Science - USA (2021-11-12)

content words but featuring three different
syntactic structures: a coordinated clause (e.g.,
“The writer admires the poet and writes the
paper”), a subject-relative clause (e.g.,“The

writer that admires the poet writes the paper”),

or an object-relative clause (e.g.,“The writer

that the poet admires writes the paper”; Table

1A). Each sentence was followed by a test af-

firmation (e.g.,“The poet admires the writer”;

Table 1B), which the participants had to judge

as true or false with respect to the immediately

preceding sentence. The participants succeeded

Thibaultet al.,Science 374 , eabe0874 (2021) 12 November 2021 2 of 14

A B

C

D E

F

GHI

Fig. 1. Experiment 1: Overlap of syntax and tool-use planning activity.(A) Setup
and experimental design of the syntactic task. (B)d′(left graph) and RTs (right
graph) for the syntactic comprehension of the three sentence structures. Both the
one-way rmANOVA ond′and the LMM on RTs showed a significant main effect of
Sentence(d′:F(1.6,30.6)= 40.04;P< 0.001;ƞG^2 = 0.49; RTs:c^2 (2)= 25.21,P< 0.001).
Error bars show SEs. ***P< 0.001, Tukey’s post hoc test. (C) Statistical maps
thresholded atP< 0.001, uncorrected, for syntax (object relatives compared with the

two other sentence types). (D) Setup and experimental design of tool-use and free-

hand motor tasks. (E) Statistical maps thresholded atP< 0.001, uncorrected,

for tool-use planning. (F) Joint neuronal activity for syntax and tool-use planning in

the BG, thresholded atP< 0.001, uncorrected. (GtoI) Average brain activity

level in each cluster significantly activated by both tasks. The highest activations

were found for tool-use planning (blue) and object-relative clauses (yellow) in

the motor and syntactic tasks, respectively.

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