Single Word Level Research Articles

Action and object naming versus verb and noun retrieval in connected speech: Comparisons in late bilingual Greek–English anomic speakers

Background: Recently, verb–noun processing differences were reported in a group of late bilingual speakers with fluent, anomic aphasia in Greek (L1) as well as in English (L2) (Kambanaros & van Steenbrugge, 2006). The findings revealed that verb production was significantly more impaired than noun production in both languages during picture naming despite preserved comprehension of action and object names. Aims: The aim of this study is to investigate the total number (quantity) and the diversity (quality or different types) of verbs and nouns produced in conversational speech by the same group of bilingual anomic individuals with aphasia and compare the results to (i) those of the non‐brain‐injured control group and (ii) their action and object naming performances at the single word level, to determine if grammatical class impairments are also evident in spontaneous speech. Methods & Procedures: In order to examine the distribution and diversity of verbs and nouns in spontaneous speech, speech samples of 300 words were collected from the bilingual individuals with fluent aphasia and their controls in L1 and in L2 on two separate occasions, 1 week apart. In addition, two subtests from the Greek Object and Action Test (GOAT: Kambanaros, 2003), the object and action naming subtests, were presented on two separate occasions, 1 week apart, to both groups of bilingual participants in L1 and L2 (cf. Kambanaros & van Steenbrugge, 2006). Outcomes & Results: Late bilingual participants with anomia showed no difficulties retrieving verbs in spontaneous speech in L1 or L2 despite a significant verb deficit in both languages on action naming tasks. However the bilingual group had significant difficulties in relation to noun production in spontaneous speech in L1 and L2. Conclusions: Picture naming remains the standard of word retrieval ability in aphasia. However, object and action naming scores can underestimate and/or overestimate word retrieval performance for nouns and verbs in connected speech.

Neural associative memories for the integration of language, vision and action in an autonomous agent

Language understanding is a long-standing problem in computer science. However, the human brain is capable of processing complex languages with seemingly no difficulties. This paper shows a model for language understanding using biologically plausible neural networks composed of associative memories. The model is able to deal with ambiguities on the single word and grammatical level. The language system is embedded into a robot in order to demonstrate the correct semantical understanding of the input sentences by letting the robot perform corresponding actions. For that purpose, a simple neural action planning system has been combined with neural networks for visual object recognition and visual attention control mechanisms.

Quality of Life for Children With Cochlear Implants: Perceived Benefits and Problems and the Perception of Single Words and Emotional Sounds

This study examined children's self-reported quality of life with a cochlear implant as related to children's actual perceptions of speech and the emotional information conveyed by sound. Effects of age at amplification with hearing aids and fitting of cochlear implants on perceived quality of life were also investigated. A self-reported quality of life questionnaire and assessments of speech perception (single words) and emotion identification were administered to a sample of 37 children with cochlear implants who were congenitally deaf, who were 5-14 years of age, and who all used spoken language. The children reported significant improvement in quality of life because of their cochlear implants, and they also reported low levels of concern about typical problems associated with wearing an implant. The children's perceived quality of life did not significantly predict speech perception performance at the single word level. In contrast, increased quality of life predicted better performance on the emotion identification task. Age at first use of amplification predicted perceived quality of life. The findings regarding age reinforce the importance of early detection and intervention for children's positive quality of life with cochlear implants later in childhood.

The Relationship between Form and Function Level Receptive Prosodic Abilities in Autism

Prosody can be conceived as having form (auditory-perceptual characteristics) and function (pragmatic/linguistic meaning). No known studies have examined the relationship between form- and function-level prosodic skills in relation to the effects of stimulus length and/or complexity upon such abilities in autism. Research in this area is both insubstantial and inconclusive. Children with autism and controls completed the receptive tasks of the Profiling Elements of Prosodic Systems in Children (PEPS-C) test, which examines both form- and function-level skills, and a sentence-level task assessing the understanding of intonation. While children with autism were unimpaired in both form and function tasks at the single-word level, they showed significantly poorer performance in the corresponding sentence-level tasks than controls. Implications for future research are discussed.

Time course of semantic processes during sentence comprehension: An fMRI study

The ability to create new meanings from combinations of words is one important function of the language system. We investigated the neural correlates of combinatorial semantic processing using fMRI. During scanning, participants performed a rating task on auditory word or pseudoword strings that differed in the presence of combinatorial and word-level semantic information. Stimuli included normal sentences comprised of thematically related words that could be readily combined to produce a more complex meaning, semantically incongruent sentences in which content words were randomly replaced with other content words, pseudoword sentences, and versions of these three sentence types in which syntactic structure was removed by randomly re-ordering the words. Several regions showed greater BOLD signal for stimuli with words than for those with pseudowords, including the left angular gyrus, left superior temporal sulcus, and left inferior frontal gyrus, suggesting that these areas are involved in semantic access at the single word level. In the angular and inferior frontal gyri these differences emerged early in the course of the hemodynamic response. An effect of combinatorial semantic structure was observed in the left angular gyrus and left lateral temporal lobe, which showed greater activation for normal compared to semantically incongruent sentences. These effects appeared later in the time course of the hemodynamic response, beginning after the entire stimulus had been presented. The data indicate a complex spatiotemporal pattern of activity associated with computation of word and sentence-level semantic information, and suggest a particular role for the left angular gyrus in processing overall sentence meaning.

Intensive dysarthria therapy for older children with cerebral palsy: findings from six cases

Children with cerebral palsy often have speech, language and communication difficulties that affect their access to social and educational activities. Speech and language therapy to improve the intelligibility of the speech of children with cerebral palsy has long been advocated, but there is a dearth of research investigating therapy effectiveness. To begin to explore the possible effectiveness of therapy focussing on speech production, six students aged 10-18 years, were given intensive individual therapy to increase breath support for speech, maintain breath support and volume across utterances and hence maximise their background effort for speech. Intelligibility of single words and connected speech was measured immediately before and after the block of therapy and again seven weeks later. Gains in intelligibility were observed at the single word level, but not for continuous speech. Implications for therapy and future research are discussed.

Accuracy of Repetition of Digitized and Synthesized Speech for Young Children in Background Noise

The present study investigated the intelligibility of digitized and synthesized speech output in background noise for children 3-5 years old. The purpose of the study was to determine whether there was a difference in the intelligibility (ability to repeat) of 3 types of speech output (digitized, DECTalk synthesized, and MacinTalk synthesized) in single words and sentences, presented within and out of context. The dependent variable was speech intelligibility (number of individual words repeated correctly). The study used a mixed-model design. Ninety typically developing children (3-5 years old) were assigned to each of 3 speech type conditions. Participants were asked to repeat 20 words and 10 short sentences. Half of the stimuli were preceded by contextual information (topic cue), and half were presented without any context. Young children have difficulty accurately repeating some digitized and synthesized messages in background noise. Overall, the older children (4- and 5-year-olds) performed better than the 3-year-old children. Increasing information through context or longer messages (i.e., sentences) did facilitate intelligibility overall, although there was a statistically significant Message Length x Context x Speech Type interaction. For 3-5-year-olds, the intelligibility of single words is very low (55%-77%). The intelligibility of sentences is higher, but the sole use of sentences for communication is problematic. Contextual information facilitates intelligibility and is a promising approach for ensuring effective communication. Future research is needed to improve the intelligibility of speech output at the single word level in order to maximize the benefits of speech output.

The processing of lexical stress during visual word recognition: Typicality effects and orthographic correlates

Many studies that have examined reading at the single-word level have been restricted to the processing of monosyllabic stimuli, and, as a result, lexical stress has not been widely investigated. In the experiments reported here, we used disyllabic words and nonwords to investigate the processing of lexical stress during visual word recognition. In Experiments 1 and 2, we found an effect of stress typicality in naming and lexical decision. Typically stressed words (trochaic nouns and iambic verbs) elicited fewer errors than atypically stressed words (iambic nouns and trochaic verbs). In Experiment 3, we carried out an analysis of 340 word endings and found clear orthographic correlates of both grammatical category and lexical stress in word endings. In Experiment 4, we demonstrated that readers are sensitive to these cues in their processing of nonwords during two tasks: sentence construction and stress assignment. We discuss the implications of these findings with regard to psycholinguistic models of single-word reading.

Putney Auditory Single Word Yes/No Assessment (PASWORD). Development of a reliable test of yes/no at a single word level in patients unable to participate in assessments requiring a specific motor response: an exploratory study

There are very few formal language assessments aimed at the very severely neurologically impaired individual. These individuals often have multiple deficits on top of their communication impairment that demand a novel approach to assessment. The authors set out to devise a tool (PASWORD) to enable professionals in this field to screen their clients' ability to understand and respond to very simple, closed questions by using their preferred modality. PASWORD assessment was examined for its reliability as a tool for determining whether profoundly neurologically impaired individuals could indicate yes or no reliably to simple closed questions. The assessment comprises 20 high-frequency objects that can be presented visually, auditorily or in the tactile modality, depending on the subject's abilities. Subjects are then asked a one-word level closed question related to the object and were asked to give a yes or no response. Seventy control subjects with no neurological impairment first underwent the PASWORD test to assess for ambiguities in the test items (group 1, n = 74). Neurologically impaired subjects at the Royal Hospital for Neuro-disability in the two experimental groups were allocated according to the opinion of the experienced multidisciplinary team, which observed the subjects closely over a period of time, in different contexts. Those that the team agreed were reliably able to answer simple yes/no questions on observation (group 2, n = 9) and those the team agreed could not indicate yes/no reliably to closed questions (group 3, n = 7). The results of the PASWORD were then compared with the original opinion of the team. Groups 2 and 3 were studied on two occasions to examine test-retest reliability. There were no real ambiguities in the test items and the results of the PASWORD reflected the opinion of the experienced multidisciplinary team. As there are no other tests of single-word closed questions, which can be presented in any of three modalities and during which the subject can respond in any augmentative or alternative fashion, the opinion of the team at the Royal Hospital, a centre of excellence for neurorehabilitation, was used against which to measure reliability. The findings imply that PASWORD is a useful screening tool when assessing the basic language skills of neurologically impaired individuals, whose extensive physical, linguistic and cognitive deficits often render the administration of more traditional language assessments impossible.

The comprehension of ambiguous idioms in aphasic patients

The ability to understand ambiguous idioms was assessed in 15 aphasic patients with preserved comprehension at a single word level. A string-to-word matching task was used. Patients were requested to choose one among four alternatives: a word associated with the figurative meaning of the idiom string; a word semantically associate with the last constituent of the idiom string; and two unrelated words. The results showed that patients’ performance was impaired with respect to a group of matched controls, with patients showing a frontal and/or temporal lesion being the most impaired. A significant number of semantically associate errors were produced, suggesting an impairment of inhibition mechanisms and/or of recognition/activation of the idiomatic meaning.

Exploring the Processing Continuum of Single-Word Comprehension in Aphasia

This study investigated the vulnerability of lexical processing in individuals with aphasia. Though classical teaching of aphasia syndromes holds that people with Broca's aphasia have intact comprehension at the single-word level, the nature and extent of this purported sparing were explored under suboptimal processing conditions. A combination of acoustic distortions (low-pass filtering and time compression) was used to probe for "break points" in lexical comprehension in a group of individuals with aphasia. Results suggest that accurate and efficient lexical processing is vulnerable to suboptimal listening climates, and that processing under these conditions reveals the continuous nature of the impairment of linguistic behaviors observed in individuals with aphasia.

Unilateral brain damage effects on processing homonymous and polysemous words

Using an auditory semantic priming paradigm, the present study investigated the abilities of left-hemisphere-damaged (LHD) non-fluent aphasic, right-hemisphere-damaged (RHD) and normal control individuals to access, out of context, the multiple meanings of three types of ambiguous words, namely homonyms (e.g., “punch”), metonymies (e.g., “rabbit”), and metaphors (e.g., “star”). In addition, the study tested certain predictions of the “suppression deficit” and “coarse semantic coding” hypotheses that have been proposed to account for the linguistic deficits typically observed after RH damage. Homonymous, metonymous, and metaphorical words were used as primes followed after a short (100 ms) or a long (1000 ms) inter-stimulus interval (ISI) by dominant-meaning-related, subordinate-meaning-related or unrelated target words. No significant group effects were found, and for both ISIs, dominant- and subordinate-related targets were facilitated relative to unrelated control targets for the homonymy and metonymy conditions. In contrast, for the metaphor condition, only targets related to the dominant meaning were facilitated. These findings provide only partial support for the “suppression deficit” hypothesis and no support for the “coarse semantic coding” hypothesis (as interpreted herein) indicating that patients with focal LH or RH damage can access the multiple meanings of ambiguous words and exhibit processing abilities comparable to those of older normal control subjects, at least at the single-word level.

Distinct and shared cortical regions of the human brain activated by pictorial depictions versus verbal descriptions: an fMRI study

Using fMRI, we observed that there were functionally disjunctive regions in the human brain that were specifically activated during the silent reading of sentences (i.e., the symbolical representation at the propositional level) but not during the perception of arranged objects (i.e., analogical representation), or vice versa: Parts of the left and right lingual gyri, the left fusiform gyrus, the left and right inferior occipital gyri, the right cuneus, and the left middle occipital gyrus were activated exclusively during the silent reading of sentences, whereas perception of the arranged objects activated distinct regions in the lingual gyrus, the declive, the fusiform gyrus, and the cuneus in the right hemisphere. A large proportion (86% in cortical volume) of the occipito-temporal regions was functionally conjunctive: these neural structures were activated during both silent reading of sentences and perception of arranged objects. We observed a similar trend of functional disjunction and conjunction between single words (the symbolical mode at the lexical level) and single objects (analogical mode): the degree of functional conjunction in the latter case was about 96%. These results suggest that the degree of functional disjunction between the pictorial depictions and the verbal descriptions tended to increase as the complexity of mental representation increased from the single word (lexical) level (4%) to the sentence (propositional) level (14%).

Dissociation of Lexical Syntax and Semantics: Evidence from Focal Cortical Degeneration

The question of whether information relevant to meaning (semantics) and structure (syntax) relies on a common language processor or on separate subsystems has proved difficult to address definitively because of the confounds involved in comparing the two types of information. At the sentence level syntactic and semantic judgments make different cognitive demands, while at the single word level, the most commonly used syntactic distinction (between nouns and verbs) is confounded with a fundamental semantic difference (between objects and actions). The present study employs a different syntactic contrast (between count nouns and mass nouns), which is crossed with a semantic difference (between naturally occurring and man-made substances) applying to words within a circumscribed semantic field (foodstuffs). We show, first, that grammaticality judgments of a patient with semantic dementia are indistinguishable from those of a group of age-matched controls, and are similar regardless of the status of his semantic knowledge about the item. In a second experiment we use the triadic task in a group of age-matched controls to show that similarity judgments are influenced not only by meaning (natural vs. manmade), but also implicitly by syntactic information (count vs. mass). Using the same task in a patient with semantic dementia we show that the semantic influences on the syntactic dimension are unlikely to account for this pattern in normals. These data are discussed in relation to modular vs. nonmodular models of language processing, and in particular to the semantic-syntactic distinction.

Acoustic Communication of Emotions: Processing of Emotional Prosody. An Investigation on Single Word Level using fMRI

Perception of emotional prosody plays an important role in every day social life. However, the underlying neuronal circuits are far from being identified. The objective of our study was to find out more about the neuronal networks involved in the processing of emotional speech on the single word level by means of fMRI. 13 young healthy subjects were tested in an auditory oddball paradigm where frequent standard words (“Anna“, p=0.7) and infrequent target words (“Anni“, p=0.1) were presented via headphones. The subjects had to press a button each time they heard the target word “Anni“. Both words, standard and the target, were spoken in a neutral tone. Additionally, infrequent words “Anna“ spoken in a happy (p=0.1) or sad (p=0.1) tone were presented as emotional oddballs. Functional MR images were acquired for each stimulus and then statistical parametrical maps (SPMs) were calculated for each subject and for a one-sample t-test. The contrasts “happy vs. neutral condition“ and “sad vs. neutral condition“ revealed activations in the middle gyrus of the temporal lobe and in the frontal opercular cortex bilaterally but with the main focus on the right side, suggesting a lateralization of emotional prosody processing to the right hemisphere already on the single word level. The results are discussed with respect to the relevant literature, the ecological validity and the limits of the experiment.

The lack of focused anticipation of verbal information in stutterers: a magnetoencephalographic study

The motivation of this work was to investigate stuttering—a disorder of speech motor control—in the light of preparatory neural activity of voluntary movements related to speech. To this end, brain activity was recorded with a whole cortex magnetoencephalograph (MEG) in developmental stutterers and nonstutterers while three different tasks of single-word reading were performed. Visually presented words had to be silently read immediately after word presentation (condition 1), spoken aloud immediately after word presentation (condition 2), or spoken aloud after a delay of 1.3 s as indicated by a second visual stimulus (condition 3). Condition 2 clearly showed marked neurophysiological differences between stutterers and nonstutterers. Only nonstutterers showed clear neural activity before speech onset, which is interpreted as being linked to visual word presentation and to reflect focused verbal anticipation. This prespeech activity might reflect the “Bereitschaftsfeld2” (BF2) that is the later component of the “Bereitschaftsfeld”, a well-known preparatory activity described for many other voluntary movements. Our results strongly link the lack of such preparatory brain activity at the single-word level to the disability of fluent speech in stutterers. The present results strongly support the notion that stuttering is related to impaired focused attention or anticipation.

The lack of focused anticipation of verbal information in stutterers: a magnetoencephalographic study

The motivation of this work was to investigate stuttering—a disorder of speech motor control—in the light of preparatory neural activity of voluntary movements related to speech. To this end, brain activity was recorded with a whole cortex magnetoencephalograph (MEG) in developmental stutterers and nonstutterers while three different tasks of single-word reading were performed. Visually presented words had to be silently read immediately after word presentation (condition 1), spoken aloud immediately after word presentation (condition 2), or spoken aloud after a delay of 1.3 s as indicated by a second visual stimulus (condition 3). Condition 2 clearly showed marked neurophysiological differences between stutterers and nonstutterers. Only nonstutterers showed clear neural activity before speech onset, which is interpreted as being linked to visual word presentation and to reflect focused verbal anticipation. This prespeech activity might reflect the “Bereitschaftsfeld2” (BF2) that is the later component of the “Bereitschaftsfeld”, a well-known preparatory activity described for many other voluntary movements. Our results strongly link the lack of such preparatory brain activity at the single-word level to the disability of fluent speech in stutterers. The present results strongly support the notion that stuttering is related to impaired focused attention or anticipation.

A positron emission tomography study of presurgical language mapping in a bilingual patient with a left posterior temporal cavernous angioma

In an attempt to gain a better understanding of how different languages are represented in the human brain, a French–English bilingual patient was studied with positron emission tomography (PET) before undergoing surgery for a left posterior temporal cavernous angioma. When a silent baseline was subtracted from the synonym generation and word repetition tasks in English and in French, peaks in the left posterior temporal region were observed just above and adjacent to the lesion. When word repetition was subtracted from synonym generation, the most significant cortical CBF increases were observed in the left inferior frontal gyrus in both languages. These findings suggest that at least at the single-word level, age of acquisition is not a significant factor in determining functional organization in the brain. Comparison of PET presurgical language mapping and electrical stimulation of the cortex under local anesthesia provided converging evidence to validate the PET findings. The functional imaging literature offers few instances of single-case reports on how the representation of specific linguistic abilities in each language may be related to the presence of a lesion in a bilingual speaker. Such studies offer another perspective for the understanding of the organization of language systems in the brain.

Cerebral Organization in a Right-handed Trilingual Patient with Right-hemisphere Speech: a Positron Emission Tomography Study

Using the method of positron emission tomography, combined with word-generation tasks, we had the opportunity to examine the cerebral representation of multiple languages in the brain in a right-handed patient, RA, with known right-hemisphere speech representation as determined by intracarotid sodium amobarbital testing. Similar patterns of cerebral blood flow were observed across all three languages (French, Spanish and English), when synonym generation was compared with a silent resting baseline. In particular, several regions in the right inferior frontal cortex were activated. These foci are in locations corresponding to those observed in the left hemisphere in normal right-handed volunteers with presumed left-hemisphere dominance, and in patients known to be left-hemisphere dominant for speech. The lack of anatomical separation of the three languages within the same individual, who acquired two languages early and one language later in life, suggests that at least at this single-word level of analysis, age of acquisition was not a significant factor in the determining of functional organization in the brain.

Cerebral Organization in a Right-handed Trilingual Patient with Right-hemisphere Speech: a Positron Emission Tomography Study

Using the method of positron emission tomography, combined with word-generation tasks, we had the opportunity to examine the cerebral representation of multiple languages in the brain in a right-handed patient, RA, with known right-hemisphere speech representation as determined by intracarotid sodium amobarbital testing. Similar patterns of cerebral blood flow were observed across all three languages (French, Spanish and English), when synonym generation was compared with a silent resting baseline. In particular, several regions in the right inferior frontal cortex were activated. These foci are in locations corresponding to those observed in the left hemisphere in normal right-handed volunteers with presumed left-hemisphere dominance, and in patients known to be left-hemisphere dominant for speech. The lack of anatomical separation of the three languages within the same individual, who acquired two languages early and one language later in life, suggests that at least at this single-word level of analysis, age of acquisition was not a significant factor in the determining of functional organization in the brain.