A. M. PROVERBIO ET AL.
16
hemisphere) free to monitor their own verbal performance
(Gran & Fabbro, 1989).
Clinical cases of polyglot aphasia have also suggested that
the linguistic representation of L1 and L2 in polyglots might
involve separate neurofunctional circuits, and/or be the result of
a dysfunction of a putative switching mechanism between the
languages. This assumption is based on evidence that, after
insult, polyglot patients may selectively recover one language,
while showing severe aphasic symptoms for the other language
(Abutalebi et al., 2000; Aglioti, 1996; Aglioti & Fabbro, 1993;
Paradis, 1989). In general, although the role of the right hemi-
sphere in bilinguals’ language processing remains controversial,
there is a great deal of evidence supporting a differential intra-
hemispheric representation for monolingual and bilingual
speakers. For example, Dehaene and colleagues (Dehaene et al.,
1997) used fMRI to assess intersubject variability in the cortical
representation of language comprehension in moderately fluent
French / English bilinguals while they listened to stories in the
two languages. They found that while the first language (L1)
activated a similar set of areas in the left temporal lobe in all
subjects, the second language (L2) activated a highly variable
network of the left and right temporal and frontal areas, with
individual subjects varying from a standard left lateralization to
a complete right hemispheric lateralization.
In summary, although further research is certainly needed to
reach a definitive conclusion, it seems that linguistic functions
are less lateralized in polyglots relative to monolinguals. The
difference in lateralization in our study may be because of the
interpreters’ prolonged practice of simultaneous interpreting
strategies. The difference may also be because multiple lan-
guages tend to be differentially represented in the brain, with a
more extended right lateralization of linguistic functions in
polyglots.
Considering that the orthographic task we used in the present
experiments requires basic or simple linguistic processes, such
as recognition of orthographic appearance and letter identifica-
tion, and does not involve the sophisticated professional abilities
of simultaneous interpreters, the data favour the hypothesis that
the reduced left lateralization of linguistic functions in simulta-
neous interpreters may be attributed to the fact that they are
polyglots, and not to the simultaneous interpretation task per se.
The possible limitations of this study refer to the presence of
only female subjects in the interpreter group. It has been indeed
demonstrated a lesser degree of lateralization for linguistic
functions in the female than male brain. This effect might also
possibly explain the prevalence of females in the simultaneous
interpreter population, however further investigation is needed
to reach a definitive conclusion on this matter.
In conclusion, the present data provide evidence of a lack of
right hand preference for right-handed interpreters during an
orthographic detection task. This finding might possibly reflect,
for polyglots, a reduced hemispheric asymmetry for linguistic
functions, normally lateralized to the left hemisphere, as clearly
shown by the strong right lateral preference exhibited by the
monolingual control group.
Acknowledgements
We are grateful to Giuliana Cosma Leoni and Alberto Zani
for their kind support. Funded by MIUR grants.
References
Abutalebi, J., Miozzo, A., & Cappa, S. F. (2000). Do subcortical struc-
tures control language selection in bilinguals Evidence from
pathological language mixing. Neurocase, 6, 101-106.
Aglioti, S., Beltramello, A., Girardi, F., & Fabbro, F. (1996). Neurol-
inguistic and follow-up study of an unusual pattern of recovery from
bilingual subcortical aphasia. Brain, 119, 1551-1564.
doi:10.1093/brain/119.5.1551
Aglioti, S., & Fabbro, F. (1993). Paradoxical selective recovery in a
bilingual aphasic following subcortical lesions. Neuroreport, 4,
1359-1362. doi:10.1097/00001756-199309150-00019
Chernigovskaya, T. V., Balonov, L. J., & Deglin, V. L. (1983). Bilin-
gualism and brain functional asymmetry. Brain and Language, 20,
195-216. doi:10.1016/0093-934X(83)90042-1
Cohen, L., & Dehaene, S. (2004). Specialization within the ventral
stream: The case for the visual word form area. NeuroImage, 22,
466-476. doi:10.1016/j.neuroimage.2003.12.049
Cohen, L., Lehericy, S., Chochon, F., Lemer, C., Rivaud, S., & Dehaene,
S. (2002). Language-specific tuning of visual cortex. Functional
properties of the Visual Word Form Area, 125, 1054-1069.
doi:10.1097/00001756-199712010-00030
Dehaene, S., Dupoux, E., Mehler, J., Cohen, L., Paulesu, E., Perani, D.,
et al. (1997). Anatomical variability in the cortical representation of
first and second language. NeuroReport, 8, 3809-3815.
doi:10.1097/00001756-199712010-00030
Fabbro, F., Gran, B., & Gran, L. (1991). Hemispheric specialization for
semantic and syntactic components of language in simultaneous in-
terpreters. Brain and Language, 41, 1-42.
doi:10.1016/0093-934X(91)90108-D
Fabbro, F., Gran, L., Basso, G., & Bava, A. (1990). Cerebral lateraliza-
tion in simultaneous interpretation. Brain and Language, 39, 69-89.
doi:10.1016/0093-934X(90)90005-2
Flowers, D. L., Jones, K., Noble, K., VanMeter, J., Zeffiro, T. A.,
Wood, F. B., et al. (2004). Attention to single letters activates left
extrastriate cortex. NeuroImage, 21, 829-839.
doi:10.1016/j.neuroimage.2003.10.002
Gran, L., & Fabbro, F. (1989). Cerebral lateralization for syntactic and
semantic components in L1 (Italian) and L2 (English) in interpreting
students: Training implications for simultaneous interpretation. Paper
presented at the Coming of age, Proceedings of the 30th Annual ATA
Conference.
Green, A., Nicholson, N. S., Vaid, J., White, N., & Steiner, R. (1990).
Hemispheric involvement in shadowing vs. interpretation: A
time-sharing study of simultaneous interpreters with matched bilin-
gual and monolingual controls. Brain and Language, 39, 107-133.
doi:10.1016/0093-934X(90)90007-4
Hugdahl, K., & Davidson, R. J. (2003). Brain asymmetry II. MA, Cam-
bridge: MIT Press.
Lambert, S. (1989). Simultaneous interpreters: One ear may be better
than two. Canadian Association of Translation Studies, TTR, 2, 109-
116.
Oldfield, R. C. (1971). The assessment and analysis of handedness: The
Edinburgh inventory. Neuropsychologia, 9, 97-113.
doi:10.1016/0028-3932(71)90067-4
Paradis, M. (1989). Bilingual and polyglot aphasia. In F. Boller & J.
Grafman (Eds.), Handbook of Neuropsychology, 2, 117-140.
Polk, T. A., Stallcup, M., Aguirre, G. K., Alsop, D. C., Esposito, M. D.,
Detre, J. A., et al. (2002). Neural specialization for letter recognition.
Journal of Cognitive Neuroscience, 14, 145-159.
doi:10.1162/089892902317236803
Proverbio, A. M., Čok, B., & Zani, A. (2002). Electrophysiological
measures of language processing in bilinguals. Journal of Cognitive
Neuroscience, 14, 994-1017. doi:10.1162/089892902320474463
Proverbio, A. M., Leoni, G., & Zani, A. (2004). Language switching
mechanisms in simultaneous interpreters: An ERP study. Neuropsy-
chologia, 42, 1636-1656.
doi:10.1016/j.neuropsychologia.2004.04.013
Proverbio, A. M., Adorni, R., & Zani, A. (2007). The organization of