Brodmann's Interactive
Atlas
AREA 44
Broca's Area
(Inferior frontal gyrus - Pars opercularis)
Associated
Functions
- Language (left hemisphere in majority of people) (Many
articles, in general)
- Response to unintelligible speech (16781167)
- Expression of emotional information (Right) (15670701)
- Perception of prosodic information (intonation) in speech
(Right) (15670701,
15670670)
- Attention in speech processing (14754865)
- Sentence comprehension (11896643)
- Internally-specified word generation (9710491)
- Memory
- Motor
- Others
Reviewer's note
From the traditional point of view, Broca's area
corresponds to BA 44, but several contemporary authors also include BA
45. It can be conjectured that in the future, the most
anterior part of the insula could also be included in the Broca’s
area, given its participation in the praxis of speech (motor speech
programming). Different proposals have been presented to explain
language disturbances in so-called Broca’s aphasia; different
hypotheses have attempted to postulate a core BA44 function, including:
binding the elements of the language, selecting information among
competing sources, generating/extracting action meanings; sequencing
motor/expressive elements; cognitive control mechanism for the
syntactic processing of sentences; construction of higher parts of the
syntactic tree in speech production; and verbal working memory.
Functional studies have further improved our understanding of
BA44. Although the core BA44 function remain elusive, fluency and
sequencing may potentially account for many of the functions in which
BA44 participates. The suggestion that BA44 includes mirror neurons for
expressive movements is particularly provocative and may enlighten the
question of inner speech (e.g., internally generated language).
Functional studies have also contributed to further understand right
BA44,
which seemingly participates in perception and expression of prosodic
and
emotional information. From the perspective of the lesional model,
unfortunately just few studies have analyzed the clinical disturbances
associated with right BA44. Functional studies have also disclosed the
participation of BA44 in a diversity of tasks that are difficult to
interpret with our current understanding of the brain, such as pain
anticipation, perception of tactile stimulation, motion after-effect,
object manipulation, smelling familiar odors, and music enjoyment; in
those cases, BA44 activation is just an additional element in a complex
brain network; it may be suggested that some internal verbalization can
account for BA44 involvement in these unexpected activities. Its
participation in working memory may also reflect the internal rehearsal
of the information.