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Michael I. Posner and Mary K. Rothbart

University of Oregon, Eugene, USA

Progress in neuroimaging and in sequencing the human genome make it possible to think about neural
rks in terms of experiential and genetic factors that shape their development. In this paper we use
both of these these methods to explore the development of attentional neworks.

Attentional Networks

Three major functions of the attention system are: ach
ieving and maintaining the alert state, orienting to
sensory events and voluntary control of responses (Posner & Fan, in press). While all humans have an
attention system, the efficiency of its operation clearly differs between people.

We have carried ou
t an extensive series of investigations on an attentional network related to self
regulation of cognition and emotion (Bush, Luu & Posner, 2000). We have developed the Attention
Network Test (ANT) to assay the efficiency of this and other attentional netwo
rks (Fan et al 2002). The
ANT relies on the flanker task to provide evidence of conflict and uses cues to induce different states of
orienting and alerting. Imaging studies of adults demonstrate that the three functions are carried out by
separate anatomic
al networks, and imaging also shows that a number of conflict related tasks that can be
run with children have common activations in the anterior cingulate and lateral prefrontal areas.

We also have developed a child ANT, with particular interest in study
ing the executive attention network
, related both to self regulation and the ability to resolve conflict. Using the Child ANT and related tests
we found that the executive attention network develops between age 2 and 7 years, but remains constant
after th
at (Rueda et all, 2004).


Cognitive measures of conflict resolution in these laboratory tasks have also been linked to aspects of
children's temperament. Children better able to resolve conflict received higher parental ratings of
effortful c
ontrol (Gerardi
Caulton, 2000). We regard effortful control as reflecting the efficiency with
which the executive attention network operates in naturalistic settings. In adolescents effortful control and
the ability to resolve conflict are protective facto
rs for the development of antisocial behavior. Thus
laboratory studies of an individual’s ability to resolve conflict provide an important clue to the likely
difficulty of successful socialization, and also make it possible to use questionnaires measuring
control to better understand how different cultures seek to use attentional networks to build control
systems for their children (Rothbart, Ahadi & Hershey, 1994).

Genetic Studies

Individual differences in effortful control and in the ability

to resolve conflict are highly heritable (Fan et
al, 2001) We have used the Attention Network Test and the association of its networks with particular
neuromodulators to discover two dopamine genes related to performance in resolving conflict (Fossella et

al 2002). A neuroimaging experiment compared persons, with different alleles of these conflict related
genes while they performed the ANT (Fan et al 2003). We found that these alleles produced different
degrees of activation within the anterior cingulate
(Fan et al, 2003), which is a major node of the network
involved in the resolution of conflict. Other work has found cholinergic genes are related to the network
controlling orienting to sensory events (Marrocco & Davidson, 1998; Parasuraman, in press). Th
e finding
that specific genes influence individual differences in orienting to sensory information and resolving
conflict suggests that these same genes may be important in building the attentional networks that are
common to all of us. One of the genes we

found related to executive attention has also been implicated in
attention deficit disorder, and when it is knocked out, mice display a deficit in their ability to explore their


Genes influence the networks underlying human brain

function only in conjunction with experience. It is
a good test of our understanding of how experience influences these networks to determine if we can
design effective training of attention. There is evidence that attention training can be effective in r
from brain injury and in assisting those with developmental attention deficits to overcome them. A central
aspect of the executive attention network is the ability to deal with conflict. We used this feature to design
a set of training exercises fo
r children, adapted from efforts to train macaque monkeys who would be sent
into outer space.

We began to test the efficacy of a very brief five days of attention training with groups of normal 4
old children. We found some evidence that this traini
ng produces more adult like performance, although
the highly variable RTs of four year olds made it difficult to interpret the behavioral data. The EEG data
showed that four year olds after attentional training showed the N2 differences between congruent a
incongruent trials found in adults. We also found significant generalization in IQ scores in the trained
group in comparison with an untrained control. Because of the very brief nature of the training we did not
expect to find substantial improvements,
so the outcome is very encouraging for additional research based
upon more substantial training. This is only the start of what we hope will become an effort to see if
attention training at critical times in development can shape and improve brain networks
. This work has
obvious implications for the development of preschool curricula. As the number of children who undergo
our training increases, we can examine aspects of their temperament and genotype to help us understand
who might benefit from attention t


Many neurological and psychiatric disorders have been said to involve pathologies of attention. Without a
real understanding of the neural substrates of attention, this has been a somewhat empty classification.
This situation is

changed with the systematic application of our understanding of attentional networks to
pathological issues.

Only a few pathologies have been studied by methods which allow us to state which of the attention
networks are affected. More commonly one or an
other of the attentional networks has been examined in
isolation. We discuss in this paper applications to Aging and Alzheimer’s Disorder, ADHD, Autism,
Borderline Personality Disorder, Neglect, and Schizophrenia

Overall we emphasize how neuroimaging and
gentics provides new insight into the role of attentional
networks in human behavior. We believe these new methods, and our effort to integrate them, have
importance for all areas of cognitive science and can be used with the many networks now shown to
erlie aspects of human cognition and emotion.


Bush, G., Luu, P. & Posner, M.I. (2000). Cognitive and emotional influences in the anterior cingulate
Trends in Cognitive Science

Fan, J., Flombaum, J.I., McCandliss, B.D., Th
omas, K.M. & Posner, M.I (2002). Cognitive and brain
mechanisms of conflict.

Fan, J., Fossella, J.A., Summer T. & Posner, M.I. (2003). Mapping the genetic variation of executive
attention onto brain activity.
Proceedings of the Nation
al Academy of Sciences, USA

Fan, J., McCandliss, B.D., Sommer, T., Raz, M. & Posner, M.I. (2002). Testing the efficiency and
independence of attentional networks.
Journal of Cognitive Neuroscience

Caulton, G. (2000). S
ensitivity to spatial conflict and the development of self
regulation in
children 24
36 months of age.
Developmental Science

Fan, J., Wu, Y., Fossella, J. & Posner, M.I. (2001). Assessing the heritability of attentional networks.
BioMed Centr
al Neuroscience

Fossella, J., Sommer T., Fan, J., Wu ,Y., Swanson, J.M., Pfaff, D.W. & Posner, M.I. (2002). Assessing
the molecular genetics of attention networks.
BMC Neuroscience

Marrocco, R.T. & Davidson, M.C. (1998). Neurochemistry of att
ention. In R. Parasuraman (Ed.),
Attention Brain
(pp. 35
50). Cambridge, Mass:MIT Press.

Parasuraman, R. (in press) Molecular Genetics of Visuospatial Attention and Working Memory In
Posner, M.I. (ed) Cognitive Neuroscience of Attention New York: Guild
ford Press

Posner, M.I. & Fan, J. (In press). Attention as an organ system. To appear in J. Pomerantz (Ed.),
Neurobiology of Perception and Communication: From Synapse to Society. The IVth De Lange

Cambridge UK:Cambridge University Press.

art, M. K., Ahadi, S. A. & Hershey, K. (1994). Temperament and social behavior in children.
Palmer Quarterly,

Rueda, M.R., Fan, J., McCandliss, B., Halparin, J.D., Gruber, D.B., Pappert, L. & Posner, M.I. (2004).
Development of attentiona
l networks in childhood.