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E Temple

Publications and source records attributed to E Temple.

9 recordsLinked to original sources

Relations between the neural bases of dynamic auditory processing and phonological processing: evidence from fMRI.

Functional magnetic resonance imaging (fMRI) was used to examine how the brain responds to temporal compression of speech and to determine whether the same regions are also involved in phonological processes associated with reading. Recorded speech was temporally compressed to varying degrees and presented in a sentence verification task. Regions involved in phonological processing were identified in a separate scan using a rhyming judgment task with pseudowords compared to a lettercase judgment task. The left inferior frontal and left superior temporal regions (Broca's and Wernicke's areas), along with the right inferior frontal cortex, demonstrated a convex response to speech compression; their activity increased as compression increased, but then decreased when speech became incomprehensible. Other regions exhibited linear increases in activity as compression increased, including the middle frontal gyri bilaterally. The auditory cortices exhibited compression-related decreases bilaterally, primarily reflecting a decrease in activity when speech became incomprehensible. Rhyme judgments engaged two left inferior frontal gyrus regions (pars triangularis and pars opercularis), of which only the pars triangularis region exhibited significant compression-related activity. These results directly demonstrate that a subset of the left inferior frontal regions involved in phonological processing is also sensitive to transient acoustic features within the range of comprehensible speech.

Adult↗

Disrupted neural responses to phonological and orthographic processing in dyslexic children: an fMRI study.

Developmental dyslexia, characterized by difficulty in reading, has been associated with phonological and orthographic processing deficits. fMRI was performed on dyslexic and normal-reading children (8-12 years old) during phonological and orthographic tasks of rhyming and matching visually presented letter pairs. During letter rhyming, both normal and dyslexic reading children had activity in left frontal brain regions, whereas only normal-reading children had activity in left temporo-parietal cortex. During letter matching, normal-reading children showed activity throughout extrastriate cortex, especially in occipito-parietal regions, whereas dyslexic children had little activity in extrastriate cortex during this task. These results indicate dyslexia may be characterized in childhood by disruptions in the neural bases of both phonological and orthographic processes important for reading.

Child↗

Disruption of the neural response to rapid acoustic stimuli in dyslexia: evidence from functional MRI.

The biological basis for developmental dyslexia remains unknown. Research has suggested that a fundamental deficit in dyslexia is the inability to process sensory input that enters the nervous system rapidly and that deficits in processing rapid acoustic information are associated with impaired reading. Functional magnetic resonance imaging (fMRI) was used to identify the brain basis of rapid acoustic processing in normal readers and to discover the status of that response in dyslexic readers. Normal readers showed left prefrontal activity in response to rapidly changing, relative to slowly changing, nonlinguistic acoustic stimuli. Dyslexic readers showed no differential left frontal response. Two dyslexic readers participated in a remediation program and showed increased activity in left prefrontal cortex after training. These fMRI results identify left prefrontal regions as normally being sensitive to rapid relative to slow acoustic stimulation, insensitive to the difference between such stimuli in dyslexic readers, and plastic enough in adulthood to develop such differential sensitivity after intensive training.

Acoustic Stimulation↗

Microstructure of temporo-parietal white matter as a basis for reading ability: evidence from diffusion tensor magnetic resonance imaging.

Diffusion tensor magnetic resonance imaging (MRI) was used to study the microstructural integrity of white matter in adults with poor or normal reading ability. Subjects with reading difficulty exhibited decreased diffusion anisotropy bilaterally in temporoparietal white matter. Axons in these regions were predominantly anterior-posterior in direction. No differences in T1-weighted MRI signal were found between poor readers and control subjects, demonstrating specificity of the group difference to the microstructural characteristics measured by diffusion tensor imaging (DTI). White matter diffusion anisotropy in the temporo-parietal region of the left hemisphere was significantly correlated with reading scores within the reading-impaired adults and within the control group. The anisotropy reflects microstructure of white matter tracts, which may contribute to reading ability by determining the strength of communication between cortical areas involved in visual, auditory, and language processing.

Adult↗

Effects of aerobic exercise on serum leptin levels in obese women.

It has been demonstrated that leptin concentrations in obese patients may be altered by weight loss. We examined the effects of a 9-week aerobic exercise program on serum leptin concentrations in overweight women (20-50% above ideal body mass) under conditions of weight stability. Sixteen overweight women, mean (SE) age 42.75 (1.64) years, comprised the exercise group which adhered to a supervised aerobic exercise program. A graded exercise treadmill test was conducted before and after the exercise program to determine maximal oxygen uptake (VO2max) using open-circuit spirometry. The women demonstrated improved aerobic fitness (VO2max increased 12.29%), however, body fat and the body mass index did not change significantly [42.27 (1.35)-41.87 (1.33)%]. Fourteen women, age 40.57 (2.80) years, did not exercise over the same time period and served as a control group. Serum leptin levels were not significantly altered for either the exercise [28.00 (2.13)-31.04 (2.71) ng x ml(-1)] or the control group [33.24 (3.78)-34.69 (3.14) ng x mg(-1)]. The data indicate that 9 weeks of aerobic exercise improves aerobic fitness, but does not affect leptin concentrations in overweight women.

Adult↗

Plasma vitamin A and E in preterm babies fed on breast milk or formula milk with or without long-chain polyunsaturated fatty acids.

Plasma vitamin A and E, the antioxidant nutrients copper and zinc, and magnesium were investigated in preterm babies. They were fed on their own mother's breast milk, or a formula with, or without, AA and DHA. Vitamin A (2.4 mg/d) and E (15 mg/d) supplements were also given. Vitamin A and E levels of most of the babies were sub-optimal at birth. The mean concentrations of vitamin E increased in all the groups by the expected date of delivery (EDD) (p < 0.001). Those fed on their mother's breast milk had the highest value compared with the other groups (p < 0.001). There was an increase in the mean level of vitamin A (p > 0.05) and copper (p < 0.05) and a decrease in zinc (p < 0.05) between birth and EDD. Concentrations of the two vitamins were not different (p > 0.05) between the babies fed on the formula with, and without, AA and DHA. It is concluded that the amount of AA and DHA incorporated in the formula milk did not adversely influence the plasma vitamin A and E of the babies.

Anthropometry↗

Brain mechanisms of quantity are similar in 5-year-old children and adults.

Both 5-year-old children and adults determine the quantity of a number by the use of a similar parietal lobe mechanism. Event related potentials indicate that input from Arabic digits and from dot patterns reach areas involved in determining quantity about 200 ms after input. However, voluntary key presses indicating the relation of the input to the quantity five take almost three times as long in children. The ability to trace the networks of brain areas involved in the learning of school subjects should aid in the design and testing of educational methods.

Adult↗

Repression of a mutant derivative of the pRE promoter of bacteriophage lambda by its activator, CII.

A 2-bp insertion between the -10 and -35 regions of the pRE promoter of bacteriophage lambda reverses the effect of the activator protein, CII, on transcription from pRE in vitro. The mutant promoter is weakly constitutive in the absence of cII protein and repressed in its presence. This is in sharp contrast to wild-type pRE which is inactive in the absence of cII protein and stimulated at least 1000-fold in its presence (Shih and Gussin, 1984a; McClure and Hoopes, 1985). These effects are explained by the creation of a new -35 region with weak homology to the -35 consensus sequence for Escherichia coli promoters, and by the altered spatial relationship between the -35 region and the CII-binding site. This interpretation was confirmed by analysis of double mutants containing known cy (pRE) mutations together with the 2-bp insertion. Insertion of 4 bp or deletion of 2 bp completely inactivates pRE in the presence or absence of cII protein, again indicating that activation is dependent upon proper spacing between the -35 region and the transcription start point.

Bacteriophage lambda↗