A Functional Framework for Cognition

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A Functional Framework for Cognition
Cognitive Neuroscience and Embodied Intelligence
Based on book Cognition, Brain and Consciousness
ed. Bernard J. Baars
Janusz A. Starzyk
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• It seems that the human mind has first to
  construct forms independently before we can find
  them in things Knowledge cannot spring from
  experience alone, but only from a comparison of
  the inventions of the intellect with observed
  fact.
• Albert Einstein (1949)

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Functional Framework

• The functional framework used combines two
  classical models of cognition
• Baddeley Hitch, 1974
• Atkinson Shiffrin, 1968
• Yellow arrows symbolize voluntary (top-down) and
  spontaneous (bottom-up) attention.
• Long-term memories, knowledge and skills are
  shown in grey boxes at the bottom
• Recent version of Baddeleys Working Memory
  (2002) is in the center

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Habits Motor skills
Declarative knowledge
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Major Functions of Human Brain
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Working Memory
Working Memory
Sensory buffers
Bottom up attentional capture
Central Executive
Top-down Voluntary Attention
Action planning
Vision
Response output
Hearing
Working Storage
Touch
Verbal Rehearsal
Visuospatial Sketchpad
Learning retrieval
Stored memories, knowledge skills
Perceptual Memory
Visual knowledge
Habits Motor skills
Autobiographical Memory
Declarative knowledge
Linguistic Semantic
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Working Memory

• The middle column of boxes are components of the
  working memory.
• The central executive is believed to be part of
  the prefrontal lobes and has a role similar to
  executive of a large company.
• Deals with learning tasks,
• Supervisory control over all voluntary activities
• Working storage involves the medial temporal
  cortex and prefrontal regions.
• Is dynamic, hence more vulnerable to disruption.

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Working Memory

• The executive part of Working Memory involves the
  prefrontal lobe.
• The verbal part --- such as rehearsing words or
  numbers silently --- involves the speech areas of
  the cortex (especially the dominant hemisphere).
  E.g., Broca and Wernicke's areas.
• The visual part --- such as visual imagery to
  think about how to walk from one place to another
  --- seems to involve visual regions.

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Working Memory

• Inner senses, verbal rehearsal and visuospatial
  sketchpad, interact constantly with the long-term
  stores.
• Verbal rehearsal/inner speech is for rehearsing
  and memorizing information and commentary on our
  current concerns, while vocal tract is inhibited.
• Tied to linguistic and semantic component
• Ability to temporarily hold visual and spatial
  information is referred to as Visuospatial
  sketchpad.
• Also involves abstract and cross-modal (more than
  one sense) spatial information
• Sensory systems begin as domain specific, but are
  interpreted as part of multimodal space.

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Working Memory

• Long term stores are for knowledge and practiced
  expertise.
• Not conscious once stored, but interact
  constantly with active functions.
• Parts of system work with others, but can also
  compete against some.
• The output components are under frontal control
  and are related to voluntary motor functions,
  control of skeletal muscles and some mental
  functions.

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Working Memory
Hippocampus plays an important role in forming
new episodic memories

• Damage to the brain, medial temporal lobe (MTL)
  can result in inability to move information
• Cognitive functions are spared, but
• Ability to encode and retrieve new experiences
  are lost.
• Immediate memory is needed to perform all tasks.

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Working Memory

• In case of the damage to MTL there is no link
  from working memory to stored memories.
• Subsequently these new episodes cannot be
  recalled.

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Immediate Memory

• Immediate memory is needed even for simple
  activities like
• Reading.
• Face recognition.
• Eating food.
• Tying shoes.

• It involves sensory-motor coordination to do
  cognitive tasks.

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Limited and Large Memory Capacity

• Brain is large, but its memory capacity is
  limited.
• Brain has billions of neurons and involves
  complex sensory and motor processes.
• Large long-term memory (LTM).
• Short-term memory (STM) is limited to 7/-2.
• Efficiency increased by chunking, i.e., condense
  information.
• Low efficiency during multitasking, difficult to
  do even 2 conscious tasks.
• Practice can improve efficiency.
• Limited functions are associated with conscious
  experience and large capacity functions are
  generally unconscious.

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Limited and Large Memory Capacity

• Dual Task limits
• In dual tasks test, as cognitive demands of one
  goes up, the efficiency of the other one goes
  down.
• Novel problems require much effort, brain makes
  errors and tend to do them sequentially.
• When skills refine they may be performed with
  less conscious effort.
• Some memories are very large.
• Episodic and biographical memories are estimated
  at 1 bln bits (Landauer, 1986).
• Semantic and procedural memories are also very
  large.
• Large language vocabulary with related ideas,
  sounds and written words.

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Measuring Working Memory

• Working memory is tested by presenting a number
  of visual stimuli for recall
• Test may involve recalling a one shown before,
  two slides ago, three slides ago etc..
• The longer the delay the more difficult the
  recall.
• Measured is the recall accuracy and speed.
• Brain activity increases with difficult tasks

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The minds eye, ear and voice

• In 4th century BC Aristotle suggested that visual
  images were faint copies of the visual
  sensations
• Recent research confirms the he was right.
• C.W. Perky (1910) showed that people confuse
  faint visual pictures with their own mental
  images.
• Ganis (2004) write that visual imagery and
  visual perception use the same neural machinery.

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The minds eye, ear and voice

• Imagery tasks
• Classic rotation stimuli
• check whether two arbitrary shapes are the same
  or different
• To answer the question subject mentally rotates
  one shape to match the other
• Classic tower task
• Roll color ball from one pocket to another one
• How to transform the upper picture to the lower
  one
• Subjects use visual imagery but the task is
  different.

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The minds eye, ear and voice

• Most people talk to themselves
• Ask a person to tell about his private monologue
• Or write down an internal speech as it occurs
• Dell and Sullivan (2004) showed that internal
  tongue-twisters create very similar errors to
  regular ones
• Try repeating Peter piper picked a peck of
  pickled peppers in internal speech as quickly as
  possible
• Did you noticed inner pronunciation errors in
  spite of not really using your tongue?
• Inner talk is confirmed by functional brain
  imaging

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Sensory Functions
A functional framework.
Sensory Input
Sensory buffers
Bottom up attentional capture
Central Executive
Top-down Voluntary Attention
Action planning
Vision
Response output
Hearing
Working Storage
Touch
Verbal Rehearsal
Visuospatial Sketchpad
Learning retrieval
Stored memories, knowledge skills
Perceptual Memory
Visual knowledge
Habits Motor skills
Autobiographical Memory
Declarative knowledge
Linguistic Semantic
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Sensory functions and sensory memory tend to be
in the posterior half of cortex.
Left lateral view
(Left hemisphere)
SENSORY Functions
Medial view
(Right hemisphere)
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Motor and executive functions.
A functional framework.
Sensory Input
Sensory buffers
Bottom up attentional capture
Central Executive
Top-down Voluntary Attention
Action planning
Vision
Response output
Hearing
Working Storage
Touch
Verbal Rehearsal
Visuospatial Sketchpad
Learning retrieval
Stored memories, knowledge skills
Perceptual Memory
Visual knowledge
Habits Motor skills
Autobiographical Memory
Declarative knowledge
Linguistic Semantic
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Motor functions and planning are frontal.
Left lateral view
(Left hemisphere)
Medial view
MOTOR Functions
(Right hemisphere)
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Central Executive

• The prefrontal lobes play an important executive
  role in the brain.
• They are needed for voluntary control over
  actions.
• Prefrontal also support emotional processes and
  are necessary to control ones unwanted impulses.
• Stroop Color-naming task is used to test for
  frontal lobe damage.
• Conflict between reading a word and
  and naming its color.
• Highly practiced actions (reading) tend to be
  automatic, while novel and unpredictable ones
  tend to remain under voluntary control.
• Automatic and voluntary control work
  hand in hand

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Selective attention and conscious (reportable)
events.
A functional framework.
Sensory Input
Sensory buffers
Bottom up attentional capture
Central Executive
Top-down Voluntary Attention
Action planning
Vision
Response output
Hearing
Conscious event
Working Storage
Touch
Verbal Rehearsal
Visuospatial Sketchpad
Learning retrieval
Stored memories, knowledge skills
Perceptual Memory
Visual knowledge
Habits Motor skills
Autobiographical Memory
Declarative knowledge
Linguistic Semantic
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Selective Attention and Conscious (reportable)
Events

• Attention improves our ability to perceive
  stimuli.
• In the case of executive attention, the executive
  regions of the prefrontal lobe shapes perceptual
  activity in the posterior half of cortex.
• Conscious events seem to mobilize frontal and
  parietal regions of cortex.
• Voluntary actions become automatic with practice
  and they do not need executive control.
• Brain uses combination of voluntary and
  spontaneous control

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Executive (Voluntary) and Spontaneous Attention

• Spontaneous attention to find a target on the
  left.
• Voluntary attention to find a target on the right

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Voluntary Action Control

• Motor hierarchy begins with general goals
• The goals are represented in the prefrontal area
  and proceed to supplementary and pre-motor
  regions which triggers intention to act
• The primary cortical motor region (M1) triggers
  movements of skeletal muscles.

The brain regions activated in pushing a button
with the right hand
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A functional framework.
Sensory Input
Sensory buffers
Bottom up attentional capture
Central Executive
Top-down Voluntary Attention
Action planning
Vision
Response output
Hearing
Working Storage
Touch
Verbal Rehearsal
Visuospatial Sketchpad
Long term Memories
Learning retrieval
Stored memories, knowledge skills
Perceptual Memory
Visual knowledge
Habits Motor skills
Autobiographical Memory
Declarative knowledge
Linguistic Semantic
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Consolidation of Events into LTM
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Long-term Memories
Long-term memory functions are widely distributed
throughout the brain by means of long lasting
connections. Posterior half of cortex involves
perceptual regions, while executive and motor
memory, such as plans for future actions, engage
frontal regions. Hippocampus is involved
episodic memory, while subcortical basal ganglia
and cerebellum are responsible for motor learning.
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Summary

• We discussed broad concepts for cognitive
  neuroscience.
• Working memory is a foundation of learning and
  cognition.
• Immediate memory seems to depend on medial
  temporal lobe including two hippocampi.
• Damage to this regions impairs formulation of
  long term memories.
• The rear half of cortex is involved in sensory
  processing and in sensory-perceptual memory.
• The from half of cortex is involved with motor
  and executive functions and long term memory for
  these processes.