Age of acquisition, word frequency, and the role of phonology in the lexical decision task

Corpus-based age of word acquisition: Does it support the validity of adult age-of-acquisition ratings?

Age of acquisition (AoA) is presumed to reflect the age or relative order in which words are learned, but is often measured using adult ratings or adult-reported observations and might thus reflect more about the adult language than about the acquisition process. Objective AoA estimates are often limited to words whose referents can be shown in pictures. We created a corpus-derived AoA estimate based on first word occurrences in a longitudinal corpus of child English, and evaluated its reliability and validity against other measures of AoA. Then we used these different measures as concurrent predictors of adult lexical decision times. Our results showed adequate reliability and good relations with other AoA measures, especially with parent-reported AoA (r = 0.56). Corpus AoA did not predict unique variance in lexical decision times, while adult AoA ratings and parent-reported AoA did. We argue that this pattern is due to two factors. First, the adult AoA ratings and parent-reported AoA are confounded with adult memory, lexical processing and reading difficulty variables. Second, the adult AoA ratings are related to actual age of acquisition only for words acquired during later preschool and school age. Our analyses support the utility of corpus-derived AoA estimates as an objective measure of acquisition age, especially for early-acquired words.

Dopamine-Related Reduction of Semantic Spreading Activation in Patients With Parkinson's Disease

Impaired performance in verbal fluency (VF) tasks is a frequent observation in Parkinson's disease (PD). As to the nature of the underlying cognitive deficit, it is commonly attributed to a frontal-type dysexecutive syndrome due to nigrostriatal dopamine depletion. Whereas dopaminergic medication typically improves VF performance in PD, e.g., by ameliorating impaired lexical switching, its effect on semantic network activation is unclear. Data from priming studies suggest that dopamine causes a faster decay of semantic activation spread. The aim of the current study was to examine the impact of dopaminergic medication on the dynamic change of word frequency during VF performance as a measure of semantic spreading activation. To this end, we performed a median split analysis of word frequency during phonemic and semantic VF task performance in a PD group tested while receiving dopaminergic medication (ON) as well as after drug withdrawal (i.e., OFF), and in a sample of age-matched healthy volunteers (both groups n = 26). Dopaminergic medication in the PD group significantly affected phonemic VF with improved word production as well as increased error-rates. The expected decrease of word frequency during VF task performance was significantly smaller in the PD group ON medication than in healthy volunteers across semantic and phonemic VF. No significant group-difference emerged between controls and the PD group in the OFF condition. The comparison between both treatment conditions within the PD group did not reach statistical significance. The observed pattern of results indicates a faster decay of semantic network activation during lexical access in PD patients on dopaminergic medication. In view of improved word generation, this finding is consistent with a concept of more focused neural activity by an increased signal-to-noise ratio due to dopaminergic neuromodulation. However, the effect of dopaminergic stimulation on VF output suggests a trade-off between these beneficial effects and increased error-rates.

The loci of Stroop effects: a critical review of methods and evidence for levels of processing contributing to color-word Stroop effects and the implications for the loci of attentional selection

Despite instructions to ignore the irrelevant word in the Stroop task, it robustly influences the time it takes to identify the color, leading to performance decrements (interference) or enhancements (facilitation). The present review addresses two questions: (1) What levels of processing contribute to Stroop effects; and (2) Where does attentional selection occur? The methods that are used in the Stroop literature to measure the candidate varieties of interference and facilitation are critically evaluated and the processing levels that contribute to Stroop effects are discussed. It is concluded that the literature does not provide clear evidence for a distinction between conflicting and facilitating representations at phonological, semantic and response levels (together referred to as informational conflict), because the methods do not currently permit their isolated measurement. In contrast, it is argued that the evidence for task conflict as being distinct from informational conflict is strong and, thus, that there are at least two loci of attentional selection in the Stroop task. Evidence suggests that task conflict occurs earlier, has a different developmental trajectory and is independently controlled which supports the notion of a separate mechanism of attentional selection. The modifying effects of response modes and evidence for Stroop effects at the level of response execution are also discussed. It is argued that multiple studies claiming to have distinguished response and semantic conflict have not done so unambiguously and that models of Stroop task performance need to be modified to more effectively account for the loci of Stroop effects.

Objective ages of acquisition for 3300+ simplified Chinese characters

We report the construction of two age-of-acquisition (AoA) norms for 3300+ characters in simplified Chinese, which make up about 99% of the texts used in daily life. We determined a character's AoA according to the time in which the character is formally learned in two sets of leading textbooks of Chinese in compulsory education, published respectively on the basis of the 2001 and 2011 national curriculum. Apart from having a significantly larger coverage of characters than previous norms, the current norms also outperformed them in explaining accuracy and reaction times in four large-scale databases for character decision, character naming, or character handwriting, even after controlling for the effects of frequency, number of meanings, and number of strokes. The explanatory advantage of the current norms suggests that, compared to earlier norms, the current norms capture more up-to-date character AoAs; these findings also highlight the diachronic nature of some lexical variables such as AoA and frequency. The developed objective AoA norms can be used for subsequent research on Chinese character recognition or production.

Using Verb Extension to Gauge Children's Verb Meaning Construals: The Case of Chinese

Verb extension is a crucial gauge of the acquisition of verb meaning. In English, studies suggest that young children show conservative extension. An important test of whether an early conservative extension is a general phenomenon or a function of the input language is made possible by Chinese, a language in which verbs are more frequent and acquired earlier. This study tested whether 3-year-old Chinese children extended a group of familiar verbs that specify various ways to carry objects. Shown videos that portrayed typical, mid-typical, or atypical carrying actions (as verified by Chinese adults), children were asked to judge whether they were examples of specific Chinese carry verbs. Children’s verb extensions were mostly limited to typical exemplars, suggesting that an early conservative extension may be universal. Furthermore, extension breadth was related to the onset of verb production: verbs acquired earlier elicited more extension judgments than those acquired later.

Word Frequency Is Associated With Cognitive Effort During Verbal Working Memory: A Functional Near Infrared Spectroscopy (fNIRS) Study

PURPOSE

Psycholinguistic models traditionally view verbal working memory capacity as independent from linguistic features; connectionist models suggest otherwise. Moreover, lexical processing studies show high frequency words differ in cognitive effort from low frequency words, although these effects during concurrent processing of words in working memory are unknown. This novel study examines potential differences in cognitive effort, as measured by differences in HbO2 and Hb, for high frequency versus low frequency words during a working memory paradigm.

METHODS

A total of 21 neurologically typical participants (age 18-23) completed an auditory, n-back, working memory task comparing performance with high- as compared to low- frequency words. Hemodynamic changes in the prefrontal cortex were recorded with a continuous-wave functional near-infrared spectroscopy (fNIRS) device. Behavioral data (accuracy, reaction time) were recorded using E-prime.

RESULTS

Differences in word frequency were evident at both behavioral and neurological levels. Participants were more accurate, albeit slower in identifying the target two back in a sequence for low- as compared to high-frequency words. Patterns of hemodynamic changes were also significantly different between HF and LF conditions.

CONCLUSION

The results from this study indicate that the behavioral and neurological signatures inherent in holding high- versus low-frequency words in working memory differs significantly. Specifically, the findings from this study indicated that words differing in frequency place different demands on cognitive processing load in memory updating tasks.

Semantic and lexical features of words dissimilarly affected by non-fluent, logopenic, and semantic primary progressive aphasia

OBJECTIVE

To determine the effect of three psycholinguistic variables-lexical frequency, age of acquisition (AoA), and neighborhood density (ND)-on lexical-semantic processing in individuals with non-fluent (nfvPPA), logopenic (lvPPA), and semantic primary progressive aphasia (svPPA). Identifying the scope and independence of these features can provide valuable information about the organization of words in our mind and brain.

METHOD

We administered a lexical decision task-with words carefully selected to permit distinguishing lexical frequency, AoA, and orthographic ND effects-to 41 individuals with PPA (13 nfvPPA, 14 lvPPA, 14 svPPA) and 25 controls.

RESULTS

Of the psycholinguistic variables studied, lexical frequency had the largest influence on lexical-semantic processing, but AoA and ND also played an independent role. The results reflect a brain-language relationship with different proportional effects of frequency, AoA, and ND in the PPA variants, in a pattern that is consistent with the organization of the mental lexicon. Individuals with nfvPPA and lvPPA experienced an ND effect consistent with the role of inferior frontal and temporoparietal regions in lexical analysis and word form processing. By contrast, individuals with svPPA experienced an AoA effect consistent with the role of the anterior temporal lobe in semantic processing.

CONCLUSIONS

The findings are in line with a hierarchical mental lexicon structure with a conceptual (semantic) and a lexeme (word-form) level, such that a selective deficit at one of these levels of the mental lexicon manifests differently in lexical-semantic processing performance, consistent with the affected language-specific brain region in each PPA variant.

Razak R, Treffers-Daller J, Yap NT, Abboud L, Talebi A, Gureghian M, Tuller L, Haman E. Age of acquisition of 299 words in seven languages: American English, Czech, Gaelic, Lebanese Arabic, Malay, Persian and Western Armenian

We present a new set of subjective Age of Acquisition (AoA) ratings for 299 words (158 nouns, 141 verbs) in seven languages from various language families and cultural settings: American English, Czech, Scottish Gaelic, Lebanese Arabic, Malaysian Malay, Persian, and Western Armenian. The ratings were collected from a total of 173 participants and were highly reliable in each language. We applied the same method of data collection as used in a previous study on 25 languages which allowed us to create a database of fully comparable AoA ratings of 299 words in 32 languages. We found that in the seven languages not included in the previous study, the words are estimated to be acquired at roughly the same age as in the previously reported languages, i.e. mostly between the ages of 1 and 7 years. We also found that the order of word acquisition is moderately to highly correlated across all 32 languages, which extends our previous conclusion that early words are acquired in similar order across a wide range of languages and cultures.

Linguistic and Perceptual Mapping in Spatial Representations: An Attentional Account

Building on evidence for embodied representations, we investigated whether Spanish spatial terms map onto the NEAR/FAR perceptual division of space. Using a long horizontal display, we measured congruency effects during the processing of spatial terms presented in NEAR or FAR space. Across three experiments, we manipulated the task demands in order to investigate the role of endogenous attention in linguistic and perceptual space mapping. We predicted congruency effects only when spatial properties were relevant for the task (reaching estimation task, Experiment 1) but not when attention was allocated to other features (lexical decision, Experiment 2; and color, Experiment 3). Results showed faster responses for words presented in Near-space in all experiments. Consistent with our hypothesis, congruency effects were observed only when a reaching estimate was requested. Our results add important evidence for the role of top-down processing in congruency effects from embodied representations of spatial terms.

Ratings of age of acquisition of 299 words across 25 languages: Is there a cross-linguistic order of words?

We present a new set of subjective age-of-acquisition (AoA) ratings for 299 words (158 nouns, 141 verbs) in 25 languages from five language families (Afro-Asiatic: Semitic languages; Altaic: one Turkic language: Indo-European: Baltic, Celtic, Germanic, Hellenic, Slavic, and Romance languages; Niger-Congo: one Bantu language; Uralic: Finnic and Ugric languages). Adult native speakers reported the age at which they had learned each word. We present a comparison of the AoA ratings across all languages by contrasting them in pairs. This comparison shows a consistency in the orders of ratings across the 25 languages. The data were then analyzed (1) to ascertain how the demographic characteristics of the participants influenced AoA estimations and (2) to assess differences caused by the exact form of the target question (when did you learn vs. when do children learn this word); (3) to compare the ratings obtained in our study to those of previous studies; and (4) to assess the validity of our study by comparison with quasi-objective AoA norms derived from the MacArthur-Bates Communicative Development Inventories (MB-CDI). All 299 words were judged as being acquired early (mostly before the age of 6 years). AoA ratings were associated with the raters' social or language status, but not with the raters' age or education. Parents reported words as being learned earlier, and bilinguals reported learning them later. Estimations of the age at which children learn the words revealed significantly lower ratings of AoA. Finally, comparisons with previous AoA and MB-CDI norms support the validity of the present estimations. Our AoA ratings are available for research or other purposes.

Human Brain Mapping of Visual Script Familiarity between Phonological and Logographic Language: 3 T Functional MRI Study

Neurolinguistic circuitry for two different scripts of language, such as phonological scripts (PhonoS) versus logographic scripts (LogoS) (e.g., English versus Chinese, resp.), recruits segregated neural pathways according to orthographic regularity (OrthoR). The purpose of this study was to identify the effect of VSF for cortical representation according to different OrthoR to represent Hangul versus Hanja as PhonoS versus LogoS, respectively. A total of 24 right-handed, native Korean undergraduate students with the first language of PhonoS and the second language of LogoS were divided into high- or low-competent groups for L2 of LogoS. The implicit word reading task was performed using Hanja and Hangul scripts during functional magnetic resonance imaging (fMRI) acquisition. Fluctuations of fMRI BOLD signal demonstrated that the LogoS was associated with the ventral pathway, whereas PhonoS was associated with the dorsal pathway. By interaction analysis, compared with high-competent group, low-competent group showed significantly greater activation for Hanja than for Hangul reading in the right superior parietal lobule area and the left supplementary motor area, which might be due to neural efficiency such as attention and cognition rather than core neurolinguistic neural demand like OrthoR processing.

Not all identification tasks are born equal: testing the involvement of production processes in perceptual identification and lexical decision

The distinction between identification and production processes suggests that implicit memory should require more attention resources when there is a competition between alternative solutions during the test phase. The present two experiments assessed this hypothesis by examining the effects of divided attention (DA) at encoding on the high- and low-response-competition versions of perceptual identification (Experiment 1) and lexical decision (Experiment 2). In both experiments, words presented in the high-response-competition condition had many orthographic neighbours and at least one higher-frequency neighbour, whereas words presented in the low-response-competition condition had few orthographic neighbours and no higher-frequency neighbour. Consistent with the predictions of the identification/production distinction, Experiment 1 showed that DA reduced repetition priming in the high-, but not in the low-response-competition version of perceptual identification; in contrast, DA had comparable effects in the two versions of lexical decision (Experiments 2). These findings provide the first experimental evidence in support of the hypothesis that perceptual identification, a task nominally based on identification processes, might involve a substantive production component.

Mental Reactivation and Pleasantness Judgment of Experience Related to Vision, Hearing, Skin Sensations, Taste and Olfaction

Language acquisition is based on our knowledge about the world and forms through multiple sensory-motor interactions with the environment. We link the properties of individual experience formed at different stages of ontogeny with the phased development of sensory modalities and with the acquisition of words describing the appropriate forms of sensitivity. To test whether early-formed experience related to skin sensations, olfaction and taste differs from later-formed experience related to vision and hearing, we asked Russian-speaking participants to categorize or to assess the pleasantness of experience mentally reactivated by sense-related adjectives found in common dictionaries. It was found that categorizing adjectives in relation to vision, hearing and skin sensations took longer than categorizing adjectives in relation to olfaction and taste. In addition, experience described by adjectives predominantly related to vision, hearing and skin sensations took more time for the pleasantness judgment and generated less intense emotions than that described by adjectives predominantly related to olfaction and taste. Interestingly the dynamics of skin resistance corresponded to the intensity and pleasantness of reported emotions. We also found that sense-related experience described by early-acquired adjectives took less time for the pleasantness judgment and generated more intense and more positive emotions than that described by later-acquired adjectives. Correlations were found between the time of the pleasantness judgment of experience, intensity and pleasantness of reported emotions, age of acquisition, frequency, imageability and length of sense-related adjectives. All in all these findings support the hypothesis that early-formed experience is less differentiated than later-formed experience.

Reading in Spanish and Italian: Effects of Age of Acquisition in Transparent Orthographies?

Despite the similar transparency of their orthographies, reading in Italian has been found to be affected by frequency but not age of acquisition (AoA) [Barca, L., Burani, C., & Arduino, L. S. (2002). Word naming times and psycholinguistic norms for Italian nouns. Behaviour Research Methods, Instruments and Computers, 34, 424–434] while reading in Spanish is affected by AoA but not frequency [Cuetos, F., & Barbón, A. (2006). Word naming in Spanish. European Journal of Cognitive Psychology, 18, 415–436]. We examined this cross-linguistic difference, firstly, through a reanalysis of the Italian and Spanish reading latencies. After eliminating several between-experiment differences, we replicated the AoA effect in Spanish but not in Italian and the frequency effect in Italian but not in Spanish. The cross-linguistic comparison could not equate stimulus imageability; therefore, secondly, we compared the Italian reading latencies with new Spanish reading latencies for imageability-matched words. We found frequency effects but neither an AoA effect nor a language by AoA interaction. We argue that the previously reported cross-linguistic difference in the AoA effect resulted from a between-study difference in stimulus imageability. More imageable words induced more semantic involvement in reading, yielding an AoA effect in Spanish.

Emotion and language: valence and arousal affect word recognition

Emotion influences most aspects of cognition and behavior, but emotional factors are conspicuously absent from current models of word recognition. The influence of emotion on word recognition has mostly been reported in prior studies on the automatic vigilance for negative stimuli, but the precise nature of this relationship is unclear. Various models of automatic vigilance have claimed that the effect of valence on response times is categorical, an inverted U, or interactive with arousal. In the present study, we used a sample of 12,658 words and included many lexical and semantic control factors to determine the precise nature of the effects of arousal and valence on word recognition. Converging empirical patterns observed in word-level and trial-level data from lexical decision and naming indicate that valence and arousal exert independent monotonic effects: Negative words are recognized more slowly than positive words, and arousing words are recognized more slowly than calming words. Valence explained about 2% of the variance in word recognition latencies, whereas the effect of arousal was smaller. Valence and arousal do not interact, but both interact with word frequency, such that valence and arousal exert larger effects among low-frequency words than among high-frequency words. These results necessitate a new model of affective word processing whereby the degree of negativity monotonically and independently predicts the speed of responding. This research also demonstrates that incorporating emotional factors, especially valence, improves the performance of models of word recognition.

Objective age of acquisition norms for a set of 286 words in Russian: relationships with other psycholinguistic variables

Normative data on the objective age of acquisition (AoA) for 286 Russian words are presented in this article. In addition, correlations between the objective AoA and subjective ratings, name agreement, picture name agreement, imageability, familiarity, word frequency, and word length are provided, as are correlations between the objective AoA and two measures of exemplar dominance (exemplar generation frequency and the number of times an exemplar was named first). The correlations between the aforementioned variables are generally consistent with the correlations reported in other normative studies. The objective AoA data are highly correlated with the subjective AoA ratings, whereas the correlations between the objective AoA and other psycholinguistic variables are moderate. The correlations between the objective AoA of Russian words and similar data for other languages are moderately high. The complete word norms may be downloaded from supplementary material.

Does frequency trajectory influence word identification? A cross-task comparison

In a series of six experiments, the influence of frequency trajectory in visual word recognition was investigated. In Experiment 1, frequency trajectory was found to exert a strong and reliable influence on age of acquisition (AoA) ratings. In word reading (Experiment 2), lexical decision (Experiments 3 and 6), proper name decision (Experiment 4), progressive demasking (Experiment 5), and a multiple regression analysis of lexical decision times taken from the French Lexicon Project, the effect of frequency trajectory was not reliable. In contrast, in all the experiments and in the multiple regression analysis, cumulative frequency had a strong and reliable influence on word recognition times. The findings firmly establish that in alphabetic languages such as French, age-limited learning effects do not surface readily in word recognition. In contrast, the total exposure to words across the lifetime is a strong determinant of word recognition speed. The implications of the findings are discussed.

Interactive Effects of Age-of-Acquisition and Repetition Priming in the Lexical Decision Task

The analysis of the interaction between repetition priming and age of acquisition may be used to shed further light on the question of which stages of elaboration are affected by this psycholinguistic variable. In the present study we applied this method in the context of two versions of a lexical decision task that differed in the type of non-words employed at test. When the non-words were illegal and unpronounceable, repetition priming was primarily based on the analysis of orthographic information, while phonological processes were additionally recruited only when using legal pronounceable non-words. The results showed a significant interaction between repetition priming and age of acquisition in both conditions, with priming being greater for late- than for early-acquired words. These findings support a multiple-loci account, indicating that age of acquisition influences implicit memory by facilitating the retrieval of both the orthographic and the phonological representations of studied words.

Imageability and age of acquisition effects in disyllabic word recognition

Imageability and age of acquisition (AoA) effects, as well as key interactions between these variables and frequency and consistency, were examined via multiple regression analyses for 1,936 disyllabic words, using reaction time and accuracy measures from the English Lexicon Project. Both imageability and AoA accounted for unique variance in lexical decision and naming reaction time performance. In addition, across both tasks, AoA and imageability effects were larger for low-frequency words than high-frequency words, and imageability effects were larger for later acquired than earlier acquired words. In reading aloud, consistency effects in reaction time were larger for later acquired words than earlier acquired words, but consistency did not interact with imageability in the reaction time analysis. These results provide further evidence that multisyllabic word recognition is similar to monosyllabic word recognition and indicate that AoA and imageability are valid predictors of word recognition performance. In addition, the results indicate that meaning exerts a larger influence in the reading aloud of multisyllabic words than monosyllabic words. Finally, parallel-distributed-processing approaches provide a useful theoretical framework to explain the main effects and interactions.

Effects of Age-of-Acquisition in the Word-Fragment Completion Task

Barry, Hirsh, Johnston, and Williams (2001) found that Age-of-Acquisition (AoA) interacted with repetition priming in the picture naming task (greater priming for late- than for early-acquired words), and proposed that AoA might affect the stage of access to lexical-phonological representations. The present experiment examined the possibility that AoA may influence the retrieval of visual-orthographic information, by studying its effects in the Word-Fragment Completion Task (WFCT). Results showed that the overall percentages of correct completion were greater for early- than for late-acquired words, while repetition priming was higher for late- than for early-acquired items. Furthermore, the interaction between AoA and WFCT priming remained significant even when the fragments were exposed for only 4 s, reducing possible contributions from phonological and semantic processes. These findings suggest that AoA can affect implicit memory by facilitating the retrieval of the orthographic properties of the studied words.

Age of word acquisition effects in treatment of children with phonological delays

The effects of the age of acquisition (AoA) of words were examined in the clinical treatment of 10 preschool children with phonological delays. Using a single-subject multiple-baseline experimental design, children were enrolled in one of four conditions that varied the AoA of the treated words (early vs. late acquired) relative to their corresponding word frequency (high vs. low frequency). Phonological generalization to treated and untreated sounds in error served as the dependent variable. Results showed that late acquired words induced greater generalization, with an effect size four times greater than early acquired words, whereas the effects of word frequency were minimized. Results are discussed relative to hypotheses about the role of AoA in language acquisition and the relevance of this variable for phonological learning.

Descriptive norms for 245 Italian idiomatic expressions

The present study reports descriptive normative measures for 245 Italian verbal idiomatic expressions. For each of the idiomatic expressions the following variables are reported: Length, Knowledge, Familiarity, Age of Acquisition, Predictability, Syntactic flexibility, Literality and Compositionality. Syntactic flexibility was assessed using five syntactic operations: adverb insertion, adjective insertion, left dislocation, passive and movement. The psycholinguistic relevance of each dimension, their measures and the correlations among them are provided and discussed. The databases are freely available for down-loading from the Psychonomic Society Web archive at www.psychonomic.org/archive/.

Age of acquisition effects in reading Chinese: Evidence in favour of the arbitrary mapping hypothesis

Two experiments explored the locus of the age of acquisition (AoA) effects in the processing of Chinese characters and tested the arbitrary mapping hypothesis of AoA effects. In Experiment 1, AoA and predictability from orthography to pronunciation of Chinese characters were manipulated in a naming task. Results showed a larger AoA effect for characters from low-predictive families than for characters from high-predictive families. In Experiment 2, AoA and predictability from orthography to meaning were manipulated in a semantic category judgment task. Results showed a larger AoA effect for characters from low-predictive families than for characters from high-predictive families. In summary, the two experiments provided empirical support for the arbitrary mapping hypothesis to explain AoA effects.

Age of Acquisition, Word Frequency, and Picture–Word Interference

In two experiments participants named pictures superimposed with unrelated words. The age of acquisition (AoA) of the picture names was manipulated. Additionally, the word frequency (WF, Experiment 1) or AoA (Experiment 2) of the interfering distractor words was manipulated. Early-acquired pictures were named faster than their late-acquired counterparts. Both WF and AoA modulated the degree of interference from the irrelevant word; low-frequency and late-acquired words produced most interference. In neither case did the WF or AoA of the distractor word interact with the AoA of the picture. The results show that in the context of word processing both WF and AoA have similar effects.

The varying effects of age of acquisition

There are a number of theories that suggest that age of acquisition (AoA) effects are not uniform across different tasks. Catling and Johnston (2006a) found greater AoA effects within an object-naming task than in a semantic classification task. They explained these findings by suggesting that AoA effects might accumulate according to how many levels of representation a task necessitates access to. Brysbaert and Ghyselinck (2006) explain the difference in AoA effects by proposing two distinct types of AoA (frequency dependent and frequency independent), the first accounted for by a connectionist-type mechanism and the latter situated at the interface between semantics and word production. Moreover, Moore, Smith-Spark, and Valentine (2004) and Holmes and Ellis (2006) have suggested that there are two loci of AoA effects: at the phonological level and somewhere within the perceptual level of representation. Again, this could account for the varying degrees of AoA effects. This study sets about testing these ideas by assessing the effect size of AoA across a series of different tasks that necessitate access to various levels of representation. Experiments 1–4 demonstrate significant effects of AoA in a novel picture–picture verification task, an object classification task, a picture verification task, and an object-naming task. Experiment 5 showed no effects of initial phoneme on the naming of the critical objects used within Experiments 1–4. The implication of the varying AoA effect sizes found within Experiments 1–4 in relation to explanations of AoA are discussed.

The many places of frequency: evidence for a novel locus of the lexical frequency effect in word production

The effect of lexical frequency on language-processing tasks is exceptionally reliable. For example, pictures with higher frequency names are named faster and more accurately than those with lower frequency names. Experiments with normal participants and patients strongly suggest that this production effect arises at the level of lexical access. Further work has suggested that within lexical access this effect arises at the level of lexical representations. Here we present patient E.C. who shows an effect of lexical frequency on his nonword error rate. The best explanation of his performance is that there is an additional locus of frequency at the interface of lexical and segmental representational levels. We confirm this hypothesis by showing that only computational models with frequency at this new locus can produce a similar error pattern to that of patient E.C. Finally, in an analysis of a large group of Italian patients, we show that there exist patients who replicate E.C.'s pattern of results and others who show the complementary pattern of frequency effects on semantic error rates. Our results combined with previous findings suggest that frequency plays a role throughout the process of lexical access.

Estimating when and how words are acquired: a natural experiment on the development of the mental lexicon

PURPOSE

Sensitivity of subjective estimates of age of acquisition (AOA) and acquisition channel (AC; printed, spoken, signed) to differences in word exposure within and between populations that differ dramatically in perceptual experience was examined.

METHODS

Fifty participants with early-onset deafness and 50 participants with normal hearing rated 175 words in terms of subjective AOA and AC. Additional data were collected using a standardized test of reading and vocabulary.

RESULTS

Participants with early-onset deafness rated words as learned later (M = 10 years) than did participants with normal hearing (M = 8.5 years), F(1, 99) = 28.59, p < .01. Group-averaged item ratings of AOA were highly correlated across the groups (r = .971) and with normative order of acquisition (deaf: r = .950, hearing: r = .946). The groups differed in their ratings of AC (hearing: printed = 30%, spoken = 70%, signed = 0%; deaf: printed = 45%, spoken = 38%, signed = 17%).

CONCLUSIONS

Subjective AOA and AC measures are sensitive to between- and within-group differences in word experience. The results demonstrate that these subjective measures can be applied as proxies for direct measures of lexical development in studies of lexical knowledge in adults with prelingual onset deafness.

Age of acquisition and repetition priming effects on picture naming of children who do and do not stutter

The effects of age of acquisition and repetition priming on picture naming latencies and errors were studied in 22 children who stutter (CWS) and 22 children who do not stutter (CWNS) between the ages of 3;1 and 5;7. Children participated in a computerized picture naming task where they named pictures of both early and late acquired (AoA) words in two consecutive stages. Findings revealed that all children's picture naming latencies and errors were reduced following repetition priming and in response to early AoA words relative to late AoA words. AoA and repetition priming effects were similar for children in both talker groups, with one exception. Namely, CWS benefitted significantly more, in terms of error reduction, than CWNS from repetition priming for late AoA words. In addition, CWNS exhibited a significant, positive association between linguistic speed and measures of vocabulary, but CWS did not. These findings were taken to suggest that the (a) semantic-phonological connections of CWS may not be as strong as those of CWNS, and (b) existing lexical measures may not be sensitive enough to differentiate CWS from CWNS in lexically related aspects of language production.

EDUCATIONAL OBJECTIVES

After reading this article, the learner will be able to: (a) describe the effects of repetition priming and age of word acquisition in speech production; (b) summarize the performance similarities and differences of children who stutter and children who do not stutter on a computerized picture naming task; and (c) compare the results of the present study with previous work in this area.

Objective age of acquisition norms for a set of 328 words in Spanish

Age of acquisition is one of the most important variables in picture naming. For this reason, a large number of findings concerning age-of-acquisition data have been published in recent years in a number of different languages. In this article, objective age-of-acquisition data in Spanish for 328 pictures were collected from a pool of 760 children, half of whom were boys and the other half girls. A total of 246 pictures were selected from the Snodgrass and Vanderwart (1980) set, and 82 were new pictures. Like the results of other studies, we found that objective age of acquisition correlates less than rated age of acquisition with familiarity and frequency, which indicates that the objective measure is less contaminated by other variables than are rated estimates. A very high correlation was obtained between the norms from this study and those published in English, French, Icelandic, and Italian. These norms will be very useful to Spanish psycholinguists and clinicians. Related materials may be downloaded from the Psychonomic Society Web archive at www.psychonomic.org/archive/.

Age-of-acquisition differences in young and older adults affect latencies in lexical decision and semantic categorization

An ongoing discussion about the role of age of acquisition (AoA) in word processing concerns the confound with word frequency. This study removed possible frequency confounds by comparing AoA and word familiarity differences in young (18-23 years) and older (52-56 years) adults. A first study investigated the differences in AoA and word familiarity ratings. The norms of AoA and familiarity were significantly different for young and older adults whereas these were previously considered equivalent [Morrison, C. M., Hirsh, K. W., Chappell, T., & Ellis, A. W. (2002). Age and age of acquisition: An evaluation of the cumulative frequency hypothesis. European Journal of Cognitive Psychology, 14, 435-459]. In the second study, AoA and familiarity effects were significantly different for the older and young adults in a lexical decision task. The third study replicated these findings in a semantic artifact/naturally occurring categorization experiment, thus providing further evidence for AoA-effects when word processing requires semantic mediation. Results from both studies were in line with the hypothesis that AoA effects on word processing cannot be accounted for by word frequency or other possible confounds.

Predictors of naming decline after dominant temporal lobectomy: age at onset of epilepsy and age of word acquisition

This study examined factors affecting object naming decline in patients who have undergone anterior temporal lobectomy (ATL) and the correlation between age of word acquisition and loss of specific object names postoperatively. The Boston Naming Test (BNT) was used to assess changes in object-naming performance in patients who underwent ATL. Correlation analyses were performed by group (dominant or nondominant ATL) on individual items from the BNT to determine if age of acquisition of object names had an effect on postoperative word loss. The influence of age at onset of seizures on naming decline was examined in the dominant ATL group. Only patients who had undergone dominant ATL experienced significant clinical and statistical declines after surgery. Among the patients who underwent dominant ATL, those with late age at onset of seizures declined significantly more than those with early-onset seizures. When individual object names were examined, age of acquisition of words predicted whether words were lost or gained after surgery.

Traces of vocabulary acquisition in the brain: Evidence from covert object naming

One of the strongest predictors of the speed with which adults can name a pictured object is the age at which the object and its name are first learned. Age of acquisition also predicts the retention or loss of individual words following brain damage in conditions like aphasia and Alzheimer's disease. Functional Magnetic Resonance Imaging (fMRI) was used to reveal brain areas differentially involved in naming objects with early or late acquired names. A baseline task involved passive viewing of non-objects. The comparison between the silent object naming conditions (early and late) with baseline showed significant activation in frontal, parietal and mediotemporal regions bilaterally and in the lingual and fusiform gyri on the left. Direct comparison of early and late items identified clusters with significantly greater activation for early acquired items at the occipital poles (in the posterior parts of the middle occipital gyri) and at the left temporal pole. In contrast, the left middle occipital and fusiform gyri showed significantly greater activation for late than early acquired items. We propose that greater activation to early than late objects at the occipital poles and at the left temporal pole reflects the more detailed visual and semantic representations of early than late acquired items. We propose that greater activation to late than early objects in the left middle occipital and fusiform gyri occurs because those areas are involved in mapping visual onto semantic representations, which is more difficult, and demands more resource, for late than for early items.