Cognitive processes

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Cognitive processes
Engineering Psychology

• perception sensation attention thinking
  imagination memory creativity problem
  solving

Jakub Jura Jakub.jura_at_fs.cvut.cz http//users.fs.c
vut.cz/jura/ing-psych/
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What is Cognitive?

• From latin cognoscere getting to know
• Distinguish emotional and rational
• Descartes Cogito ergo sum.

Mental processes mediate between stimulus and
response.
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Cognitive processes

• Base Cognitive processes
• Perception
• Sensation
• Attention
• Thinking
• Imagination
• Memory
• Learning
• Advanced Cognitive processes
• Creativity
• Problem solving

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Sensation

• Sensation is about sense organ and basic
  processes on this level.
• Perception is about creating whole percept.

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Sensation
Perception Percept Sence Organ
Visual Perception Image Eye
Auditive Perception Sound Ear
Gustatory Perception Taste Taste Buds
Olfactory Perception Smell Nose
Haptic Perception Touch on skin Nociceptors
Proprioception Body position Proprioceptor
Human Feromon Affection / antipathy Vomero-Nasal Organ
Magnetoception Impression of north Unknown
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Haptic sensibility

• Tactile compasses
• The brain projection zone.
• Skin surface and brain surface.

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Sensation Delusions
Lateral Inhibition Efect

• Machs Strips

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Blind spot

• Close the right eye. Leave your head in the
  central position.
• Look to the cross, by the left eye.
• Approach your head to the paper.
• The circle disappears in a given distance.

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Negative afterimage
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Perception

• Perception is perception of diference.
• Sensuals limits
• Gestalt law
• Multistable figures
• Invariance in perception
• WeberFechner law

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Perception Delusionss
Which of these circles is bigger?
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Perception Delusionss

• Effect of Contrast

Lighter
Darker
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Perception Delusionss
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Is anything here?
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Gestalt Laws

• Proximity
• We tend to group nearby objects.
• Similarity
• We tend to group objects with similar properties
• Closure
• We are so accustomed to seeing closure that we
  sometimes close things that aren't.

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Gestalt Laws

• Good Continuation
• We tend to assign objects to an entity that is
  defined by smooth lines or curves
• Pregnantz
• We tend to good shape

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Experiment 2
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Multistable perception

• Mind separate figure and backgroun.
• Unstably between two or more alternative
  interpretations.
• Since you see both, you cant see both.
• Changing may be under control only partially.

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Invariance in perception

• Objects are recognized independent of rotation,
  translation, scale, elastic deformations,
  different lighting, and different component
  features.

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Neisser's cycle of perceptionCognitive Ecology
Actual world
Object available information
Samples
Modify
Schema of environment
Exploration
Locomotion and action
Cognitive map
Directs
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Psychophysics

• Ernest Heinrich Weber  (17951878)
• Gustav Theodor Fechner (18011887)
• Stimulus ? Percept
• Stimulus ? Sensation ? Percept

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Weber law

• Ernest Heinrich Weber  (17951878)
• Experiment with weight difference
• Just noticeable difference (jnd) between two
  weights was approximately proportional to the
  mass of the weights
• ?I kw I
• I Base intensity (Total weight)
• ?I Discrimination threshold (Weight difference)
• kw Constatnt (Weber Fraction)
• We cant perceive the intensity of stimulus
  directly, but in relation to the reference value.

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Fechner law

• Gustav Theodor Fechner (18011887)
• Dependence of sense impression on the intensity
  of stimulus is logarithm.
• P k ln (S)
• P percept
• k constant
• S stimulus

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Experiment 1

• Dependence of sense impression on the intensity
  of stimulus

• Sound
• Light
• Procedure
• Set intensity to basic level (L)
• Increase intensity up to one degree (L1)
• Remember this degree and set intensity up to L2,
  L3, Ln

Impresion
Sensum
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Fechner law
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WeberFechner Law

• ?P k (?S/S)
• dP k dS/S,
• P k ln (S/S0)
• P percept
• k constant
• S stimulus
• S0 lower possible stimulus

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Weber-Fechner law

• Weber-Fechner principle in the acoustics
• LI10 log (I/I0)
• Lp20 log (pe/pe0)
• L Level of intensity
• I Intensity
• P Aacoustic pressure
• I0, pe0 ... Minimal perceived value