THE MULTIPLICITY OF EMBODIMENT 123plasticity, biosociality, and embodiment can, in principle, rectify the re-
ductionism and determinism associated with the neurosciences. My own
inquiry was animated by the possibility that attention to neurobiology — as
envisioned in an era of plasticity, epigenetics, and biosociality — can open
up, rather than close down, the material and historical specificity of bodies
and lives. I hoped, in other words, to grasp meanings and neurobiological
bodies together in order to make more room for the whole range of actual,
existing body- minds and body- subjects — especially those that are histor-
ically ignored or pathologized by science — to “have a chance” (Haraway
1988, 580). If this is the promise of the biosocial, plastic brain, it is unevenly
realized in the examples I explored here.
The plasticity of the brain presumably releases it from biological deter-
minism and enables experience to make its mark. But the implications of
this, I argue, often are contingent upon the particular ways plasticity is un-
derstood and enacted. The adolescent brain, for example, is not necessarily
less determined than it was before its renewed ability to sprout and prune
was discovered. Plasticity is sometimes treated as more or less intrinsic in
adolescent brain research, such as when the goal is to map differing degrees
of maturation across multiple brain regions at given moments in devel-
opment, rather than to explore the ways experience diversifies brains and
their developmental trajectories. The result is a universal, mildly pathologi-
cal adolescent brain, with an immature prefrontal cortex that is no match
for its amygdala. This brain is being proposed as a biologically determinist
explanation for various social problems involving youth. Those invested in
biosocial plasticity might be tempted to say that this research is simply not
plastic enough, or that it explores the wrong kind of plasticity. The research
program I discussed on the neurobiological impact of poverty, however, ex-
plores extrinsic, experience- dependent plasticity, to questionable effect in
my view. Here the aim is to understand the biological effects of poverty, as
measured by socioeconomic status, on developing brain systems. To recap,
the general hypothesis is that the brain shows distinctive and identifiable
neural patterns in response to the multiple negative experiences (stress, nu-
tritional deprivation, toxins, drugs, and so on) that tend to mark the lives of
children who are poor more than others. In this research program subjects
are differentiated by (bifurcated, gross) measures of class status, as a proxy
measure of their exposure to a range of physiological and other factors cor-