An introduction to Cognitive Sciences
session 2
Pierre De Loor deloor@enib.fr
www.enib.fr/~deloor
Models and simulation
Theorie Hypothesis Observable
Experimentation validation
Model
Simulation
Prediction
validation
Example
• 2 hypothesis to « reach » a target
h1 - We evaluate the final position of the target and we go toward this point
h2 – We move constantly to preserve the object in front of us
Model – h1
Model – h2
« subjective » Evaluation
Group 1 Is this behavior realist ?
Model – h1 Model – h2
Group 2 Is this behavior realist ?
no yes
no yes
« Objective » evaluation
Real data 1 : Real data 2 Real data 3 Real data n
Model – h2
Model – h1 in out
in out in out in out
out out out
out out out out
out
Similarity
analysis 0.9
Similarity
analysis 0.1
Insoluble conflict ?
Objective Pros :
Cons :
Subjective Pros :
Cons :
Example for problem solving
[Danis, Santolini, Tijus 2000]
• Observation of 180
childrens (2-3 years old)
• Hypothesis (for 2-3 years childrens) :
– Hierarchie of properties :
– Color
– Place
– Shape
Example of problem solving simulation [Danis, Santolini, Tijus 2000]
• Rule based model : 5 rules to select a slot
– R1 : The free slot with the same color
– R2 : Else : one free slot from the left to the right
– R3 : slot with the same color than slot occupied by pieces of the same color
– R4 : slot occupied by a piece of the same color (from the left to the right if they are numerous)
– R5 : slot on by one
• The simulation predict a majority of error/success of a lot of childrens.
• Some chidren exhibit differences (for example from the right
to the left rather than from the left to the right).
Simulation is also used for neuroscience
http://bluebrain.epfl.ch/
https://www.humanbrainproject.eu
L’Exaflops pour 2020
Reconstruction and Simulation of Neocortical Microcircuitry
• Article de 82 Auteurs, Cell, Volume 163, Issue 2, 8 October 2015, Pages 456–492
Volume 163, Issue 2, 8 October 2015, Pages 456–492
0.29 mm3
~31000 neurons 55 layer-specific morphological 207
morphoelectrical neuron subtypes
~8 million connections
~37 million synapses
Simulation
reproduce different in vitro and in vivo experiments
without parameter
tuning
A : Tremendous work
Neuro simulation
• Pros
– Understanding disease (Parkinson, Alzeimer ...) – Evaluation of hypothesis (in silico as model)
– Pedagogical material (prevention)
• Cons
– Is this level of detail sufficient, useless to explain cognition ?
– Where is the link with eduction, environment,
body and culture ?
Caricatural Cognitive approach
processing
symbol reasoning
Memory or knowledge
symbol processing
acting
• Mind is information processing : metaphor of computer
• The goal of the researcher is to explain and to detail each functions
• Some debates and some observations take
into question this view
Caricature of the Cognitive approach in neurosciences
• Brain area = cognitive functions
But recent advances : « connectom »
[Liza Grooss 2008]
Studies on perception
• Cognitivism assumes the separation of the studie of each box
processing
symbol
reasoning
Memory or knowledge
symbol
processing
acting
But some evidences shows that it
is not so separable ...
Studies on perception
• automatic processing, unconscious
presupposition, links with memory and habit
• Example : the light come from the top
Unconscious presupposition
• The world is in 3D : Müller-Lyer Illusion
Attention during perception
• We can’t « understand » two talks in the same
time [Mackay 1973].
A example of problem : Unconscious rescontruction
Close the right eye and fixe the circle with your eye in the center
We don’t see that we don’t see !!
Another problem : Attention during perception : example
• How many passes does the team in white make ?
• video
What is perception ???
- Attention, Polymodality, Cross-modality :
- Cats only perceive birds if they hear them and see them (Stein & Meredith, 1993)
- McGurk effect (ba voice – ga lips = da) - Double-flash illusion
- Rubber hand illusion
Illusory Flashing
• Hearing 2 beeps while one flash : perceiving 2 flashes
• 1 beep don’t disturb the perception of the
number of flashes
no sounds
1 beep
