mappings of complex functions like “language processing” have largely been
replaced by explanations of regional brain function in terms of more abstract
computational properties and context-specific interactions with anatomically
distributed networks. This perspective was already present in Lenneberg’s mind,
when he wrote (Lenneberg 1967: 54) that “We cannot expect to find any kind
of new protuberance or morphological innovation which deals exclusively with
a particular behavior. Any modification on the brain is a modification on the
entire brain. Thus species-specific behavior never has a confined, unique, neu-
roanatomic correlate, but always and necessarily must involve reorganization of
processes that affect most of the central nervous system.”
For this emerging research program to bear its fruits, we must be clear about
what language does. In our view, it is much closer to global cognitive roles
usually discussed in the literature on working memory, consciousness, executive
control, attentional processes, and the like. The picture of linguistic cognition
that emerges is one where the appropriate integration and processing of infor-
mation is key. For this, it is necessary to study the recruitment of large neuronal
assemblies, mediated by the thalamus. This neuronal activity, made coherent
thanks to the intrinsic oscillatory potential of thalamic nuclei, arguably provides
the means to link various neuronal populations as a response to particular aspects
of an experience with regard to its significance and to guiding behavior, a way
to organize the world around us and to make sense of it.
Taking the thalamus as a central region of interest has the added benefit of
shedding light on cognitive disorders. We hope to have provided enough refer-
ences in support of the role of the thalamus in the pathobiology of a variety of
cognitive impairments often taken to be human-specific. In this context, let us
stress that the point here is not to argue that the thalamus is a primary causal
mechanism in all these mental diseases. This is not how we wish to interpret
the data reviewed in earlier sections of this paper. Rather, in agreement with
Tsatsanis et al. (2003), we see “great value in investigating the role of the
th alamus in connection with larger neural systems and clinical dimensions”
relevant to understanding breakdowns of mental health. In particular, in line
with a growing literature on this topic, we have suggested that studying the
role of the thalamus in controlling brain rhythms is very promising.
Given the centrality of the thalamus above and beyond language, down to
embryonic development, its involvement in linguistic cognition may explain why
it appears impossible for the core combinatorial aspects of language to completely
go missing (Moro 2008: 179). Far from being the puzzle that Moro makes it
looks to be, it ma y be a natural consequence of how the essence of the human
language faculty is implemented in the brain.
Note
∗ The present work was made possible through a Marie Curie International Rein-
tegration Grant from the European Union (PIRG-GA-2009–256413), research
funds from the Fundació Bosch i Gimpera, the Generalitat de C atalunya (2014-
SGR-200), and the Spanish ministry of economy and competitiveness (FFI2013–
43823-P and FFI2014-61888-EXP).
The central role of the thalamus 245