Title: A Functional Framework for Cognition
1A Functional Framework for Cognition
Cognitive Neuroscience and Embodied Intelligence
Based on book Cognition, Brain and Consciousness
ed. Bernard J. Baars
Janusz A. Starzyk
2- 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)
3Functional 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
4Habits Motor skills
Declarative knowledge
4
5Major Functions of Human Brain
6Working 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
6
7Working 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.
8Working 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.
9Working 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.
10Working 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.
11Working 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.
12Working 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.
13Immediate 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.
14Limited 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.
15Limited 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.
16Measuring 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
17The 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.
18The 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.
19The 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
20Sensory 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
20
21Sensory functions and sensory memory tend to be
in the posterior half of cortex.
Left lateral view
(Left hemisphere)
SENSORY Functions
Medial view
(Right hemisphere)
21
22Motor 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
22
23Motor functions and planning are frontal.
Left lateral view
(Left hemisphere)
Medial view
MOTOR Functions
(Right hemisphere)
23
24Central 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
24
25Selective 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
25
26Selective 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
27Executive (Voluntary) and Spontaneous Attention
- Spontaneous attention to find a target on the
left. - Voluntary attention to find a target on the right
28Voluntary 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
29 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
29
30Consolidation of Events into LTM
31Long-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.
32Summary
- 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.