The Bilingual Brain: Bilingual Aphasia

204 FRANCO FABBRO
thought to be due to the ‘‘takeover’’ of linguistic functions by the contralateral hemisphere
or by undamaged areas within the same hemisphere (Bychowsky, 1919/1983;
Cappa, 1998). Improvement in communication skills may probably depend on the
application of explicit compensatory strategies (Paradis, 1994; Paradis & Gopnik,
1997). Recovery, either spontaneous or following rehabilitation, may continue also
during the late phase, though generally less intensively than during the lesion phase.
Patients should be periodically reassessed so as to reexamine recovery patterns and
possibly revise the rehabilitation program. The most common patterns of recovery,
described by Pitres (1895) in the first monograph on bilingual aphasia ever published,
are (1) parallel recovery, when both languages are recovered simultaneously;
(2) selective recovery, when only one language slowly comes back and the other is
never recovered; and (3) successive recovery, when one language improves before
the other(s).
Language Recovery in Polyglot Aphasics
When bilinguals or polyglots suffer a brain insult affecting language areas, they
may lose the ability to use all languages they knew and exhibit the same type of
aphasia in all languages. Subsequent recovery may be parallel in all languages. In a
study on the literature of bilingual aphasia published in 1977, Paradis stated that 40%
of the reported cases of polyglot aphasics exhibited parallel recovery of languages.
It should be noted, however, that these statistics are based on clinical case histories
which have been published and, thus, are the most atypical. Paradis put forward the
hypothesis that this type of recovery is even more frequent because descriptions of
single clinical cases of polyglot aphasics with parallel language recovery are very
rare, since neurologists and neuropsychologists tend to describe ‘‘exceptional’’ cases
only, as they can more easily be published (Paradis, 1977). This is one of the reasons
why over 10 years ago Paradis started an international project on bilingual aphasia
in Canada, which is still operative and sees the participation of numerous researchers
from all over the world. This study also includes bilingual aphasic patients with any
type of language disorders so as to have a large number of subjects and, thus, more
reliable statistical data.
In some cases, aphasia affects only one of the languages known by the patient. In
his study of 1895, Pitres was the first to draw attention to the fact that the dissociation
of the languages affected by aphasia was not an exceptional phenomenon, but rather
ordinary. Pitres described seven clinical cases of patients exhibiting differential recovery
of the two languages they spoke. On the basis of the frequency of dissociation,
Pitres put forward hypotheses on the causes that might determine a better recovery
in one language. He suggested that patients tended to recover the language that was
most familiar to them prior to the insult. This hypothesis was subsequently called
Pitres’ rule. In proposing his theory, Pitres referred to a work by Ribot in which it
was claimed that, in the case of memory disorders, the general rule held that the new
deteriorates earlier than the old. Subsequently, numerous neurologists compared and
contrasted the so-called Pitres’ rule (recovery of the most familiar language) with
‘‘Ribot’s law’’ (recovery of the native language), but it should be noted that none of
the two authors ever formulated a ‘‘rule’’ on language recovery in bilingual aphasics.
In his work, Pitres proposed a reasonable explanation of language recovery in
aphasics. He maintained that the recovery pattern could occur only if the lesion had
not destroyed language centers, but only temporarily inhibited them through pathological
inertia. In Pitres’ opinion, the patient generally recovered the most familiar
language because the neural elements subserving it were more firmly associated. If
the patient had become aphasic owing to ‘‘functional inertia’’ of the language areas,