Re-Thinking NeuroConstructivism through Dynamic (neuro)-Enskilment

Mirko Farina

Department of Cognitive Science

mirko.farina@mq.edu.au

Cognitive Science Workshop, December 5th 2012

A larger project …

• Nativism/ Modularity / Neuroconstructivism / Enculturation

• Goal: attack weak forms of nativism (typically Marcus’ neo nativism) by suggesting a revision/radicalization of the framework proposed by standard neuroconstructivism

• In this short talk, however, I am going to be presenting only the material on standard neuroconstructivism and will just hint at how it bears on the nativism debate in a concluding slide at the very end of this talk

Today’s Talk

In this paper I discuss two views - standard

neuroconstructivism, and dynamic neuro-enskilment

- that explain human cognitive and cortical

development from slightly different standpoints

I compare these views and critically analyse the

links between them

The Main Goal of this Talk!

I do so to demonstrate that what I call ‘standard neuroconstructivism’, in order to fully account for recent empirical findings, needs to be updated and radicalized along the lines envisaged by the dynamic neuro-enskilment view

Standard Neuroconstructivism (Karmiloff-Smith, Mareschal, Johnson, Westermann,

Elman, Thomas ...)

Framework for the study of cognition that draws on, and integrates, different views of brain and cognitive development such as:

(1) ‘probabilistic epigenesis which emphasizes the interactions between experience and gene expression (Gottlieb 2007)

(2) neural constructivism which focuses on the experience-dependent elaboration of neural networks in the brain (Purves 1994; Quartz & Sejnowski 1997)

(3) the interactive specialization view of brain development which focuses on the mutually constraining interactions of different brain regions in shaping the developing brain (Johnson 2001)

(4) embodiment views that emphasize the importance of the body in cognitive development and processing (Clark 1999; Smith 2005)

(5) Piaget’s constructivist approach to development that stresses the pro-active acquisition of knowledge by the child, and

(6) approaches highlighting the role of the evolving social environment for the developing child’ (Westermann, Thomas, and Karmiloff-Smith 2010, p.724).

The impact of standard neuroconstructivism in philosophy

Few Naggings …

• Much of the philosophical enthusiasm for the developmentally based work of Elman 1993, Karmiloff-Smith 1992, which culminated in the collaboration between Clark and Karmiloff-Smith (1993a,b), and more famously in the publication of Rethinking Innateness (Elman et al. 1996), hasn’t been carried through to present days and neuroconstructivism, after receiving a lot of press from philosophers in the early ‘90s, has totally dropped off the philosophical radar since

• The Philosophers' Index database lists only three papers on neuroconstructivism in the 2000s... I find this rather odd!

• In this paper, by returning (as a philosopher) to neuroconstructivism , I attempt to make it the centre of a fresh and new “theoretical” debate

The Dynamic Neuro-Enskilment View

• The dynamic neuro-enskilment view retains a standard neuro-constructivist basis *BUT* integrates within it ideas about distributed enculturated

cognition/cognitive ecologies (Roepstorff and Niewoehner [2010], Hutchins [2010]) and new work on neural plasticity in neuropsychology [Giedd 2009] and

cultural neuroscience (Chiao [2009], Kitayama and Park [2010])

• Theorizes a profound dependence of brain organization and cortical development on both patterned practices and cultural/social activities

• Emphasizes the power of brain plasticity, expertise, and rewiring throughout the entire lifespan. Crucial Tenet: adult entrenchment in different socio-cultural

contexts can generate completely dissimilar neural responses, leading to structurally different, cognitively diverse, and deeply enculturated brains.

Standard neuroconstructivism is the theory that characterizes development as a trajectory that is shaped

by multiple interacting biological and environmental constraints, in which complex representations develop

based on earlier and simpler ones

This increase in representational complexity

is realized through a progressive elaboration of

functional cortical structures, which are not

selected from a constrained juvenile stock but rather

emerge in an experience-dependent way

Standard neuroconstructivism argues for progressive elaboration of neural structures with earlier structures forming the building blocks for

later structures and describes development within a perspective of context-dependent learning

Thus, standard neuroconstructivism calls for

consistency between the neural and cognitive levels in

characterizing developmental trajectories, posits the

interrelatedness (on multiple timescales) of brain, body, and

world, and argues that the interweaving of all these factors

is crucial for cognitive development

How the Brain constructs Cognition …

‘Human intelligence is not a state (i.e., not a collection of static, built-in

modules that can be intact or impaired) but a process (i.e., the

emergent property over developmental time of dynamic,

multidirectional interactions between genes, brain, cognition, behavior, and

environment) with domain-specific outcomes impossible without the

process of development’ (Karmiloff-Smith 2009)

The brain is fundamental for cognitive development – *BUT* no reductionist standpoint – cognitive change not just

neural adaptation

Rather cortical specialization is the result of a process in which

constrained mental representations get reshaped via learning and experience

dependent activities

Thus, standard neuroconstructivists describe brain fine-tuning, its regional

specialization, and gradual development as constrained by

environmental exposure in the world

Standard Neuroconstructivism and Learning ...

Learning is a constructive process that is realized by

means of continuous changes operated on constrained cortical

structures that are moulded in early stages of infancy by

experience dependent activities

Standard Neuroconstructivism and the Sensitive Window ….

There is a sensitive period for learning for them then, in the sense that it is only if the early

structures are in place that we can get the later structures since these build on what has

occurred in early stages of life

This doesn’t imply that the brain can’t continue to change itself through learning

at later stages but just that the ways in which it can change itself are severely constrained by experience-dependent

activities undergone in infancy

Spot on! (with two concerns…)

1) Is cognitive development severely

constrained by experiences undertaken in early childhood? Unique

Sensitive Window?

2) What is the role that expertise and experience-based neuronal plasticity

play in redirecting the developmental path in

adulthood?

Giedd and colleagues (2006, 2009) demonstrated the existence

of a second period of synaptic plasticity in adolescence

This second wave of synaptic over-production (in all respects analogous to the one that takes place in early

childhood) constitutes a second window of opportunity for the

developing adolescence

‘What is most surprising is that you get a second wave of overproduction of gray matter, something that was

thought to happen only in the first 18 months of life’

1. Rewiring Constraints...

Show that the belief that the brain has fully matured by the age of 8 or 12, with the truly crucial wiring complete as early as 3, is false. The brain is an ongoing construction site

where development does not stop at age 3 or 10, but continues into the teen years and even the 20s

‘The brain undergoes dynamic changes much later than we originally thought.

Maturity is not simply a matter of slipping software (learning) into existing

equipment. Instead, the hardware changes. Think of it as nature's way of giving us a second chance’ [see Sowell

(UCLA) and Todd (Harvard/Utah)]

AREAS : corpus callosum– amygdalae – pre frontal cortex –

nucleus accumbens – hippocampus "

These results do not yet offer direct empirical evidence for the dynamic neuro-enskilment view, but question the idea of a unique phase-sensitive window

of opportunity confined to childhood and so emphasize the possibility of completely rewiring

already rewired and constrained cortical structures

Transcultural neuroimaging studies that have

highlighted the intrinsically biosocial nature of the

functional organization of the human brain

2. Evidence for the Dynamic Neuro

Enskilment view ..

London Taxi Drivers (Maguire et al. 2000)

Relative to the hippocampi of matched control subjects [non taxi

drivers and bus drivers], the hippocampi of the cab drivers

showed a substantial enlargement in the posterior part

This structural difference was related to cab driving and was

reported to be proportional with the number of years of experience as a taxi driver

Jugglers (Draganski et al. 2004)

Draganski used MRI to visualize learning-induced plasticity in the brains of trained volunteers who have learned to juggle from scratch for approximately

60 seconds without dropping a ball over a period of three months

Relative to the brain of controlled subjects (non jugglers) the

experimenters found out that there were significant changes involved in the volume of white

matter in the brain of the jugglers

Canadian Mail Sorters (Polk and Farah 1998)

Polk and Farah (1998) designed an experiment to determine whether extensive

socio-cultural activities undertaken in adulthood could have an effect on this

dissociation

They tested Canadian postal workers who spend days sorting mail by postal code

Results were fascinating: compared to fellow postal workers who do not sort mail, Canadian mail sorters, show significantly less behavioural evidence for segregated

letter and digit processing

Jazz Musicians (Vuust et al. 2005 – Vuust and Roepstorff 2008)

Jazz musicians react to rhythmic deviations more significantly and in a

shorter period of time than non-musicians

This happens because jazz musicians are routinely

engaged in musical practices that continually involve these

deviations

Classic Musicians (Ohnishi et al. 2001)

Ohnishi and colleagues (2001) compared the brain activation of expert musicians with that of non-musicians

While listening to the same piece of music (namely Bach’s

Italian Concerto), musicians and non-musicians recruited different areas of their brains

Gutchess and Park 2009 – Cultural

differences in neural function associated

with object processing

Culture and Memory (Gutchess et al. 2006)

Where do these findings leave us?

These results provide strong empirical evidence

for the intimate dependence of human

cognition (even in adulthood) on both socio-

cultural/technological environments and

patterned practices

We learn that the environments in which we live have a huge influence in initiating and orchestrating specific physiological processes as well as in organizing, both

anatomically and functionally, our cognitive architectures

We also learn that although the anatomical structures and the cognitive architectures that characterize our brains progress and

develop through a common developmental path, they continually interact with each

other and with their environments to change each other's functions

What Do We Learn?

These results urge standard neuroconstructivists to stretch

and liberalize the sixth dimension of their framework – …’Approaches highlighting the role of evolving social

environments in the developing child’...

Re-Thinking Standard Neuroconstructivism? (Conclusions)

Substantial Revision of their framework?

(Preliminary Conclusion)

OBJECTION! - The point about the sensitivity window is an empirical point in developmental

neuroscience. But is it philosophically relevant to the standard neuro-constuctivist?

What is there in the theory or in the conclusions that are drawn from the theory

that changes once we extend the sensitivity

window? Doesn’t it just require a tweak to the

theory? 

Modularity theorists (e.g. Marcus) have tried

to appropriate constructivist ideas to account for the role of development. Unique Sensitive Windows =

Maturation of Modules

OK let’s agree conclusions might be the same *BUT* the framework is not. The idea of development in the

two accounts is very different. This difference becomes relevant when we look at a broader picture

So the empirical point we thought was not philosophically relevant to the neuroconstructivists turns out to be philosophically decisive. In other words, it is philosophically relevant to the neuroconstructivist

because it is relevant to the nativists in the first place….

How do nativists account for a second window of

opportunity? ‘Re-Maturation’ of already matured modules?

Sounds like an ad hoc hypothesis….

A Special Thanks to:

• John Sutton• Julian Kiverstein• Richard Menary• Andy Clark• MacNaP Audience

• Macquarie University • You All