Publications

Abstract

In a small village in the north of Bali called Bengkala, relatively many people inherit deafness. The Balinese therefore refer to this village as Desa Kolok, which means 'deaf village'. Connie de Vos studied Kata Kolok, the sign language of this village, and the ways in which the language recruits space to talk about both spatial and non-spatial matters. he small village community Bengkala in the north of Bali has almost 3,000 inhabitants. Of all the inhabitants, 57% use sign language, with varying degrees of fluency. But of this signing community (between 1,200 and 1,800 signers, depending on your definition of 'signer'), only 4% are deaf. So, not only do the deaf people of Bengkala use the sign language Kata Kolok, but also the majority of the hearing population.
"I've worked with deaf people from all over Asia, Europe, and also some signers in America," says Connie de Vos of MPI's Language and Cognition Department, and Centre for Language Studies (RU). "What sets apart this particular deaf village is that deaf individuals are highly integrated within the village clans. There is really a huge proportion of hearing signers." The sign language currently functions in all major aspects of village life and has been acquired from birth by multiple generations of deaf, native signers. According to De Vos, Kata Kolok is a fully-fledged sign language in every sense of the word. As a collaborative project, she has initiated inclusive deaf education within the village and now Kata Kolok is used as the primary language of instruction. De Vos' primary finding is that Kata Kolok discourse uses a different system of referring to space than other sign languages. Spatial relations are represented by a so-called "absolute frame of reference", based on geographic locations and wind directions. "All sign languages, as we know, use relative constructions for spatial relations. They use signs comparable to words like 'left' and 'right' instead of 'east' and 'west'. Kata Kolok does the latter. Kata Kolok signers appear to have an internal compass to continually register their position in space."De Vos is the first sign linguist who has documented Kata Kolok extensively. She spent more than a year in the village and collected over a hundred hours of video material of spontaneous conversations. "One of the things I've noticed is that language doesn't really emerge out of nothing," she says. "Signers adopt a local gesture system and transform it into a new and much more systematic sign language. A lot of the signs refer to concepts they're familiar with. That's why hearing signers have no difficulties in picking up Kata Kolok. Kata Kolok unites the hearing and the deaf.

Abstract

This dissertation focuses on syntactic comprehension problems in patients with Broca's aphasia from an electrophysiological perspective. The central objective of this dissertation was to further explore what syntax-related event-related brain potential (ERP) effects can reveal about the nature of the deficit that underlies syntactic comprehension problems in patients with Broca's aphasia. Chapter two to four describe experiments in which event-related brain potentials were recorded while subjects (Broca patients, non-aphasic patients with a right-hemisphere lesion, and healthy elderly controls) were presented with sentences that contained either violations of syntactic constraints or were syntactically correct. Chapter two investigates ERP effects of subject-verb agreement violations in the different subject groups, and seeks to answer the following questions: Do agrammatic comprehenders show sensitivity to subject-verb agreement violations as indicated by a syntax-related ERP effect? In addition, does the severity of the syntactic comprehension impairment in the Broca patients affect the ERP responses? Chapter three describes an investigation of whether Broca patients show sensitivity to violations of word order as indicated by a syntax-related ERP effect, and whether the ERP responses in the Broca patients are affected by the severity of their syntactic comprehension impairment. Chapter four reports on ERP effects of violations of word-category. In addition, also a semantic violation condition was added to track possible dissociations in the sensitivity to semantic and syntactic information in the Broca patients. Chapter five describes the development of a paradigm in which the electrophysiological approach and the classical sentence-picture matching approach are combined. In this chapter, the ERP method is applied to study on-line thematic role assignment in Broca patients during sentence-picture matching. Also the relation between ERP effects and behavioral responses is pursued. Finally, Chapter 6 provides a summary of the main findings of the experiments and a general discussion.

Abstract

Many people speak a second language next to their mother tongue. How do they learn this language and how does the brain process it compared to the native language? A second language can be learned without explicit instruction. Our brains automatically pick up grammatical structures, such as word order, when these structures are repeated frequently during learning. The learning takes place within hours or days and the same brain areas, such as frontal and temporal brain regions, that process our native language are very quickly activated. When people master a second language very well, even the same neuronal populations in these language brain areas are involved. This is especially the case when the grammatical structures are similar. In conclusion, it appears that a second language builds on the existing cognitive and neural mechanisms of the native language as much as possible.

Abstract

In recent decades, neuroimaging studies on the neural infrastructure of language are usually (or mostly) conducted with certain on-line language processing tasks. These functional neuroimaging studies helped to localize the language areas in the brain and to investigate the brain activity during explicit language processing. However, little is known about what is going on with the language areas when the brain is ‘at rest’, i.e., when there is no explicit language processing running. Taking advantage of the fcMRI and DTI techniques, this thesis is able to investigate the language function ‘off-line’ at the neuronal network level and the connectivity among language areas in the brain. Based on patient studies, the traditional, classical model on the perisylvian language network specifies a “Broca’ area – Arcuate Fasciculus – Werinicke’s area” loop (Ojemann 1991). With the help of modern neuroimaging techniques, researchers have been able to track language pathways that involve more brain structures than are in the classical model, and relate them to certain language functions. In such a background, a large part of this thesis made a contribution to the study of the topology of the language networks. It revealed that the language networks form a topographical functional connectivity pattern in the left hemisphere for the right-handers. This thesis also revealed the importance of structural hubs, such as Broca’s and Wernicke’s areas, which have more connectivity to other brain areas and play a central role in the language networks. Furthermore, this thesis revealed both functionally and structurally lateralized language networks in the brain. The consistency between what is found in this thesis and what has been known from previous functional studies seems to suggest, that the human brain is optimized and ‘ready’ for the language function even when there is currently no explicit language-processing running.