The battle for Broca's region

The intense effort to characterize Broca's region has produced many views on its anatomy and function. Here, we present the leading approaches and consider ways to adjudicate among them empirically. Anatomically, we focus on the cytoarchitecture of Brodmann areas 44 and 45, which constitute Broca's region. Functionally, we discuss four views: action perception, working memory, syntactic complexity and syntactic movement. We compare these views, reflect on how they can be distinguished experimentally and review relevant aphasia and functional magnetic resonance imaging (fMRI) studies. Although no single hypothesis accounts for all of the data, the role of Broca's region in language comprehension is best explained by the syntactic movement account. This conclusion opens the door for an attempt to define general principles for the neural representation of linguistic knowledge.     

Aphasia in Turkish: speech production in Broca's and Wernicke's patients

Turkish speech production was studied in 7 Broca's and 10 Wernicke's aphasics. Turkish is an agglutinative language, with few free-standing closed-class morphemes. The speech of Broca's patients was not telegraphic; although nonfluent, noun and verb suffixes were used appropriately. The speech of Wernicke's aphasics was fluent, using a wide range of often inappropriate forms. Both groups used appropriate nominal morphology. Broca's patients used a limited set of verb forms in contextually appropriate fashion. Wernicke's patients used a wide range of verb forms, all morphosyntactically correct, but often semantically anomalous. Both groups retained canonical subject-object-verb word order and controlled various types of pragmatically appropriate word order variation. It is proposed that aphasic speech patterns reflect retrieval problems rather than impairment of a portion of the language system.     

Architecture and organizational principles of Broca's region

Identifying cortical areas for language and speech processing is a prerequisite for cognitive neuroscience and clinical research. Although Broca's region is one of the essential nodes in the language network, its anatomical constituents are ill-defined and multiple definitions of Broca's region exist. Sanides' concept of microstructural gradations interpreted Broca's region as developing from neighboring motor, dorsolateral-prefrontal, and insular cortices. Recent mapping approaches based on cytoarchitecture, transmitter receptor distribution, and connectivity revealed a highly differentiated segregation of this region far beyond Brodmann's classical scheme. This novel segregational concept of structural and functional architecture more adequately reflects the various functions of Broca's region in cognitive and/or linguistic processes.     

Motor functions of the Broca's region

Broca's region in the dominant cerebral hemisphere is known to mediate the production of language but also contributes to comprehension. This region evolved only in humans and is constituted of Brodmann's areas 44 and 45 in the inferior frontal gyrus. There is, however, evidence that Broca's region overlaps, at least in part, with the ventral premotor cortex. We summarize the evidence that the motor related part of Broca's area is localized in the opercular portion of the inferior frontal cortex, mainly in area 44 of Brodmann. According to our own data, there seems to be a homology between Brodmann area 44 in humans and the monkey area F5. The non-language related motor functions of Broca's region comprise complex hand movements, associative sensorimotor learning and sensorimotor integration. Brodmann's area 44 is also a part of a specialized parieto-premotor network and interacts significantly with the neighboring premotor areas.     

Relationship between language competence and emotional competence in middle childhood

Research on children's emotional competence has received considerable attention in the last decade, including the role of language. Language competence (LC) and emotional competence (EC) comprise multiple components. These components and their specific interrelations have not been studied sufficiently. In our study, we examined relations between multiple components of LC and EC in a sample of 210 school-age children. Five measures represented LC: receptive vocabulary, verbal fluency, literacy, narrative structure, and the narrative use of evaluative devices. Four measures represented EC: expressive emotion vocabulary, declarative emotion knowledge, awareness of mixed emotions, and facial emotion recognition. Results showed strong positive correlations between LC and EC ranging between r = .12 and r = .45. In particular, receptive vocabulary and literacy were closely related to emotion knowledge and awareness of mixed emotions. A confirmatory factor analysis revealed that there is a common general ability factor for LC and EC. We discuss why receptive vocabulary and literacy might be so strongly related to emotion knowledge in school-age children. Our findings have implications for developmental psychologists, educational research, and speech-language pathologists.     

Controversies about CP: a comparison of language acquisition and language impairments in Broca's aphasia

In both language acquisition research and the study of language impairments in Broca's aphasia there is an ongoing debate whether or not phrase-structure representations contain the Complementizer Phrase (CP) layer. To shed some light on this debate, I will provide data on German child language and on German agrammatic Broca's aphasia. Analyses of subordinate clauses, wh-questions, and verb placement indicate that early child grammars do not generate the CP layer yet, whereas the ability to project the CP layer is retained in agrammatism.     

Speech and language functions that require a functioning Broca's area

A number of previous studies have indicated that Broca's area has an important role in understanding and producing syntactically complex sentences and other language functions. If Broca's area is critical for these functions, then either infarction of Broca's area or temporary hypoperfusion within this region should cause impairment of these functions, at least while the neural tissue is dysfunctional. The opportunity to identify the language functions that depend on Broca's area in a particular individual was provided by a patient with hyperacute stroke who showed selective hypoperfusion, with minimal infarct, in Broca's area, and acutely impaired production of grammatical sentences, comprehension of semantically reversible (but not non-reversible) sentences, spelling, and motor planning of speech articulation. When blood flow was restored to Broca's area, as demonstrated by repeat perfusion weighted imaging, he showed immediate recovery of these language functions. The identification of language functions that were impaired when Broca's area was dysfunctional (due to low blood flow) and recovered when Broca's area was functional again, provides evidence for the critical role of Broca's area in these language functions, at least in this individual.     

Analytical competence and language impairment in aphasia

Matched groups of Broca's and Wernicke's aphasics, brain-damaged patients without aphasia and chronic schizophrenics were tested in a nonverbal matching task where the subject had to indicate which of two pictures was more closely linked to a clue picture. Eight additional verbal and nonverbal reference tasks were administered. Both aphasic groups performed worse than brain-damaged controls when the identification of individual attributes or actions shared by clue and referent was required, but were unimpaired when the two had a set of referential-situational associations in common. Factor analyses resulted for both groups in two factors, one of which represents general Language Impairment. For the Broca's aphasics this factor was closely related to general organic deficit as measured by the Trail Making Test; for the Wernicke's aphasics it was associated with tasks which might be considered illustrative of analytical competence in isolating and comparing individual features of objects or concepts.     

Nasal consonant production in Broca's and Wernicke's aphasics: speech deficits and neuroanatomical correlates

The present study investigated the articulatory implementation deficits of Broca's and Wernicke's aphasics and their potential neuroanatomical correlates. Five Broca's aphasics, two Wernicke's aphasics, and four age-matched normal speakers produced consonant-vowel-(consonant) real word tokens consisting of [m, n] followed by [i, e, a, o, u]. Three acoustic measures were analyzed corresponding to different properties of articulatory implementation: murmur duration (a measure of timing), amplitude of the first harmonic at consonantal release (a measure of articulatory coordination), and murmur amplitude over time (a measure of laryngeal control). Results showed that Broca's aphasics displayed impairments in all of these parameters, whereas Wernicke's aphasics only exhibited greater variability in the production of two of the parameters. The lesion extent data showed that damage in either Broca's area or the insula cortex was not predictive of the severity of the speech output impairment. Instead, lesions in the upper and lower motor face areas and the supplementary motor area resulted in the most severe implementation impairments. For the Wernicke's aphasics, the posterior areas (superior marginal gyrus, parietal, and sensory) appear to be involved in the retrieval and encoding of lexical forms for speech production, resulting in increased variability in speech production.     

The neurology of syntax: language use without Broca's area

A new view of the functional role of the left anterior cortex in language use is proposed. The experimental record indicates that most human linguistic abilities are not localized in this region. In particular, most of syntax (long thought to be there) is not located in Broca's area and its vicinity (operculum, insula, and subjacent white matter). This cerebral region, implicated in Broca's aphasia, does have a role in syntactic processing, but a highly specific one: It is the neural home to receptive mechanisms involved in the computation of the relation between transformationally moved phrasal constituents and their extraction sites (in line with the Trace-Deletion Hypothesis). It is also involved in the construction of higher parts of the syntactic tree in speech production. By contrast, basic combinatorial capacities necessary for language processing--for example, structure-building operations, lexical insertion--are not supported by the neural tissue of this cerebral region, nor is lexical or combinatorial semantics. The dense body of empirical evidence supporting this restrictive view comes mainly from several angles on lesion studies of syntax in agrammatic Broca's aphasia. Five empirical arguments are presented: experiments in sentence comprehension, cross-linguistic considerations (where aphasia findings from several language types are pooled and scrutinized comparatively), grammaticality and plausibility judgments, real-time processing of complex sentences, and rehabilitation. Also discussed are recent results from functional neuroimaging and from structured observations on speech production of Broca's aphasics. Syntactic abilities are nonetheless distinct from other cognitive skills and are represented entirely and exclusively in the left cerebral hemisphere. Although more widespread in the left hemisphere than previously thought, they are clearly distinct from other human combinatorial and intellectual abilities. The neurological record (based on functional imaging, split-brain and right-hemisphere-damaged patients, as well as patients suffering from a breakdown of mathematical skills) indicates that language is a distinct, modularly organized neurological entity. Combinatorial aspects of the language faculty reside in the human left cerebral hemisphere, but only the transformational component (or algorithms that implement it in use) is located in and around Broca's area.     

The role of Broca's area in speech perception: evidence from aphasia revisited

Motor theories of speech perception have been re-vitalized as a consequence of the discovery of mirror neurons. Some authors have even promoted a strong version of the motor theory, arguing that the motor speech system is critical for perception. Part of the evidence that is cited in favor of this claim is the observation from the early 1980s that individuals with Broca’s aphasia, and therefore inferred damage to Broca’s area, can have deficits in speech sound discrimination. Here we re-examine this issue in 24 patients with radiologically confirmed lesions to Broca’s area and various degrees of associated non-fluent speech production. Patients performed two same-different discrimination tasks involving pairs of CV syllables, one in which both CVs were presented auditorily, and the other in which one syllable was auditorily presented and the other visually presented as an orthographic form; word comprehension was also assessed using word-to-picture matching tasks in both auditory and visual forms. Discrimination performance on the all-auditory task was four standard deviations above chance, as measured using d′, and was unrelated to the degree of non-fluency in the patients’ speech production. Performance on the auditory–visual task, however, was worse than, and not correlated with, the all-auditory task. The auditory–visual task was related to the degree of speech non-fluency. Word comprehension was at ceiling for the auditory version (97% accuracy) and near ceiling for the orthographic version (90% accuracy). We conclude that the motor speech system is not necessary for speech perception as measured both by discrimination and comprehension paradigms, but may play a role in orthographic decoding or in auditory–visual matching of phonological forms.     

Musical competence and phoneme perception in a foreign language

We investigated whether musical competence was associated with the perception of foreign-language phonemes. The sample comprised adult native-speakers of English who varied in music training. The measures included tests of general cognitive abilities, melody and rhythm perception, and the perception of consonantal contrasts that were phonemic in Zulu but not in English. Music training was associated positively with performance on the tests of melody and rhythm perception, but not with performance on the phoneme-perception task. In other words, we found no evidence for transfer of music training to foreign-language speech perception. Rhythm perception was not associated with the perception of Zulu clicks, but such an association was evident when the phonemes sounded more similar to English consonants. Moreover, it persisted after controlling for general cognitive abilities and music training. By contrast, there was no association between melody perception and phoneme perception. The findings are consistent with proposals that music- and speech-perception rely on similar mechanisms of auditory temporal processing, and that this overlap is independent of general cognitive functioning. They provide no support, however, for the idea that music training improves speech perception.     

Segmentation of speech in a foreign language

The subjects' ability to segment foreign speech was examined. Naturalness judgments regarding three syntactically defined pauses [between constituents (noun and verb phrases), words, or syllables] were obtained using a paired-presentation, forced-choice paradigm. It was hypothesized that segmentation skill developed through exposure to lexical and syntactic markers. Teh existence and effect of such markers was investigated by assigning subjects to various exposure conditions.Results indicated that lexical and syntactic markers exist and can be utilized by subjects in segmenting speech. Contrary to previous research, however, exposure did not facilitate performance. All groups discriminated constituents from either words or syllables, and words from syllables. Results were interpreted as reflecting the interdependence of syntax and suprasegmental phonology. Results challenged the credibility of traditional associationist accounts of language acquisition and speech perception. Results were discussed in the context of Martin's theory of the rhythmic structure of speech.     

Messianic language in trans public speech*

ABSTRACT

This essay examines how two trans public figures, Lou Sullivan and Jennifer Finney Boylan, try to realize the need for transgender legibility through messianic rhetoric. Messianism is a site of contention in queer theory, between advocates for either antirelational queer theory or queer utopianism. This essay sees messianic rhetoric as a strategy found in the public speech and writing of Sullivan and Boylan, each of whom instrumentalize it to achieve legibility. Such rhetoric works to the political end of broader transgender acceptance. However, it also relies upon a flattening of trans life into a monolith. Messianic rhetoric legitimates a singular narrative of “how to be trans” through excluding other possibilities. Public speech that rejects this universalizing messianic impulse is possible. The zine “Fucking Trans Women” represents such a possibility, focusing attention on experience and pleasure over narrative linearity, thus providing one path forward for trans public speech.     

Patterns of figurative language competence in adult speakers

Summary In an attempt to discover patterns of adult figurative language use, preference and comprehension, 30 Ss were asked to complete 4 different tasks: a composition, a test of simile preference, a test of simile production, and a test of metaphoric comprehension. Each test provided scores for both novel and clichéed usage. The composition task was also scored for total words while preference and production tasks were scored for literal usage, thus producing a total of 11 dependent variables across the complete set of tasks.Results revealed that Ss selected a higher number of novel figures under choice relative to production conditions. Correlational results revealed relationships across all 4 tasks for the categories of novel and frozen usage although certain tasks (i.e., simile preference and production) were more sensitive to novel diction while others (comprehension) were more sensitive to frozen diction. Within-task correlations, on the other hand, showed unique patterns for each of the tasks. Factor analyses of these correlations were found to produce a series of consistent three-factor solutions with the first of these factors concerned primarily with novel diction, the second with both novel and frozen comprehension, and the third primarily with frozen diction.Taken in combination, present results were interpreted to mean that while the distinction between novel and frozen is a meaningful one, specific task requirements can and do moderate the pattern of relationships obtained. This suggests that figurative language competence may not be a unitary process but one that is strongly affected by specific task and situational constraints and that future work, both methodological and theoretical, must take these factors into account.     

Psychiatric risk in children with speech and language disorders

Based on an initial community sample of 1,655 5-year-old children, this report utilized the risk statistic to estimate a child's risk for developing a psychiatric disturbance depending on his or her status as speech/language-impaired. Results showed that risk estimates varied as a function of gender and source of information (teacher, parent, psychiatric reports). Overall, speech- and language-impaired children had a higher risk for developing a psychiatric disturbance compared with normal language controls, with speech/language-impaired girls being at greater risk than boys.     

Pitch and timing abilities in inherited speech and language impairment

Members of the KE family who suffer from an inherited developmental speech-and-language disorder and normal, age-matched, controls were tested on musical abilities, including perception and production of pitch and rhythm. Affected family members were not deficient in either the perception or production of pitch, whether this involved either single notes or familiar melodies. However, they were deficient in both the perception and production of rhythm in both vocal and manual modalities. It is concluded that intonation abilities are not impaired in the affected family members, whereas their timing abilities are impaired. Neither their linguistic nor oral praxic deficits can be at the root of their impairment in timing; rather, the reverse may be true.