Introduction to Cognitive Processes. (Information Processes)

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Introduction to Cognitive Processes.
(Information Processes)

• 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 the
  brain.
• 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)..

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• 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).

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THRESHOLDS

• 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 dont
  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

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Difference Threshold

• 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
  (WEBERS LAW).
•  

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Sensory Adaptation

• 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.

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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.

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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

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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

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Recognition of Objects

• 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.

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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.

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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).
• Localization also 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.

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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.

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• 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.

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DEPTH PERCEPTION

• 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. 

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ILLUSTRATIONS ON VISUAL ILLUSION

• Which vertical line  is longer

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• Can you guess this woman's age? Keep looking at
  the picture

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Do you see both pictures in A, B, and C?  Do they
change?
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Depth Perception
IMPOSSIBLE IMAGE
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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

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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.

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PROCESSES OF MEMORY

• 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 1s and 0s. 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 0s 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.

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SHORT TERM MEMORY

• 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, its 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)

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Process in STM

• 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 DISPLACING an
  old one.
• b) The other major cause of forgetting in STM is
  that information DECAYS with time.
• So storage failure when exceeding the capacity.

• 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).

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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

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Forgetting in LTM

• 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

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MEMORY MODEL
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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
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OTHER CLASSIFICATION OF LTM

• 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.

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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 doesnt. 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.

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RECALL AND RECOGNITION

• 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

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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)

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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.

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PROPOSITIONAL THINKING

• 3) Organization of 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.

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Communicating our Thoughts

• 4) Communicating our 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.

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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
• Understanding a 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

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OTHER TYPES OF THINKING

• 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.

• THOUGHT INACTION PROBLEM SOL VING
• 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.