Word Recognition Reaction Time Research Articles

The graded effect of valence on word recognition in Spanish.

The influence of emotional content on language processing remains unclear. Previous research conducted in English has obtained contradictory results regarding the effects of valence on word recognition. Whereas some studies indicate that valence predicts recognition latencies such that negative words are processed more slowly than positive words, other studies indicate facilitation of responses to emotional (both positive and negative) compared to neutral words. The authors examined the influence of valence and arousal on word recognition reaction time (RT) using large-scale word naming and lexical decision data-sets in Spanish. They found that linear mixed-effects model estimates revealed a valence but not an arousal effect on reading latencies. The influence of valence was better captured by a graded (RTs to positive words < neutral < negative) than by a categorical (positive < negative) valence effect. A categorical emotional versus neutral effect was not reliably observed. In an advance on previous research, the authors' analyses showed that the valence effect is substantially more prominent in lexical decision than in pronunciation. These results mirror some of those reported previously in English, adding evidence to support their validity, and demonstrating important parallels in word recognition processes in orthographically shallow as well as deep languages. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Role of auditory attention in the real‐time processing of simple grammar by children with specific language impairment: a preliminary investigation

This study investigates the effects of two dimensions of attentional functioning, sustained focus of attention and resource capacity/allocation, on the real-time processing of simple sentences by children with specific language impairment (SLI) and typically developing (TD) children matched for age. Thirty-six school-age children with SLI and 36 age-matched TD peers completed an auditory continuous performance task (ACPT) as a measure of sustained attention, a concurrent verbal processing-storage task as a measure of resource capacity/allocation, and a word-recognition reaction time (RT) task (index of sentence processing). Correlation and regression analyses were run to determine the association between the two measures of attention and word recognition RT. Children with SLI were outperformed by the TD children on each of the tasks. For each group, scores on both the ACPT and concurrent processing-storage tasks significantly correlated with word recognition RT. The partial correlations (with the effects of age removed) remained significant, but only for the SLI group. Results of a regression analysis for the SLI group showed that age predicted 12.3% of unique variance in word recognition RT, while ACPT score accounted for an additional significant 45.7% of unique variance and the processing-storage task score accounted for another significant 4.3% of unique variance. The real-time processing of simple grammar by children with SLI appears to involve significant use of sustained focus of attention and attentional resource capacity. In the case of TD children, however, neither sustained attention nor attentional resources appears to be significantly involved in simple sentence processing.

The effects of l-theanine, caffeine and their combination on cognition and mood

l-Theanine is an amino acid found naturally in tea. Despite the common consumption of l-theanine, predominantly in combination with caffeine in the form of tea, only one study to date has examined the cognitive effects of this substance alone, and none have examined its effects when combined with caffeine. The present randomised, placebo-controlled, double-blind, balanced crossover study investigated the acute cognitive and mood effects of l-theanine (250 mg), and caffeine (150 mg), in isolation and in combination. Salivary caffeine levels were co-monitored. l-Theanine increased ‘headache’ ratings and decreased correct serial seven subtractions. Caffeine led to faster digit vigilance reaction time, improved Rapid Visual Information Processing (RVIP) accuracy and attenuated increases in self-reported ‘mental fatigue’. In addition to improving RVIP accuracy and ‘mental fatigue’ ratings, the combination also led to faster simple reaction time, faster numeric working memory reaction time and improved sentence verification accuracy. ‘Headache’ and ‘tired’ ratings were reduced and ‘alert’ ratings increased. There was also a significant positive caffeine × l-theanine interaction on delayed word recognition reaction time. These results suggest that beverages containing l-theanine and caffeine may have a different pharmacological profile to those containing caffeine alone.

Examining the Language Performances of Children With and Without Specific Language Impairment: Contributions of Phonological Short-Term Memory and Speed of Processing

This study investigated the effects of processing speed and phonological short-term memory (PSTM) on children's language performance. Forty-eight school-age children with specific language impairment (SLI) and age peers completed auditory detection reaction time (RT) and nonword repetition tasks, the Clinical Evaluation of Language Fundamentals-Revised (CELF-R; E. Semel, E. Wiig, & W. Secord, 1987), and a word recognition RT task. Correlation and regression were used to determine unique and shared contributions to variance among measures. Children with SLI were outperformed by age peers on each task. Auditory detection RT was correlated with nonword repetition (NWR) in each group. However, both variables covaried with age, and auditory detection RT did not contribute unique variance to NWR in either group. For the SLI group, NWR predicted unique variance in CELF-R performance (about 15%); auditory detection RT predicted a smaller amount of unique variance in the word recognition RT task (about 9%). Processing speed and PSTM measures covaried with chronological age. Processing speed was associated with offline language performance only through association with PSTM. Processing speed contributed to online language performance, suggesting that speed is associated with processing more familiar language material (i.e., lexical content and structure) than less familiar material (e.g., various content on the CELF-R).

Speed of lexical decision correlates with diffusion anisotropy in left parietal and frontal white matter: Evidence from diffusion tensor imaging

Speed of visual word recognition is an important variable affecting linguistic competence. Although speed of visual word recognition varies widely between individuals, the neural basis of reaction time (RT) differences is poorly understood. Recently, a magnetic resonance technique called diffusion tensor imaging (DTI) has been shown to provide information about white matter (WM) microstructure in vivo. Here, we used DTI to explore whether visual word recognition RT correlates with regional fractional anisotropy (FA) values in the WM of healthy young adults. Participants completed a speeded lexical decision task that involved visual input, linguistic processes, and a motor response output. Results indicated that lexical decision RT was correlated negatively with FA in WM of inferior parietal and frontal language regions rather than in WM of visual or motor regions. Voxels within the inferior parietal and frontal correlation clusters were composed primarily of DTI-based tracts oriented in the anterior–posterior orientation at or near the superior longitudinal fasciculus (SLF) and likely including other smaller association fibers. These results provide new microstructural evidence demonstrating that speed of lexical decision is associated with the degree to which portions of frontal and parietal WM are directionally oriented.

Real‐time language processing in school‐age children with specific language impairment

School-age children with specific language impairment (SLI) exhibit slower real-time (i.e. immediate) language processing relative to same-age peers and younger, language-matched peers. Results of the few studies that have been done seem to indicate that the slower language processing of children with SLI is due to inefficient higher-order linguistic processing and not to difficulties with more basic acoustic-phonetic processing. However, this claim requires further experimental verification. It was investigated whether the real-time language processing deficit of children with SLI arises from inferior acoustic-phonetic processing, inefficient linguistic processing, or both poor sensory processing and linguistic processing. If these children's impaired online language processing is due to inferior acoustic-phonetic processing, then their reaction time (RT) for recognizing words presented in list fashion should be significantly longer relative to control children's RT. If, however, their impaired language processing relates to inefficient linguistic processing, then, relative to control children, their RT for word-list-presented words should be comparable and their sentence-embedded word-recognition RT should be significantly longer. Sixteen school-age children with SLI, 16 age-matched (CA) typically developing children, and 16 receptive-syntax matched (RS) children completed two word-recognition RT tasks. In one task, children monitored word lists for the occurrence of a target word (isolated lexical processing task). In the second task, children monitored simple sentences for a target word (sentence-embedded lexical processing task). In both tasks, children made a timed response immediately upon recognizing the target. Children with SLI and CA children showed comparable RT in the isolated lexical processing task and both were faster than RS children. In the sentence-processing task, children with SLI were slower at lexical processing than CA and RS children, with CA children demonstrating the fastest processing. The real-time language processing of children with SLI appears to be attributable to inefficient higher-order linguistic processing operations and not to inferior acoustic-phonetic processing. The slower language processing of children with SLI relative to younger, language-matched children suggests that the language mechanism of children with SLI operates more slowly than what might otherwise be predicted by their linguistic competence.

Effects of input rate and age on the real‐time language processing of children with specific language impairment

School-age children with specific language impairment (SLI) exhibit slower real-time (i.e. immediate) language processing relative to same-age peers. The offline sentence comprehension of children with SLI can be improved when the input is slowed down. Although this finding suggests that a slower input delivery facilitates these children's language processing, such an interpretation is premature, as there are no data directly addressing the issue. Additionally, while typically developing (TD) children demonstrate age-related improvements in language processing (i.e. they become faster processors), it is unclear whether children with SLI show the same developmental improvement. It was investigated whether a reduced input rate can enhance the online language processing of children with SLI. If it does, their reaction time (RT) for recognizing words embedded in sentences delivered at a slow rate should be faster relative to words in normal- and fast-rate sentences. For TD children, RT should be unaffected by rate manipulation, as their language-processing system is sufficiently robust to handle such a simple input manipulation. A secondary aim was to provide preliminary data on the developmental course of language processing proficiency in children with SLI. Twenty school-age children with SLI and 20 age-matched TD children completed a word recognition RT task. Children monitored simple sentences for a target word and made a timed response immediately upon recognizing the target. Sentences were presented at 'normal', 'slow' and 'fast' speaking rates. There was a significant group by input rate interaction. Children with SLI, relative to TD peers, yielded significantly slower RT for normal- and fast-rate sentences, but faster RT for slow-rate sentences. Within-group analyses showed the children with SLI produced the fastest RT for slow-rate sentences and the slowest RT for fast-rate sentences. The TD children showed the opposite response pattern: the fastest RT for fast-rate sentences and the slowest RT for slow-rate sentences. Age also had a significant effect. Regardless of language status, older children produced faster RT than younger children. Interestingly, even the oldest children with SLI still demonstrated significantly slower RT than the youngest TD children. The real-time language processing of children with SLI can be facilitated when the material is presented at a slower rate. A slower rate apparently allows these children time to allocate their attentional resources more effectively to the various processing operations supporting comprehension. Additionally, the language proficiency of children with SLI improves with age. However, older children with SLI are still slower than their youngest TD peers, suggesting that the language-processing apparatus of children with SLI operates even more inefficiently than what their receptive language knowledge might otherwise predict.

Examining the nature of lexical processing in children with specific language impairment: Temporal processing or processing capacity deficit?

The real-time lexical processing of children with specific language impairment (SLI) was examined, and the focus was to determine whether a temporal processing deficit or a general processing capacity deficit disrupts these children's lexical processing. A group of SLI children (mean age 8;3), a group of age-matched children (CA, mean age 8;1), and a group of receptive syntax-matched children (RS; mean age 6;7) completed a sentence processing task in which they monitored sentences for a target word appearing at the beginning, middle, or end of sentences. Sentences systematically varied with respect to containing either a high proportion of stop consonants (stop-loaded sentences) or a high proportion of nonstop consonants (nonstop-loaded sentences). Children also completed the Identification (ID) Speech Perception Task. On the sentence processing task, SLI children yielded significantly slower word recognition reaction time (RT) overall than both CA and RS controls. Sentence type had no effect on any subject group's RT. No Group × Sentence Type interaction was found. On the ID task, SLI children performed significantly worse than CA controls but similarly to RS children. No correlation was found between temporal processing and lexical processing (for either sentence type or sentences combined) for any group. The findings are interpreted to suggest that a general processing capacity limitation was responsible for the poor ID task performance and slower lexical processing of SLI children.

Relation of working memory to off-line and real-time sentence processing in children with specific language impairment

In this study we examined the influence of working memory on the off-line and real-time sentence comprehension/processing of children with specific language impairment (SLI). A total of 12 children with SLI, 12 normally developing children matched for chronological age (CA), and 12 children matched for receptive syntax (RS) completed three tasks. In the working memory task, children recalled as many words as possible under three processing load conditions varying in the number of mental operations (i.e., no load, single load, dual load). In the off-line comprehension task, children listened to linguistically nonredundant and redundant sentences. In the real-time sentence processing task, children monitored sentences for the occurrence of a target word appearing at the beginning, middle, or end of a test sentence and pushed a response pad as quickly as possible upon hearing the target. In the memory task, SLI children recalled fewer words in the dual-load condition relative to CA peers, who showed no condition effect. The SLI and RS groups performed similarly overall; however, both groups recalled fewer words in the dual-load condition than in the other conditions. In the off-line task, the SLI group comprehended fewer sentences of both types relative to the CA controls and fewer redundant sentences relative to themselves and to the RS controls. A significant correlation between working memory and sentence comprehension was found for the SLI group and control groups. For the on-line task, between-group analyses revealed that the SLI group yielded an overall slower word recognition reaction time than the CA and RS groups. Working memory and sentence processing were not correlated for any group. Results were interpreted to suggest that SLI children have a more limited functional working memory capacity than their CA peers. Children with SLI also appear to have greater difficulty managing their working memory resources relative to both age peers and younger children when performing a conventional off-line sentence comprehension task but not a real-time sentence processing task.

Real-time inflectional processing by children with specific language impairment: effects of phonetic substance.

In this study, we examined the processing of low-phonetic-substance inflections (e.g., third-person-singular -s, past-tense -ed) versus a higher-phonetic-substance inflection (e.g., present-progressive -ing) by children with specific language impairment (SLI) in two types of receptive tasks. Twenty-one children with SLI (Age: 8 years;6 months), 21 chronological age matched (CA; Age: 8;7), and 21 receptive syntax matched (RS; Age: 6;8) children participated in a word-recognition reaction time (RT) task and an off-line task requiring grammaticality judgments. On the RT task, the children with SLI demonstrated RT sensitivity only to the presence of a higher-phonetic-substance inflection, unlike the CA and RS controls who displayed sensitivity to both higher-substance and low-substance inflections. On the grammaticality judgment task, the children with SLI performed more poorly than the CA controls only on sentences missing obligatory low-substance inflections (e.g., "Carl already jump over the fence"). The findings are discussed within the framework of the surface account, which predicts that children with SLI should have greater difficulty processing and making grammatical judgments about low-substance inflections compared to higher-substance inflections.

Language-impaired children's real-time comprehension of spoken language

ABSTRACTLanguage-impaired children have been shown to exhibit a variety of post-sentence comprehension deficits. Comprehension, however, may also be assessed as it develops rather than after it has occurred. The present investigation compared the real-time language processing abilities of language-impaired and normal children using a word recognition reaction time paradigm. Children's reaction times across three word positions in three sentence type conditions were measured. Results showed that the language-impaired children used linguistic context to facilitate word recognition, but were slower to do so than their normally developing peers. The results were interpreted to suggest that language-impaired children are less proficient than normal children at using their linguistic knowledge to develop linguistic representations of sentence meaning. An on-line retrieval deficit or deficient connections among processing units (e.g., Rumelhart &amp; McClelland, 1986a, 1986b; Waltz &amp; Pollack, 1985) are suggested as likely sources of the language-impaired children's language processing difficulties.