We discuss the causative-inchoative alternation in Turkish Sign Language (Türk Isaret Dili -- TID), and the age of acquisition effects on multi-predicate, complex constructions that are observed in both causative and inchoative events. We present a picture-description task performed by 24 adult signers, half of which were exposed to TID from birth…

Using a free-recall paradigm, we explored the effects of age of acquisition and category size on verbal fluency in Turkish Sign Language (Türk Isaret Dili [TID]). We studied the semantic and phonological fluency task performances of deaf native and deaf late adult signers. We measured the number of correct responses and performed a time course…

Linguistic expressions of locative spatial relations in sign languages are mostly visually motivated representations of space involving mapping of entities and spatial relations between them onto the hands and the signing space. These are also morphologically complex forms. It is debated whether modality-specific aspects of spatial expressions…

Developmental psychology plays a central role in shaping evidence-based best practices for prelingually deaf children. The Auditory Scaffolding Hypothesis (Conway et al., 2009) asserts that a lack of auditory stimulation in deaf children leads to impoverished implicit sequence learning abilities, measured via an artificial grammar learning (AGL)…

Background: Deafness has an adverse impact on children's ability to acquire spoken languages. Signed languages offer a more accessible input for deaf children, but because the vast majority are born to hearing parents who do not sign, their early exposure to sign language is limited. Deaf children as a whole are therefore at high risk of language…

Language acquisition involves learning not only grammatical rules and a lexicon but also what people are intending to convey with their utterances: the semantic/pragmatic component of language. In this article we separate the contributions of linguistic development and cognitive maturity to the acquisition of the semantic/pragmatic component of…

Does spatial language influence how people think about space? To address this question, we observed children who did not know a conventional language, and tested their performance on nonlinguistic spatial tasks. We studied deaf children living in Istanbul whose hearing losses prevented them from acquiring speech and whose hearing parents had not…

Child development researchers often discuss a "two-word" stage during language acquisition. However, there is still debate over whether the existence of this stage reflects primarily cognitive or linguistic constraints. Analyses of longitudinal data from two Deaf children, Mei and Cal, not exposed to an accessible first language (American Sign…

We investigated the functional organisation of neural systems supporting language production when the primary language articulators are also used for meaningful, but nonlinguistic, expression such as pantomime. Fourteen hearing nonsigners and 10 deaf native users of American Sign Language (ASL) participated in an H[subscript 2][superscript…

Age of acquisition (AoA) effects have been used to support the notion of a critical period for first language acquisition. In this study, we examine AoA effects in deaf British Sign Language (BSL) users via a grammaticality judgment task. When English reading performance and nonverbal IQ are factored out, results show that accuracy of…

Using functional magnetic resonance imaging (fMRI), we neuroimaged deaf adults as they performed two linguistic tasks with sentences in American Sign Language, grammatical judgment and phonemic-hand judgment. Participants' age-onset of sign language acquisition ranged from birth to 14 years; length of sign language experience was substantial and…

This study explores the form of representational gestures produced by forty-five hearing children (age range 2 ; 0-3 ; 1) asked to label pictures in words. Five pictures depicting objects and five pictures depicting actions which elicited more representational gestures were chosen for more detailed analysis. The range of gestures produced for each…

This is a dissertation study focusing on the ability of deaf children to fast map common and newly learned novel fingerspelled words through a training task. It also explored the relationship between the ability to learn fingerspelled words and the children's reading and vocabulary skills. Learning was assessed using five domains: imitation,…

In the course of language development children must solve arbitrary form-to-meaning mappings, in which semantic components are encoded onto linguistic labels. Because sign languages describe motion and location of entities through iconic movements and placement of the hands in space, child signers may find spatial semantics-to-language mapping…

"Theory of mind" development is now an important research field in deaf studies. Past research with the classic false belief task has consistently reported a delay in theory of mind development in deaf children born of hearing parents, while performance of second-generation deaf children is more problematic with some contradictory results. The…