Biomedical subjects

James R Booth

Publications and source records attributed to James R Booth.

18 recordsLinked to original sources

PubMed2007

The interaction between orthographic and phonological information in children: an fMRI study.

We examined the neural representations of orthographic and phonological processing in children, while manipulating the consistency between orthographic and phonological information. Participants, aged 9-15, were scanned while performing rhyming and spelling judgments on pairs of visually presented words. The orthographic and phonological similarity between words in the pair was independently manipulated, resulting in four conditions. In the nonconflicting conditions, both orthography and phonology of the words were either (1) similar (lime-dime) or (2) different (staff-gain); in conflicting conditions, words had (3) similar phonology and different orthography (jazz-has) or (4) different phonology and similar orthography (pint-mint). The comparison between tasks resulted in greater activation for the rhyming task in bilateral inferior frontal gyri (BA 45/47), and greater activation for the spelling task in bilateral inferior/superior parietal lobules (BA 40/7), suggesting greater involvement of phonological and semantic processing in the rhyming task, and nonlinguistic spatial processing in the spelling task. Conflicting conditions were more difficult in both tasks and resulted in greater activation in the above regions. The results suggest that when children encounter inconsistency between orthographic and phonological information they show greater engagement of both orthographic and phonological processing.

Acoustic Stimulation↗

PubMed2006

The role of the basal ganglia and cerebellum in language processing.

The roles of the cerebellum and basal ganglia have typically been confined in the literature to motor planning and control. However, mounting evidence suggests that these structures are involved in more cognitive domains such as language processing. In the current study, we looked at effective connectivity (the influence that one brain region has on another) of the cerebellum and basal ganglia with regions thought to be involved in phonological processing, i.e. left inferior frontal gyrus and left lateral temporal cortex. We analyzed functional magnetic resonance imaging data (fMRI) obtained during a rhyming judgment task in adults using dynamic causal modeling (DCM). The results showed that the cerebellum has reciprocal connections with both left inferior frontal gyrus and left lateral temporal cortex, whereas the putamen has unidirectional connections into these two brain regions. Furthermore, the connections between cerebellum and these phonological processing areas were stronger than the connections between putamen and these areas. This pattern of results suggests that the putamen and cerebellum may have distinct roles in language processing. Based on research in the motor planning and control literature, we argue that the putamen engages in cortical initiation while the cerebellum amplifies and refines this signal to facilitate correct decision making.

Adult↗

PubMed2006

Children with reading disorder show modality independent brain abnormalities during semantic tasks.

Neuroimaging studies have suggested that left inferior frontal gyrus, left inferior parietal lobule and left middle temporal gyrus are critical for semantic processing in normal children. The goal of the present functional magnetic resonance imaging (fMRI) study was to determine whether these regions are systematically related to semantic processing in children (9- to 15-year-old) diagnosed with reading disorders (RD). Semantic judgments required participants to indicate whether two words were related in meaning. The strength of semantic association varied continuously from higher association pairs (e.g., king-queen) to lower association pairs (e.g. net-ship). We found that the correlation between association strength and activation was significantly weaker for RD children compared to controls in left middle temporal gyrus and left inferior parietal lobule for both the auditory and the visual modalities and in left inferior frontal gyrus for the visual modality. These results suggest that the RD children have abnormalities in semantic search/retrieval in the inferior frontal gyrus, integration of semantic information in the inferior parietal lobule and semantic lexical representations in the middle temporal gyrus. These deficits appear to be general to the semantic system and independent of modality.

Adolescent↗

PubMed2006

Weaker top-down modulation from the left inferior frontal gyrus in children.

Previous studies have shown that developmental changes in the structure and function of prefrontal regions can continue throughout childhood and adolescence. Our recent results suggested a role for the left inferior frontal cortex in modulating task-dependent shifts in effective connectivity when adults focus on orthographic versus phonological aspects of presented words. Specifically, the top-down influence of the inferior frontal cortex determined whether incoming word-form information from the fusiform gyrus would have a greater impact on the parietal areas involved in orthographic processing or temporal areas involved in phonological processing (Bitan, T., Booth, J.R., Choy, J., Burman, D.D., Gitelman, D.R. and Mesulam, M.-M., 2005. Shifts of Effective Connectivity within a Language Network during Rhyming and Spelling. J. Neurosci. 25, 5397-5403.). In the current study, we find that children displayed an identical pattern of task-dependent functional activations within this network. In comparison to adults, however, children had significantly weaker top-down modulatory influences emanating from the inferior frontal area. Adult language processing may thus involve greater top-down cognitive control compared to children, resulting in less interference from task-irrelevant information.

Adult↗

PubMed2006

Specialization of phonological and semantic processing in Chinese word reading.

The purpose of this study was to examine the neurocognitive network for processing visual word forms in native Chinese speakers using functional magnetic resonance imaging (fMRI). In order to compare the processing of phonological and semantic representations, we developed parallel rhyming and meaning association judgment tasks that required explicit access and manipulation of these representations. Subjects showed activation in left inferior/middle frontal gyri, bilateral medial frontal gyri, bilateral middle occipital/fusiform gyri, and bilateral cerebella for both the rhyming and meaning tasks. A direct comparison of the tasks revealed that the rhyming task showed more activation in the posterior dorsal region of the inferior/middle frontal gyrus (BA 9/44) and in the inferior parietal lobule (BA 40). The meaning task showed more activation in the anterior ventral region of the inferior/middle frontal gyrus (BA 47) and in the superior/middle temporal gyrus (BA 22,21). These findings are consistent with previous studies in English that suggest specialization of inferior frontal regions for the access and manipulation of phonological vs. semantic representations, but also suggest that this specialization extends to the middle frontal gyrus for Chinese. These findings are also consistent with the suggestion that the left middle temporal gyrus is involved in representing semantic information and the left inferior parietal lobule is involved in mapping between orthographic and phonological representations.

Acoustic Stimulation↗

PubMed2006

Developmental and skill effects on the neural correlates of semantic processing to visually presented words.

Functional magnetic resonance imaging (fMRI) was used to explore the neural correlates of semantic judgments to visual words in a group of 9- to 15-year-old children. Subjects were asked to indicate if word pairs were related in meaning. Consistent with previous findings in adults, children showed activation in bilateral inferior frontal gyri (Brodmann area [BA] 47, 45) and left middle temporal gyrus (BA 21). Words with strong semantic association elicited significantly greater activation in bilateral inferior parietal lobules (BA 40), suggesting stronger integration of highly related semantic features. By contrast, words with weak semantic association elicited greater activation in left inferior frontal gyrus (BA 45) and middle temporal gyrus (BA 21), suggesting more difficult feature search and more extensive access to semantic representations. We also examined whether age and skill explained unique variance in the patterns of activation. Increasing age was correlated with greater activation in left middle temporal gyrus (BA 21) and inferior parietal lobule (BA 40), suggesting that older children have more elaborated semantic representations and more complete semantic integration processes, respectively. Decreasing age was correlated with activation in right superior temporal gyrus (BA 22) and decreasing accuracy was correlated with activation in right middle temporal gyrus (BA 21), suggesting the engagement of ancillary systems in the right hemisphere for younger and lower-skill children.

Adolescent↗

PubMed2006

Development of lexical and sentence level context effects for dominant and subordinate word meanings of homonyms.

Nine-ten-and twelve-year-old children (N = 75) read aloud dominant, subordinate or ambiguous bias sentences (N = 120) that ended in a homonym (BALL). After the sentence (1,000 ms), children read aloud targets that were related to the dominant (BAT) or subordinate (DANCE) meaning of the homonym or control targets. Participants were also divided into three reading skill groups based on an independent measure of single word oral reading accuracy. There were three main developmental and reading skill findings. First, 9-year-olds and low skill readers showed lexical level facilitation in accuracy. Second, 9- and 10-year-olds or low and moderate skill readers showed lexical level facilitation in reaction time. Third, 12-year-olds or high skill readers showed sentence level facilitation in reaction time with high skill readers additionally showing sentence level inhibition in reaction time. These results show that lexical level context effects decreased and that sentence level context effects increased with development and skill. These results are discussed in terms of connectionist models of visual word recognition that incorporate distributed attractor principles.

Child↗

PubMed2006

Deficient orthographic and phonological representations in children with dyslexia revealed by brain activation patterns.

BACKGROUND: The current study examined the neuro-cognitive network of visual word rhyming judgment in 14 children with dyslexia and 14 age-matched control children (8- to 14-year-olds) using functional magnetic resonance imaging (fMRI). METHODS: In order to manipulate the difficulty of mapping orthography to phonology, we used conflicting and non-conflicting trials. The words in conflicting trials either had similar orthography but different phonology (e.g., pint-mint) or similar phonology but different orthography (e.g., jazz-has). The words in non-conflicting trials had similar orthography and phonology (e.g., gate-hate) or different orthography and phonology (e.g., press-list). RESULTS: There were no differences in brain activation between the controls and children with dyslexia in the easier non-conflicting trials. However, the children with dyslexia showed less activation than the controls in left inferior frontal gyrus (BA 45/44/47/9), left inferior parietal lobule (BA 40), left inferior temporal gyrus/fusiform gyrus (BA 20/37) and left middle temporal gyrus (BA 21) for the more difficult conflicting trials. For the direct comparison of conflicting minus non-conflicting trials, controls showed greater activation than children with dyslexia in left inferior frontal gyrus (BA 9/45/46) and medial frontal gyrus (BA 8). Children with dyslexia did not show greater activation than controls for any comparison. CONCLUSIONS: Reduced activation in these regions suggests that children with dyslexia have deficient orthographic representations in ventral temporal cortex as well as deficits in mapping between orthographic and phonological representations in inferior parietal cortex. The greater activation for the controls in inferior frontal gyrus could reflect more effective top-down modulation of posterior representations.

Adolescent↗

PubMed2005

Developmental changes in the neural correlates of semantic processing.

Functional magnetic resonance imaging (fMRI) was used to explore the neural correlates of semantic judgments in the auditory modality in a group of 9- to 15-year-old children. Subjects were required to indicate if word pairs were related in meaning. Consistent with previous findings in adults, children showed activation in bilateral superior temporal gyri (BA 22) for recognizing spoken words as well as activations in bilateral inferior frontal gyri (BAs 47, 45) and left middle temporal gyrus (BA 21) for semantic processing. The neural substrates of semantic association and age differences were also investigated. Words with strong semantic association elicited significantly greater activation in the left inferior parietal lobule (BA 40), whereas words with weak semantic association elicited activation in left inferior frontal gyrus (BAs 47/45). Correlations with age were observed in the left middle temporal gyrus (BA 21) and the right inferior frontal gyrus (BA 47). The pattern of results for semantic association implies that the left inferior parietal lobule effectively integrates highly related semantic features and the left inferior frontal gyrus becomes more active for words that require a greater search for semantic associations. The developmental results suggest that older children recruit the right inferior frontal gyrus as they conduct a broader semantic search and the left middle temporal gyrus to provide more efficient access to semantic representations.

Adolescent↗

PubMed2005

Differential prefrontal-temporal neural correlates of semantic processing in children.

This study used functional magnetic resonance imaging (fMRI) to examine brain-behavior correlations in a group of 16 children (9- to 12-year-olds). Activation was measured during a semantic judgment task presented in either the visual or auditory modality that required the individual to determine whether a final word was related in meaning to one of two previous words (e.g., found-tank-lost). The main finding was that higher performers (i.e., accuracy) were associated with more activation in posterior representational systems including the inferior and middle temporal gyri, whereas lower performers were associated with more activation in anterior regions including the inferior and middle frontal gyri. This pattern of results was interpreted as reflecting an elaborated semantic representational system in temporal areas for the high accuracy performers that allowed them to efficiently and accurately make meaning based judgments. The low accuracy performers may have an inaccurate or weakly interconnected semantic system that results in greater use of frontal areas in a feature selection process.

Analysis of Variance↗

PubMed2005

Shifts of effective connectivity within a language network during rhyming and spelling.

We used functional magnetic resonance imaging to examine task-specific modulations of effective connectivity within a left-hemisphere language network during spelling and rhyming judgments on visually presented words. We identified sites showing task-specific activations for rhyming in the lateral temporal cortex (LTC) and for spelling in the intraparietal sulcus (IPS). The inferior frontal gyrus (IFG) and fusiform gyrus were engaged by both tasks. Dynamic causal modeling showed that each task preferentially strengthened modulatory influences converging on its task-specific site (LTC for rhyming, IPS for spelling). These remarkably selective and symmetrical findings demonstrate that the nature of the behavioral task dynamically shifts the locus of integration (or convergence) to the network component specialized for that task. Furthermore, they suggest that the role of the task-selective areas is to provide a differential synthesis of incoming information rather than providing differential control signals influencing the activity of other network components. Our findings also showed that switching tasks led to changes in the target area influenced by the IFG, suggesting that the IFG may play a pivotal role in setting the cognitive context for each task. We propose that task-dependent shifts in effective connectivity are likely to be mediated through top-down modulations from the IFG to the task-selective regions in a way that differentially enhances their sensitivity to incoming word-form information.

Adult↗

PubMed2005

Larger deficits in brain networks for response inhibition than for visual selective attention in attention deficit hyperactivity disorder (ADHD).

BACKGROUND: Brain activation differences between 12 control and 12 attention deficit hyperactivity disorder (ADHD) children (9- to 12-year-olds) were examined on two cognitive tasks during functional magnetic resonance imaging (fMRI). METHOD: Visual selective attention was measured with the visual search of a conjunction target (red triangle) in a field of distracters and response inhibition was measured with a go/no-go task. RESULTS: There were limited group differences in the selective attention task, with control children showing significantly greater intensity of activation in a small area of the superior parietal lobule region of interest. There were large group differences in the response inhibition task, with control children showing significantly greater intensity of activation in fronto-striatal regions of interest including the inferior, middle, superior and medial frontal gyri as well as the caudate nucleus and globus pallidus. CONCLUSION: The widespread hypoactivity for the ADHD children on the go/no-go task is consistent with the hypothesis that response inhibition is a specific deficit in attention deficit hyperactivity disorder.

Attention↗

PubMed2004

Brain-behavior correlation in children depends on the neurocognitive network.

We examined brain-behavior correlations in 12 children (age range 9.3 to 11.7 years) during a selective attention task that required the visual search of a conjunction of features and during a response inhibition task that required the inhibition of a pre-potent response during "no-go" blocks. We found that the association between performance in these tasks and brain activation as measured by functional magnetic resonance imaging (fMRI) depended on the neurocognitive network. Specifically, better performance during the no-go task was associated with greater activation in the response inhibition network including the prefrontal cortex and basal ganglia. In contrast, better performance during the visual search task was associated with less activation in the selective attention network including superior parietal lobule and lateral premotor cortex. These results show that the relation of performance to the magnitude of neural activation is complex and may display differential relationships based on the cognitive domain, anatomical region, and perhaps also developmental stage.

Attention↗

PubMed2004

Development of brain mechanisms for processing orthographic and phonologic representations.

Developmental differences in the neurocognitive networks for lexical processing were examined in 15 adults and 15 children (9- to 12-year-olds) using functional magnetic resonance imaging (fMRI). The lexical tasks involved spelling and rhyming judgments in either the visual or auditory modality. These lexical tasks were compared with nonlinguistic control tasks involving judgments of line patterns or tone sequences. The first main finding was that adults showed greater activation than children during the cross-modal lexical tasks in a region proposed to be involved in mapping between orthographic and phonologic representations. The visual rhyming task, which required conversion from orthography to phonology, produced greater activation for adults in the angular gyrus. The auditory spelling task, which required the conversion from phonology to orthography, also produced greater activation for adults in the angular gyrus. The greater activation for adults suggests they may have a more elaborated posterior heteromodal system for mapping between representational systems. The second main finding was that adults showed greater activation than children during the intra-modal lexical tasks in the angular gyrus. The visual spelling and auditory rhyming did not require conversion between orthography and phonology for correct performance but the adults showed greater activation in a system implicated for this mapping. The greater activation for adults suggests that they have more interactive convergence between representational systems during lexical processing.

Acoustic Stimulation↗

PubMed2003

Relation between brain activation and lexical performance.

Functional magnetic resonance imaging (fMRI) was used to determine whether performance on lexical tasks was correlated with cerebral activation patterns. We found that such relationships did exist and that their anatomical distribution reflected the neurocognitive processing routes required by the task. Better performance on intramodal tasks (determining if visual words were spelled the same or if auditory words rhymed) was correlated with more activation in unimodal regions corresponding to the modality of sensory input, namely the fusiform gyrus (BA 37) for written words and the superior temporal gyrus (BA 22) for spoken words. Better performance in tasks requiring cross-modal conversions (determining if auditory words were spelled the same or if visual words rhymed), on the other hand, was correlated with more activation in posterior heteromodal regions, including the supramarginal gyrus (BA 40) and the angular gyrus (BA 39). Better performance in these cross-modal tasks was also correlated with greater activation in unimodal regions corresponding to the target modality of the conversion process (i.e., fusiform gyrus for auditory spelling and superior temporal gyrus for visual rhyming). In contrast, performance on the auditory spelling task was inversely correlated with activation in the superior temporal gyrus possibly reflecting a greater emphasis on the properties of the perceptual input rather than on the relevant transmodal conversions.

Acoustic Stimulation↗

PubMed2003

Neural development of selective attention and response inhibition.

Brain activation differences between 12 children (9- to 12-year-olds) and 12 adults (20- to 30-year-olds) were examined on two cognitive tasks during functional magnetic resonance imaging (fMRI). Spatial selective attention was measured with the visual search for a conjunction target (red triangle) in a field of distracters and response inhibition was measured with a go no-go task. There were small developmental differences in the selective attention task, with children showing greater activation than adults in the anterior cingulate and thalamus. There were large developmental differences in the response inhibition task, with children showing greater activation than adults in a fronto-striatal network including middle cingulate, medial frontal gyrus, medial aspects of bilateral superior frontal gyrus, and the caudate nucleus on the left. Children also showed greater bilateral activation for the response inhibition task in posterior cingulate, thalamus and the hippocampo-amygdaloid region. The extensive developmental differences on the response inhibition task are consistent with the prolonged maturation of the fronto-striatal network.

Adult↗

PubMed2002

Modality independence of word comprehension.

Functional magnetic resonance imaging (fMRI) was used to examine the functional anatomy of word comprehension in the auditory and visual modalities of presentation. We asked our subjects to determine if word pairs were semantically associated (e.g., table, chair) and compared this to a reference task where they were asked to judge whether word pairs rhymed (e.g., bank, tank). This comparison showed task-specific and modality-independent activation for semantic processing in the heteromodal cortices of the left inferior frontal gyrus (BA 46, 47) and left middle temporal gyrus (BA 21). There were also modality-specific activations in the fusiform gyrus (BA 37) for written words and in the superior temporal gyrus (BA 22) for spoken words. Our findings are consistent with the hypothesis that word form recognition (lexical encoding) occurs in unimodal cortices and that heteromodal brain regions in the anterior as well as posterior components of the language network subserve word comprehension (semantic decoding).

Adult↗

PubMed2002

Functional anatomy of intra- and cross-modal lexical tasks.

Functional magnetic resonance imaging (fMRI) was used to examine lexical processing in normal adults (20-35 years). Two tasks required only intramodal processing (spelling judgments with visual input and rhyming judgments with auditory input) and two tasks required cross-modal processing between phonologic and orthographic representations (spelling judgments with auditory input and rhyming judgments with visual input). Each task led to greater activation in the unimodal association area concordant with the modality of input, namely fusiform gyrus (BA 19, 37) for written words and superior temporal gyrus (BA 22, 42) for spoken words. Cross-modal tasks generated greater activation in posterior heteromodal regions including the supramarginal and angular gyri (BA 40, 39). Cross-modal tasks generated additional activation in unimodal areas representing the target of conversion, superior temporal gyrus for visual rhyming and fusiform gyrus for auditory spelling. Our findings suggest that the fusiform gyrus processes orthographic word forms, the superior temporal gyrus processes phonologic word forms, and posterior heteromodal regions are involved in the conversion between orthography and phonology.

Adult↗