Ilhan Raman

On the age-of-acquisition effects in word naming and orthographic transparency: Mapping specific or universal?

One account for age-of-acquisition (AoA) effects in word naming is the arbitrary mapping hypothesis proposed by Ellis and Lambon Ralph (2000), who argue that these should be stronger when arbitrary rather than consistent mappings between representations are involved. The arbitrary mapping hypothesis predicts that AoA effects should be reduced when reading words in languages with transparent orthography-to-phonology mappings. This prediction was put to the test in the transparent orthography of Turkish. Early and late acquired Turkish words matched on frequency, imageability, initial phoneme, and length were presented for naming. Early acquired words were read aloud reliably faster than late acquired words, thus failing to support the claims of the arbitrary mapping hypothesis. The implications of this finding are discussed within current theoretical frameworks accounting for AoA effects and orthographic transparency.

On the control of visual word recognition: Changing routes versus changing deadlines

Two different accounts have been proposed to explain the fact that (1) an effect of word frequency is present when readers of transparent orthographies read only words aloud and (2) the effect of word frequency is eliminated when subjects name words and nonwords mixed together in a single block. In the route-shifting account, subjects shift from using a lexical route that can read only words to using a nonlexical route that can read both words and nonwords via the use of sublexical spelling-sound correspondences (hence, no word frequency effect). The essence of the second, time criterion account is that the elimination of the word frequency effect is determined by the speed with which the nonwords are processed, because subjects attempt to homogenize the point in time at which they release an articulation. These two different accounts are pitted against each other in a series of naming experiments utilizing the transparent Turkish orthography. A word frequency effect persists even when words and nonwords are mixed together, provided that nonword sets are matched so as to be named as quickly as the high-frequency words and as slowly as the low-frequency words, respectively. This result is argued to be consistent with the time criterion account, but not with the unadorned route-shifting account.

Semantic effects as a function of reading skill in word naming of a transparent orthography

The highly transparent Turkish orthography was employed to examine imageability in relation to level of skill in two experiments. In experiment 1, previously skilled readers (n = 24)named 40 high frequency and 40 low frequency words manipulatedfactorially with imageability. A significant main effect was onlyfound for frequency. In experiment 2, a total of 44 adult Turkishreaders (16 very skilled and 28 skilled) named the same stimulias in experiment 1. The results showed an expected main effectfor skill and frequency. However, whilst the main effect forimageability was nonsignificant, a 2-way interaction of skill byimageability and a 3-way interaction of skill by imageability byfrequency were found to be significant. Very skilled readersnamed high imageable low frequency words significantly fasterthan matched low imageable low frequency words. Insofar as poorreaders are concerned the results are contradictory to previousfindings in English whilst data from highly skilled participantsare in line with those reported for skilled readers for English.Implications of these findings on the existing literature arediscussed.

What Is the Cognitive System's Preferred Route for Deriving Phonology from Print?

The present study examined the manner in which Turkish readers read aloud words printed in shallow (transparent) Turkish orthography. The first experiment showed that when the set consists of only word stimuli there is a significant word-frequency effect. This indicates that readers had made reference to lexical information for naming. The result of a second experiment, on the other hand, showed that when an equal number of nonwords are embedded in the stimulus set the word-frequency effect disappears. This indicates that readers had made reference to nonlexical information for naming. These results support the ideas that: (a) the preferred route for naming amongst readers of Turkish script is lexical, regardless of the orthographic-phonological transparency; and (b) the naming process is indeed a flexible one in which task demands may affect the nature of the route used for naming. The above findings are discussed in relation to research on shallow and deep (nonshallow) orthographies .

Deep dysgraphia in Turkish

Deep dysgraphic patients make semantic errors when writing to dictation and they cannot write nonwords. Extant reports of deep dysgraphia come from languages with relatively opaque orthographies. Turkish is a transparent orthography because the bidirectional mappings between phonology and orthography are completely predictable. We report BRB, a biscriptal Turkish-English speaker who has acquired dysgraphia characterised by semantic errors as well as effects of grammatical class and imageability on writing in Turkish. Nonword spelling is abolished. A similar pattern of errors is observed in English. BRB is the first report of acquired dysgraphia in a truly transparent writing system. We argue that deep dysgraphia results from damage to the mappings that are common to both languages between word meanings and orthographic representations.

Bilingual deep dysphasia

We report B.R.B., a bilingual Turkish–English speaker with deep dysphasia. B.R.B. shows the typical pattern of semantic errors in repetition with effects of lexicality and imageability on performance in both languages. The question we asked is whether language type (Turkish or English) or language status—that is, first acquired (L1) or second acquired (L2)—has a greater impact on performance. Results showed that repetition in L1 (Turkish) was better than that in L2 (English). We also observed effects of language status on oral reading, writing to dictation, and naming (spoken and written) with greater impairment to repetition than other tasks in both languages. An additional finding was that spoken-word translation in both directions was worse than written-word translation, and word class had an effect on translation from L1 to L2. We argue that interactive activation models of deep dysphasia could explain deep dysphasia in bilingual speakers and interactions between task and language, if the weighted connections that support language processing in L2 are assumed to be weaker, thus causing rapid phonological decay to have more impact on task performance in L2. Implications of the results for models of bilingual language processing are also considered.

A standardized set of 260 pictures for Turkish: Norms of name and image agreement, age of acquisition, visual complexity, and conceptual familiarity

In the present study, normative data in Turkish are presented for the 260 color versions of the original Snodgrass and Vanderwart (1980) picture set for the first time. Norms are reported for name and image agreement, age of acquisition (AoA), visual complexity, and conceptual familiarity, together with written word frequency, and numbers of letters and syllables. We collected data from 277 native Turkish adults in a variety of tasks. The results indicated that, whilst several measures displayed language-specific variation, we also reported what seem to be language-independent—that is, universal—measures that show a systematic relationship across several languages. The implications of the reported measures in the domain of psycholinguistic research in Turkish and for wider cross-linguistic comparisons are discussed.

The role of age of acquisition in picture and word naming in dyslexic adults.

To date, there has been numerous reports that early acquired pictures and words are named faster than late acquired pictures and words in normal reading but it is not established whether age of acquisition (AoA) has the same impact on adult dyslexic naming, especially in a transparent orthography such as Turkish. Independent ratings were obtained for AoA, frequency, name agreement, and object familiarity in Turkish for all items in the Snodgrass and Vanderwart line drawing set. Dyslexic (N= 15) and non-dyslexic (N= 15) university undergraduates were asked to name 30 early acquired and 30 late acquired pictures and picture names standardized and selected from these norms. As predicted, there were main effects for (a) AoA with reaction times (RTs) for Early items named faster than Late items, (b) reader status with non-dyslexic students faster than dyslexic students, and (c) stimuli types with pictures named slower than words. A two-way interaction between reader status and stimuli type was also significant. Implications of the results for theoretical frameworks of AoA within the cognitive architecture and normal and impaired models of reading are discussed.

Deep dysphasia in Turkish.

Deep dysphasia is a language impairment that is defined by impaired repetition. In this study we report a bilingual Turkish-English patient BRB who shows many of the features of deep dysphasia in both languages. BRB was given lexical and non-lexical processing tasks including oral reading, repetition and writing to dictation manipulating several variables (AoA, regularity, imageability, grammatical class) in Turkish (L1) and English (L2). BRB was also asked to translate orally and in writing both high and low frequency and high and low imageability words from L1 to L2 and from L2 to L1. Significant main effects of language and task as well as interactions between language and task were observed e.g., BRB’s repetition, reading and writing was better in L1 than L2 object naming was better in L2 than L1 but only with high imageability words. We argue that impaired language processing in deep dysphasia arises from the under-activation of phonological representations. We propose that current models of deep dysphasia require modification to explain bilingual deep dysphasia and also interpret BRB’s performance using a model of bilingual lexical processing.

Age of Acquisition (AoA) effect in monolingual Russian and bilingual Russian (L1) - English (L2) speakers in a free recall task

ABSTRACT AoA is a unique psycholinguistic variable because of its link to the semantic architecture of the mental lexicon. The role of AoA on free recall has been examined in English and recently in Turkish with contradictory outcomes. The present study extends Raman et al.’s (under revision, Differential effects of age of acquisition and frequency on memory: Evidence from free recall of pictures and words in Turkish) study to monolingual Russian and bilingual Russian (L1)-English (L2) speakers in order to understand the extent to which AoA affects free recall. Participants were allocated to either picture or word condition and subsequently to either pure list or mixed list condition. Both monolingual Russian (N = 42) and bilingual (N = 40) Russian (L1)-English (L2) data show a robust main effect for AoA in free recall irrespective of list type for words and for pictures and no significant interactions. Overall, early acquired words and pictures had an advantage over late acquired items. These findings are contrary to what has been reported in the literature for monolingual English speakers but in line with findings for Turkish and will be discussed within the monolingual and bilingual theoretical frameworks.