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Hallucinated voices are common across psychiatric and non-clinical groups. The predominant cognitive theory about the impact of voices posits that beliefs about voice power ('Omnipotence') and voice intent ('Malevolence'/'Benevolence') play a key role in determining emotional and behavioral reactions. The revised Beliefs about Voices Questionnaire (BAVQ-R) was designed to assess these constructs, together with two styles of responding (Engagement and Resistance). The BAVQ-R is widely used in clinical and research settings, yet it has not received validation of its constructs and factor structure. This study examined the factor structure of the BAVQ-R by combining datasets from five study centers, comprising 450 participants (belief constructs) and 269 participants (response styles), and using confirmatory and exploratory factor analysis. Findings failed to support a three factor belief model, instead showing a two-factor structure ('Persecutory beliefs' combining Omnipotence and Malevolence constructs, and a Benevolent construct). Emotional and behavioral items did not separate. Overall, results showed that (i) a two-factor model of beliefs (Persecutory and Benevolent beliefs) provides a better fit to the data than a three-factor model, and (ii) emotional and behavioral modes of responding items should not be separated. Theoretical implications of this finding are discussed in relation to the research and therapy.

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Individuals with developmental language impairment can show deficits into adulthood. This suggests that neural networks related to their language do not normalize with time. We examined the ability of 16 adults with and without impaired language to learn individual words in an unfamiliar language. Adults with impaired language were able to segment individual words from running speech, but needed more time to do so than their normal-language peers. ICA analysis of fMRI data indicated that adults with language impairment activate a neural network that is comparable to that of adults with normal language. However, a regional analysis indicated relative hyperactivation of a collection of regions associated with language processing. These results are discussed with reference to the Statistical Learning Framework and the sub-skills thought to relate to word segmentation.

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Learners of most languages are faced with the task of acquiring words to talk about number and quantity. Much is known about the order of acquisition of number words as well as the cognitive and perceptual systems and cultural practices that shape it. Substantially less is known about the acquisition of quantifiers. Here, we consider the extent to which systems and practices that support number word acquisition can be applied to quantifier acquisition and conclude that the two domains are largely distinct in this respect. Consequently, we hypothesize that the acquisition of quantifiers is constrained by a set of factors related to each quantifier's specific meaning. We investigate competence with the expressions for "all," "none," "some," "some…not," and "most" in 31 languages, representing 11 language types, by testing 768 5-y-old children and 536 adults. We found a cross-linguistically similar order of acquisition of quantifiers, explicable in terms of four factors relating to their meaning and use. In addition, exploratory analyses reveal that language- and learner-specific factors, such as negative concord and gender, are significant predictors of variation.

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Artificial language studies have demonstrated that learners are able to segment individual word-like units from running speech using the transitional probability information. However, this skill has rarely been examined in the context of natural languages, where stimulus parameters can be quite different. In this study, two groups of English-speaking learners were exposed to Norwegian sentences over the course of three fMRI scans. One group was provided with input in which transitional probabilities predicted the presence of target words in the sentences. This group quickly learned to identify the target words and fMRI data revealed an extensive and highly dynamic learning network. These results were markedly different from activation seen for a second group of participants. This group was provided with highly similar input that was modified so that word learning based on syllable co-occurrences was not possible. These participants showed a much more restricted network. The results demonstrate that the nature of the input strongly influenced the nature of the network that learners employ to learn the properties of words in a natural language.

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PURPOSE: This experiment investigated whether input variability would affect initial learning of noun gender subcategories in an unfamiliar, natural language (Russian), as it is known to assist learning of other grammatical forms. METHOD: Forty adults (20 men, 20 women) were familiarized with examples of masculine and feminine Russian words. Half of the participants were familiarized with 32 different root words in a high-variability condition. The other half were familiarized with 16 different root words, each repeated twice for a total of 32 presentations in a high-repetition condition. Participants were tested on untrained members of the category to assess generalization. Familiarization and testing was completed 2 additional times. RESULTS: Only participants in the high-variability group showed evidence of learning after an initial period of familiarization. Participants in the high-repetition group were able to learn after additional input. Both groups benefited when words included 2 cues to gender compared to a single cue. CONCLUSIONS: The results demonstrate that the degree of input variability can influence learners' ability to generalize a grammatical subcategory (noun gender) from a natural language. In addition, the presence of multiple cues to linguistic subcategory facilitated learning independent of variability condition.

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For the majority of the population, language is a left-hemisphere lateralized function. During childhood, a pattern of increasing left lateralization for language has been described in brain imaging studies, suggesting that this trait develops. This development could reflect change due to brain maturation or change due to skill acquisition, given that children acquire and refine language skills as they mature. We test the possibility that skill acquisition, independent of age-associated maturation can result in shifts in language lateralization in classic language cortex. We imaged adults exposed to an unfamiliar language during three successive fMRI scans. Participants were then asked to identify specific words embedded in Norwegian sentences. Exposure to these sentences, relative to complex tones, resulted in consistent activation in the left and right superior temporal gyrus. Activation in this region became increasingly left-lateralized with repeated exposure to the unfamiliar language. These results demonstrate that shifts in lateralization can be produced in the short term within a learning context, independent of maturation.

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The present study reports the results of a cross-cultural analysis of the role of phonetic and semantic cues in verbal learning and memory. A newly developed memory test procedure, the Bergen-Tucson Verbal Learning Test (BTVLT), expands earlier test procedures as phonetic cues are applied in addition to semantic cues in a cued recall procedure. Samples of reading disabled and typically developed adolescents from the US and from Norway were recruited as voluntary participants. The results indicate that the stimulus materials chosen for the memory test are working well in both American and in Norwegian samples, yielding acquisition results comparable to similar list learning procedures, and also yielding high internal consistency across learning trials. The procedure also reliably differentiates between reading disabled samples in both languages, and also yields cross-cultural differences that seem to reflect differences in transparency and differences in the orthography of the included languages. The BTVLT with its focus on phonetic coding is a promising supplement to established tests of verbal memory for assessment of reading and language impaired individuals.

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The present study investigated a possible connection between speech processing and cochlear function. Twenty-two subjects with age range from 18 to 39, balanced for gender with normal hearing and without any known neurological condition, were tested with the dichotic listening (DL) test, in which listeners were asked to identify CV-syllables in a nonforced, and also attention-right, and attention-left condition. Transient evoked otoacoustic emissions (TEOAEs) were recorded for both ears, with and without the presentation of contralateral broadband noise. The main finding was a strong negative correlation between language laterality as measured with the dichotic listening task and of the TEOAE responses. The findings support a hypothesis of shared variance between central and peripheral auditory lateralities, and contribute to the attentional theory of auditory lateralization. The results have implications for the understanding of the cortico-fugal efferent control of cochlear activity.

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The influence of posttraumatic stress disorder (PTSD) on cognitive control and auditory attention modulation was examined with the use of a dichotic-listening (DL) task. The participants were 45 war-exposed refugees. The PTSD group comprised 22 participants meeting the DSM-IV criteria for PTSD, and the Control group comprised 23 war-exposed participants without PTSD. Both groups were tested with a consonant-vowel syllables DL task under three different attentional instructions. The two groups did not differ in the non-forced and forced-right conditions and showed, as expected, right-ear advantages. The Control group showed, as expected, a left-ear advantage in the forced-left (FL) condition. However, the PTSD group continued to show a right-ear advantage--and only minor modulation of the performance during the FL condition. This finding suggests that PTSD is associated with a reduced capacity for top-down attentional control of a bottom-up or stimulus-driven effect. The result shows that participants with PTSD have impaired cognitive control functions when tested on information processing of neutral stimuli.

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The present study focuses on language laterality as measured with dichotic listening (DL) to consonant-vowel syllables (CV syllables) in refugees with post-traumatic stress disorder (PTSD). PTSD is associated with impaired callosal transfer and with increased right hemisphere activation and impaired executive skills that could influence the processing of dichotic stimuli. A total of 22 participants with PTSD were compared to 23 participants without a diagnosis of PTSD. All participants had similar experiences of acts of war and political violence. They were tested with dichotic listening to CV syllables with free recall and directed attention following the forced attention paradigm. The PTSD group showed increased right ear advantage due to impaired left ear reporting and also smaller attention modulation compared to the control group, and the performance shared variance with self-report measures of arousal and intrusive memories. The results are discussed towards a model of impaired functionality of the frontal lobe and right hemisphere versus impaired callosal transfer, both yielding predictions for the processing of the left ear input and the ability to attention modulation of the performance.

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OBJECTIVE: The present study was designed to test some assumptions about screening procedures for ADHD in adults. METHOD: Twenty-eight incarcerated male adults completed a self report scale of attention deficits as a part of an examination of attention and reading skills. Further assessment of attention included a battery of tests that assessed vigilance, attention shifts, and other aspects of cognitive control. RESULTS: Fifty seven percent of the sample showed test performance indicating a high probability of ADHD. Correlation analyses yielded significant effects for self report scales and objective tests of attention. CONCLUSION: The results support the assumption that the self report measures share a significant part of the variance with tests of attention commonly used in clinical assessment. However, the risk of making both false positive and false negative inferences about ADHD is present, as the specificity and the sensitivity of the rating scale needs to be further explored.

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The present study focussed on the determinants for effective solving of the Wordchains Test (WCT) in a normative sample of Norwegian junior high-school students. Forty voluntary participants from a rural school district in Western Norway completed the WCT along with tests of general intellectual capacity, single word and non-word reading, auditory working memory, and visual scanning. All measures correlated significantly with each other except for general non-verbal abilities were not correlated with visual scanning. A stepwise multiple regression analysis, using the WCT as the dependent variable, yielded a model that included single word reading, letter recognition, and working memory as independent variables. This model accounted for 75% of the variance in WCT performance. This finding suggests that phonological skills only have an indirect influence on WCT performance. Thus, the core deficit in dyslexia, i.e. impaired phonological skills, may be related to the development of word recognition skills, but have no direct effect on the WCT performance in a normative sample.

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Previous language learning research reveals that the statistical properties of the input offer sufficient information to allow listeners to segment words from fluent speech in an artificial language. The current pair of studies uses a natural language to test the ecological validity of these findings and to determine whether a listener's language background influences this process. In Study 1, the "guessibility" of potential test words from the Norwegian language was presented to 22 listeners who were asked to differentiate between true words and nonwords. In Study 2, 22 adults who spoke one of 12 different primary languages learned to segment words from continuous speech in an implicit language learning paradigm. The task consisted of two sessions, approximately three weeks apart, each requiring participants to listen to 7.2 minutes of Norwegian sentences followed by a series of bisyllabic test items presented in isolation. The participants differentially accepted the Norwegian words and Norwegian-like nonwords in both test sessions, demonstrating the capability to segment true words from running speech. The results were consistent across three broadly-defined language groups, despite differences in participants' language background.

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The present study examined mechanisms underlying verbal memory impairments in patients with posttraumatic stress disorder (PTSD). Earlier studies have reported that the verbal learning and memory alterations in PTSD are related to impaired encoding, but the use of encoding and organizational strategies in patients with PTSD has not been fully explored. This study examined organizational strategies in 21 refugees/immigrants exposed to war and political violence who fulfilled DSM-IV criteria for chronic PTSD compared with a control sample of 21 refugees/immigrants with similar exposure, but without PTSD. The California Verbal Learning Test was administered to examine differences in organizational strategies and memory. The semantic clustering score was slightly reduced in both groups, but the serial cluster score was significantly impaired in the PTSD group and they also reported more items from the recency region of the list. In addition, intrusive errors were significantly increased in the PTSD group. The data support an assumption of changed memory strategies in patients with PTSD associated with a specific impairment in executive control. However, memory impairment and the use of ineffective learning strategies may not be related to PTSD symptomatology only, but also to self-reported symptoms of depression and general distress.

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BACKGROUND: Qualitative review papers have indicated that verbal memory impairment is found to be the most consistent cognitive impairment related to PTSD. These review papers have used qualitative methods to describe the effects, and consequently they have not been able to estimate the strength of the memory-PTSD association. METHODS: This meta-analysis of 28 studies examined the empirical evidence for this relationship, and factors affecting the results. RESULTS: Overall, the results showed medium effect sizes in patients with PTSD compared to controls on verbal memory across studies. Marked impairment was found in the patient groups compared to healthy controls, while modest impairment was found compared to exposed non-PTSD controls. Meta-analyses found strongest effects in war veterans compared to sexual and physical assault related PTSD. Rather unexpectedly no effect was found for the sexually abused PTSD groups compared to exposed controls. The analyses further showed that the effect was dependent on the test procedures used. The studies using WMS and AVLT had stronger effects than studies using CVLT. LIMITATIONS: Insufficient data were available to analyze a more complete attention-memory profile. CONCLUSIONS: This meta-analysis confirms that verbal memory impairment is present in adults with PTSD, and they are consistent across studies. This impairment should be the focus of work in clinical settings.

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The present study focuses on verbal learning and memory alterations in refugees with posttraumatic stress disorder, and whether the alterations are related to attention, acquisition, storage, or retrieval. Twenty-one refugees exposed to war and political violence with chronic PTSD, were compared to an exposed control sample of 21 refugees without PTSD. No differences were found in attention span, but tests of verbal memory showed less efficient learning in the PTSD sample. Group differences in delayed recall could be explained by learning efficiency. No differences were seen in recognition memory. These results indicate that memory alterations in PTSD are related to impaired acquisition and less effective encoding of the memory material and not to impaired attention span and/or impaired retrieval. Controlling for specific PTSD symptom clusters and self-reported depression showed that the intrusion subscale and depressive reactions are the most important symptoms in understanding the memory alterations in PTSD.

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This study focused on the relationship between school performance and performance on a dichotic listening (DL) task in dyslexic children. Dyslexia is associated with impaired phonological processing, related to functions in the left temporal lobe. DL is a frequently used task to assess functions of the left temporal lobe. Due to the predominance of the contralateral neuronal pathways, a right ear advantage in the DL task reflects the superior processing capacity for the right ear stimulus in the left hemisphere (Kimura, 1963). Previous studies using DL in dyslexia are, however, inconclusive, and may reflect degree of severity of dyslexia. The aim of the present study was therefore to investigate lateralized processing in two sub-groups of dyslexia, differing in symptom severity. Two groups of dyslexic 12-year-old children and an age-matched control group were tested with a consonant-vowel DL task. The two dyslexia groups differed in severity through how they responded to training efforts being made in their schools, while otherwise being matched for age, IQ and diagnosis. The D1 (respondent group) group showed a DL performance pattern similar to the control group, i.e. a right ear advantage, while the D2 (non-respondent) group failed to show a right ear advantage on the DL task. The performance on the DL task by the two dyslexia groups may provide better insight as to the degree of reading and writing impairment in dyslexia. 'Cracking the code' and acquiring automatized literacy skills may seem harder for the D2 group children compared to the D1 children. Also, the present study points to the use of DL as a valid assessment tool in clinical work to improve differential diagnoses, particularly in relation to measures of school performance.

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UNLABELLED: Twenty-two subjects with chronic PTSD were compared to 23 subjects with no diagnoses (NPD) on tests of executive functioning (EF) that are assumed to have clinical significance after exposure to political violence. METHOD: The three cognitive components of EF, intentionality, inhibition and executive memory [Burgess, P. W., Alderman, N., Evans, J., Emslie, H., Wilson, B. A. (1998). The ecological validity of tests of executive function. Journal of the International Neuropsychological Society, 4, 547-58], were measured using the Tower of London, Stroop Color-Word Test and Wisconsin Card Sorting Test (WCST), respectively. RESULTS: The PTSD group was impaired on tasks measuring automatic processing and executive memory. Executive memory problems were related to elevated posttraumatic symptoms, but the executive components intentionality and inhibition did not differentiate the groups. Arousal and intrusive symptoms had no impact on intentionality. CONCLUSION: Posttraumatic symptoms are related to automatic processing problems and impairment in executive memory. Observed dysfunctions in mental flexibility could have a negative impact on the cognitive processing of traumatic memory, thus preventing from recovery.

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This study addresses the effects of verbal versus nonverbal (tone) shifts of attention on dichotic listening (DL) performance with children. Theoretically, a tonal cue may be more effective in increasing attention than a verbal cue following instruction. The inconsistency of studies reporting substantial effects of attention on ear asymmetries in children with or without learning disabilities (LDs) may be due to a developmental difference in their ability to use verbal or tone cues to select stimuli for recall. Participants included 30 right-handed children (15 control, 15 with LDs) with a mean age of 10.8 years. Each participant received 60 trials of a monaural tone cue task, 60 trials of a binaural verbal cue task, and 60 trials of a monaural verbal cue task, to direct attention to either the left or right ear before the presentation of consonant-vowel syllable pairs in a DL task. A factorial design analysis of variance yielded a significant right-ear advantage for both groups. More important, the Group x Task interaction was found to be significant, indicating that group performance on ear scores was dependent on type of cueing condition. Whereas all 3 cue conditions were effective in orienting attention for control participants, larger shifts were apparent under both binaural and monaural verbal instructional cue conditions. In contrast, participants with LD showed larger shifts of attention under the tonal cue condition. These results show that control participants have greater ability to focus attention with the use of a verbal cue, whereas participants with LD show greater ability to orient attention with the use of a tone cue in reducing error rates in DL performance.

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Dichotic listening performance is considered a reliable and valid procedure for the assessment of language lateralisation in the brain. However, the documentation of a relationship between language functions and dichotic listening performance is sparse, although it is accepted that dichotic listening measures language perception. In particular, language comprehension should show close correspondence to perception of language stimuli. In the present study, we tested samples of reading-impaired and normally achieving children between 10 and 13 years of age with tests of reading skills, language comprehension, and dichotic listening to consonant-vowel (CV) syllables. A high correlation between the language scores and the dichotic listening performance was expected. However, since the left ear score is believed to be an error when assessing language laterality, covariation was expected for the right ear scores only. In addition, directing attention to one ear input was believed to reduce the influence of random factors, and thus show a more concise estimate of left hemisphere language capacity. Thus, a stronger correlation between language comprehension skills and the dichotic listening performance when attending to the right ear was expected. The analyses yielded a positive correlation between the right ear score in DL and language comprehension, an effect that was stronger when attending to the right ear. The present results confirm the assumption that dichotic listening with CV syllables measures an aspect of language perception and language skills that is related to general language comprehension.

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