HOORCOLLEGES COORDINATION DYNAMICS
HOORCOLLEGE 1
small interaction in a group → big coordination patterns (in a big group, like a
group of fish)
neural population, soccers teams, no one is incharge but these patterns emerge in big
patterns
coordination dynamics: set of ideas that describes, explains and predicts how patterns of
coordination form, persist and change things. can be influenced
- task constraints (speed)
- organismic constraints (experts, patho)
- time (learning, ageing, training)
Incorporates both self-organization and more directed forms of coordination (intention,
instructions, explicit environmental coupling)
directed organized coordination = organized manner
- commander tells you what to do
self organized coordination = non organized manner
→ with clapping the self organized coordination is strong coupling (clap and
sound)
- no leader → but you can adjust your movement obv what the others are
doing
- rhythmic can arise in a self organized pattern
top down vs bottom up organization (coordination arise because of an interaction between
the components in the system)
change → pattern switches
you see this in an applause → the applause is long and in the beginning it is fast
(randomized) and after a time the whole concert hall is clapping in synchrony
and after that it will be again random
slide:
1. high sounds because there is no synchronized clapping
2. starts oscillation → more periods → synchronized applause → all hands
together and all not together = periods of silence = overall noise level is
less
conflict: desire make as much noise as possible vs do what your neighbours are doing
Demystifies the popular term “emergence” by demonstrating how the interactions among the
parts can produce coordinated behavior
why can’t we have both
- we cannot clap in synchronized in a very fast tempo/ high sound
artikel Neda et al. 2000
➢ synchronized but quieter = red
○ you clap slow
, ○ less claps per second
○ freq is small domain
➢ loud but unsynchronized = black
○ frequency increases for the clapping
○ the spread of the frequency is a lot wider than the not enthusiastic
○ there is a large variance between persons and within persons, the spread is
wide because the the clapping frequency is for everyone different
○ it is difficult because the components are too different. The freq domain is too
big.
○ this is a conflict of making much noise vs do it in synchrony
empirical intuitive approach: being able to interpret model figures, indicate stable patterns
etc, you have to interpret it.
sports: defender vs spits, they have different goals. but in rowing the group has the same
goal. competitive and cooperative interpersonal coordination
synergetics
- is a rigorous, operationally defined approach that focuses on spontaneous pattern
formation
- is nomothetic approach (i.e., single law for many different systems) = strength of the
approach, we focus on small systems like 2 hands
- exploits formal analogies (i.e., empirical equivalents)
rayleigh benard convection
fluid: complex system consisting of many interacting subsystems
➢ open system: change of info through the system
➢ temp gradient in the fluid (warmer below) → known as control parameter,
we can tune the parameter and is unspecific (it doesn’t tell the molecules
of the fluid what to do) → leads to qualitative change in behavior (rest to
motion). previous state disappear and can change to two states (fluid can
go to each direction)
➢ Simulation of formation of convection rolls with large temperature gradient R
➢ cold fluid go down and heat go up, which pattern emerge is because of chance
○ that a specific pattern emerge based on critical value of control parameter =
certainty
Pitchfork bifurcation diagram: a qualitative change in the order parameter q with R
x as = control parameter = temp gradient
y as = order parameter = low dimensional characterization of
the system = rotation frequency / amplitude
- is 0 when the temp is low, no convection rolls = at rest
- red is the previous rest state of the system
- when the temp gradient increases above the critical
value of rest, the system will not be in a rest state
anymore. it trunks, it goes upwards because of local
interaction (bottom up) or downwards (top down). you
can only take one way, but it depends on chance. it looks like a pitchfork (for piano).
, - there is a change in state from one mono stable ( freq is zero for the order
parameter, for R the control parameter) = qualitative change or a phase transition
the order parameter indicates the state of the system (clap in synchrony or not)
circular causality
Order parameter emerges from interactions among the parts, but the order parameter in turn
simultaneously enslaves the behavior of the parts
interaction leads to the formation of particular order (like clapping in synchrony), we can
investigate macroscopony
it is very difficult for a molecule or person who is clapping to escape from that synchronized
system (like clapping) = circular causality. if the situation is there from the interacting
subsystems, as soon as it is formed it is difficult for these subsystems to do something else
if you clap with each other and we have to clap faster and faster than we go from
synchronized clapping to non synchronized clapping. The frequency itself does not for
anyone describe you if you have to escape from that synchrony or not (it is unspecific to
the behavior of the whole), same for the temp gradient. it does not tell the molecules what to
do.
the order parameters emerge because of interactions of the subparts (bottom, up). but the
control parameters simultaneously enslave the subparts (top down), it is difficult to do
something else.
circular causality: movements of persons set the millenium bridge in motion. but the motion
of the millennium bridge makes it difficult for the persons to do something else of what is
dictated by the motion of the bridge.
the macroscopic behavior of the whole can be modelled by potential functions, stable states
are indicated
ball in landscape with gravity, it will slide down to the lowest point = attractor
low values of the control parameter = there is only one valley. always contracted to that
specific valley (monostable)
the steeper the walls the stronger it will be attracted to that specific state
on the right side, the convections rolls could be in 2 different ways (bistable), there are two
valleys. it depends on the original position where the ball will end.
on the hilltop a small noise will move the ball to the right or to the left. it depends on change
it represents the state of the system in potential functions/ landscapes
, x-as is here the order parameter, y as potential
test example: he can ask to draw the potential landscapes by the pitchfork diagram
slide 27: arrow indicates the instability
stable when control parameter is at zero (fluid is at rest) = open dot
a really flat surface (not a valley), a small perturbation will change the state, but it will not be
attracted to a specific state and it will not return to the state because it is really flat.
(part 3 lecture 1)
Kelso: phase transition story → let your fingers do the walking
quadruped finger walking transitions
one coordination patterns is more easy, more stable than another
- alternate index and middle finger within in a hand
- synchronizing index and fingers between hands
- used a metronome to speed up
difficult: pattern from left hand index finger was forward and on the right hand
the middle finger was forward (AP)→ synchronized both hand middle/index
fingers between the hands. plus how faster the frequency the more it was
difficult. at slow speed both patterns could be performed whereas at fast
frequency only the synchronized pattern.
slide 32: 2 components: index fingers both hands
rhythmic finger task:
➢ inphase vs antiphase (synchronized flexion/extension vs afwisselend)
➢ “Produce one full cycle for each metronome beat. If the pattern does change, don’t
try to go back to the original pattern but stay in the one that is most comfortable.
Above all, try to keep an one-to-one relationship between your rhythmical motions
and the metronome beat”
➢ 1-1 relation between rhythmic motion and the metronome (control parameter). the
faster you go that maybe is a drive to go from one pattern to the other.
➢ inphase/ synchrony: the faster. no pattern switch and no instability.
➢ antiphase: the faster the more difficult. the pattern changed to the inphase pattern.
○ around the end the flexion and extension of both fingers at the same time
○ seperation of time skills of what the components are doing (fast components
dynamics) move very fast compare to the level of the order parameter
(relative phase between the fingers = slow)
■ it goes from 180 graden to 0 (from antiphase to inphase)
■ change is very slow = slow order parameter dynamics, relation
between the fingers , relative phase between the two fingers. also
called: collective variable
pitchfork bifurcation soup: transition from a monostable to a bistable state/ rotation in
one direction or the other (where the previous stable states becomes unstable)
in the finger experiment it is a reverse pitch bifurcation diagram
transition from a bistable regime to a monostable regime
➢ order parameter is the relative phase between the fingers (0 degrees inphase and
18- degrees antiphase)
