to store information for later use. In order to do this, however, both the computer and we need to master three processes involved in memory. The first is called ENCODING; the process we use to transform information so that it can be stores. For a computer this means transferring data into 1’s and 0’s. For us, it means transforming the data into a meaningful form such as an association with an existing memory, an image, or a sound. Next is the actual STORAGE, which simply means holding onto the information. For this to take place, the computer must physically write the 1’ and 0’s onto the hard drive. It is very similar for us because it means that a physiological change must occur for the memory to be stored. The final process is called RETREIVAL, which is bringing the memory out of storage and reversing the process of encoding. In other words, return the information to a form similar to what we stored. PROCESSES OF MEMORY WWW.SMSO.NET

23. SHORT TERM MEMORY: 1) Different terms are used to refer to STM, but each with its connotation. IMMEDIATE MEMORY, & WORKING MEMORY. 2) Immediate Memory: This could be considered as the first stage of STM, temporarily holds information retained from the registration process. 3) When the term working memory is used for this system, it’s mainly used to consider it as a central processing unit of information. SHORT-TERM MEMORY (STM)takes over when the information in our sensory memory is transferred to our consciousness or our awareness). This is the information that is currently active such as reading this page, talking to a friend, or writing a paper. Short term memory can definitely last longer than sensory memory (up to 30 seconds or so), but it still has a very limited capacity. According to research, we can remember approximately 5 to 9 (7 +/- 2) bits of information in our short term memory at any given time (Miller, 1956) SHORT TERM MEMORY WWW.SMSO.NET

24. 1) ENCODING: Information in STM tends to be encoded acoustically. Although we can use visual code, we prefer the acoustic one. E.g. phone number 2) We favour the verbal acoustic coding when we try to keep information active by Rehearsing it, i.e., by repeating over and over to ourselves. During STM encoding, the brain organizes information into CHUNKS (the largest possible cluster it can recognize as a familiar pattern). 3) STORAGE: Perhaps the most striking fact about STM is that it has a very limited capacity. On the average, the limit is (7+_ 2). There are however, some individual differences, probably due to long term memory or the use of chunking. 4) FORGETTING: When the limits of STM is reached, a form of forgetting occurs: a) A new item can enter STM only by DISPLACINGan old one. b) The other major cause of forgetting in STM is that information DECAYS with time. So storage failure when exceeding the capacity. Process in STM WWW.SMSO.NET

25. PROCESSES IN LTM • 1) ENCODING: information in LTM is encoded SEMANTICALLY, that is to its meaning. • 2) STORAGE: the process of storing information as LTM (CONSOLIDATION) may occur quickly or continue for consolidation time. If the item to be remembered are meaningful but the connection between them are not, memory can be improved by adding meaningful connections. This is called ELABORATION..: • Maintenance Elaboration • Semantic Elaboration • Capacity of LTM store: unlimited WWW.SMSO.NET

26. Many cases of forgetting in LTM are due to Retrieval Failure; that is, the information is there but cannot be found. Retrieval failure is more likely to occur when there is INTERFERENCE from items associated with the same retrieval cues. Retrieval failure is less likely to occur when the items are organized during encoding and when the context at retrieval is similar to that at encoding. Retrieval process can also be disrupted by Emotional Factors. Some forgetting from LTM is due to loss from storage, particularly when there is a disruption of the process that consolidate new memories. Consolidation takes place in the hippocampus and the amygdala. Recent research suggests that consolidation may take a matter of few weeks Forgetting in LTM WWW.SMSO.NET

27. MEMORY MODEL WWW.SMSO.NET

28. LONG TERM MEMORY DECLARATIVE MEMORY (EXPLICIT) PROCEDURAL MEMORY (IMPLICIT) EPISODIC (Events) Where did you park your car SEMANTIC (Meaning) (What is the capital of S.A) Driving a Car WWW.SMSO.NET

29. Long-term memory Long-term memory is intended for storage of information over a long time. Information from the working memory is transferred to it after a few seconds. Unlike in working memory, there is little decay. There are two types of long-term memory: episodic memory and semantic memory. Episodic memory represents our memory of events and experiences in a serial form. It is from this memory that we can reconstruct the actual events that took place at a given point in our lives. Semantic memory, on the other end, is a structured record of facts, concepts and skills that we have acquired. The information in semantic memory is derived from that in our own episodic memory, such that we can learn new facts or concepts from our experiences. OTHER CLASSIFICATION OF LTM WWW.SMSO.NET

30. MORE ABOUT MEMORY • Explicit memory refers to the kinds of memory manifested in recall or recognition. when we consciously recollect the past. • Implicit memory refers to the kind of memory that manifest itself as an improvement on some perceptual, motor, or cognitive tasks with no conscious recollection of the experience that led to the improvement. Amnesic deficits concern explicit but not implicit memory. • Explicit memory breaks with Amnesia, while implicit memory doesn’t. This suggests two separate systems of storage. • Procedural knowledge refers to KNOWING HOW. How to drive a car. • Declarative Knowledge is related to “KNOWING THAT”: for example knowing that cars run on gasoline. WWW.SMSO.NET

31. There are two types of information retrieval: recall and recognition. In recall, the information is reproduced from memory. In recognition the presentation of the information provides the knowledge that the information has been seen before. Recognition is of lesser complexity, as the information is provided as a cue. However, the recall can be assisted by the provision of retrieval cues which enable the subject to quickly access the information in memory RECALL AND RECOGNITION WWW.SMSO.NET

32. FORGETTING • Ineffective initial encoding, usually occurs because of ineffective attention in the acquisition phase • DECAY:  forgetting occurs because memory fades with time. • INTERFERENCE: forgetting occurs because of competition from other information • Retroactive Interference: new information interferes with what has already been learned • Proactive Interference: old information interferes with what is being learned • RETRIEVAL FAILURE: sometimes we can not remember something which at another time we can remember it; perhaps this is because of the context cues or retrieval cues present at the time • motivated forgetting:  we may tend to forget things that we do not wish to remember (Freud) (Repressed Memories ) • BRAIN INJURY: • ANTEROGRADE AMNESIA (injury prevents new memories from occurring): • RETROGRADE AMNESIA: (injury prevents old memories from occurring) WWW.SMSO.NET

33. Thinking an Reasoning • Thinking includes a wide range of mental activities. It is the language of our mind, and it can be presented in different ways or modes. These include: Propositional Thought, Imaginal thought, and the Motoric thought. • (I) PROPOSITIONAL THINKING: • 1) Three important aspects of proposition thinking can be studied: its Content, its Organization, and its way of Communication. • 2)Content : refers to how we form or build blocks of thought and how we use them to classify objects. • -This is done through the development of CONCEPT FORMATION. • -A concept is a set of properties that we associate with classes of objects. It is the basis of categorizing items to their shared properties, e.g. classes of antibiotics, or antipsychotic. It also helps us to predict information that is not accessible to us, e.g. a cat, a lion etc. WWW.SMSO.NET

34. PROPOSITIONAL THINKING • 3) Organizationof thought refers to the ways and types of reasoning we use. In reasoning our sequence of thoughts often take the form of an argument, in which one proposition correspond to a Conclusion, and the remaining correspond to the premises. • - There is two type of reasoning: Deductive, and inductive reasoning. • - Deductive reasoning are the strongest types of logical reasoning. It means that it is impossible for the conclusion of an argument to be false if its premises are true. Here we go from the general to the specific; we deduce a particular consequence from set of general rules, we Infer the conclusion from the premises. • - Inductive reasoning represents the reversed process of reasoning; here we try to induce a general rule from particular premises. Here it is improbable that the conclusion is false if the premises are true. WWW.SMSO.NET

35. 4)Communicatingour Thoughts is achieved through language. Languages are organized as a hierarchy of structures. The highest level is SENTENCE UNITS, including phrases that can be related to units of proposition. The phrases of a sentence are built of words, or parts of words that have meaning, Next level is that of WORDS and parts of words that carries meanings a MORPHEME. Morphemes are words, suffix or prefix that are added to words. The lowest level contains SPEECH SOUNDS. A phoneme is a category of speech sounds. Every language has its own set of phonemes and rules that combining them into words. Communicating our Thoughts WWW.SMSO.NET

36. Understanding and Expressing LANGUAGE • A language also has syntactic rules for combining words into phrases and phrases into sentences. • Producing language is a process of translating propositional thoughts into the phrases and morphemes of the sentence, and then translating this into phonemes. • PHRASES-------- MORPHEMES------- PHONEMES • Understandinga sentence requires not only analyzing phonemes, morphemes, and phrases, but also using the context and understanding the intention of the speaker. In understanding language the process is reversed. That is, we use phonemes to construct morphemes, and then phrases • TYPES OF APHASIA WWW.SMSO.NET

37. IMAGINAL THOUGHTS: 1) Not all types of our thoughts are presented in proposition. Some are presented in visual images. Such images contains the kinds of details found in visual perception 2) Imagery can be like perception because it is mediated by the same part of the brain. Thus, brain damage that results in certain perceptual problems, e.g., visual neglect, also results in comparable problems in imagery. THOUGHTINACTION:PROBLEMSOLVING: 1) Problem solving involves decomposing a goal into subgoals that are easier to obtain. 2) We use different strategies to solve daily problems That why experts are superior to novice in problem solving. The IDEAL problem solver refer to effective strategy and planning for problem solving. OTHER TYPES OF THINKING WWW.SMSO.NET