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At least 793 records · Page 44Linked to original sources
PubMed1997

Buccofacial apraxia and left cerebral haemorrhage.

We examined 33 patients with left intracerebral haemorrhage to investigate the relations to buccofacial apraxia (BFA). BFA was present in 18 cases at 1 month and disappeared in 3 cases and persisted in 15 cases at 6 month from the onset. The existence of BFA seems to be partially dependent the haematoma volume which may cause the organic damage in lenticulate nucleus, insula, posterior limb or internal capsule and anterior portion of paraventricle white matter. All patients with BFA had aphasia (Broca 6, Wernicke 1, Total 10, Amnestic 1). Aphasia of the patients with transient BFA improved as well as the patients without BFA after BFA disappeared. We suspected that improvement or aphasia might be affected by BFA.

Aphasia↗
PubMed2005

22q11.2 deletion syndrome: genetics, neuroanatomy and cognitive/behavioral features keywords.

This paper presents a conceptual review of the genetic underpinnings of 22q11.2 Deletion Syndrome. The neuroanatomical, neuropsychological, behavioral, and psychiatric phenotype associated with 22q11.2 Deletion Syndrome is also explored, including variables that are thought to affect symptom expression. The history of the deletion syndrome is described, and future directions for continued research are discussed.

Achievement↗
PubMed2000

Language abilities of 8-year-old preterm children among the northern Finland 1-year birth cohort for 1985-1986.

The language abilities of 42 8-year-old preterm children with birth weight < 1,750 g from a 1-year birth cohort in northern Finland was studied with four different language tests. Control children from the same birth cohort matched individually with their preterm pairs for age, sex, twinship, mother's education, place of residence, birth order and family type were also studied. In psycholinguistic test, auditory skills did not differ between the preterm and the full-term groups. Nor did any other linguistic subtest differentiate between the groups. Instead, the preterm children scored significantly poorer than their controls in visual subtests. The study also showed that the poor performance in visual tests was associated with neonatal morbidity, namely neonatal infections, need for continuous positive airway pressure (CPAP) treatment and patent ductus arteriosus (PDA). When studying the language abilities of preterm children, we suggest that qualitative methods should be used to analyse linguistic skills. We recommend versatile follow-up of preterm children until school age.

Catchment Area, Health↗
PubMed2001

Cortical mechanism for the visual guidance of hand grasping movements in the monkey: A reversible inactivation study.

Picking up an object requires two basic motor operations: reaching and grasping. Neurophysiological studies in monkeys have suggested that the visuomotor transformations necessary for these two operations are carried out by separate parietofrontal circuits and that, for grasping, a key role is played by a specific sector of the ventral premotor cortex: area F5. The aim of the present study was to test the validity of this hypothesis by reversibly inactivating area F5 in monkeys trained to grasp objects of different shape, size and orientation. In separate sessions, the hand field of the primary motor cortex (area F1 or area 4) was also reversibly inactivated. The results showed that after inactivation of area F5 buried in the bank of the arcuate sulcus (the F5 sector where visuomotor neurones responding to object presentation are located), the hand shaping preceding grasping was markedly impaired and the hand posture was not appropriate for the object size and shape. The monkeys were eventually able to grasp the objects, but only after a series of corrections made under tactile control. With small inactivations the deficits concerned the contralesional hand, with larger inactivations the ipsilateral hand as well. In addition, there were signs of peripersonal neglect in the hemispace contralateral to the inactivation site. Following inactivation of area F5 lying on the cortical convexity (the F5 sector where visuomotor neurones responding to action observation, 'mirror neurones', are found) only a motor slowing was observed, the hand shaping being preserved. The inactivation of the hand field of area F1 produced a severe paralysis of contralateral finger movements with hypotonia. The results of this study indicate the crucial role of the ventral premotor cortex in visuomotor transformations for grasping movements. More generally, they provide strong support for the notion that distal and proximal movement organization relies upon distinct cortical circuits. Clinical data on distal movement deficits in humans are re-examined in the light of the present findings.

Animals↗
PubMed2001

Unilateral spatial neglect.

Unilateral spatial neglect is a complex, but fascinating, deficit in attention that may occur following stroke. The phrase "unilateral spatial neglect" belies the complex mixture of disorders in representational memory, hypokinesia in the opposite hemispace, and inattention to sensory stimuli in the opposite hemispace. Unilateral spatial neglect occurs as a result of damage to the posterior parietal cortex, frontal lobe, cingulate gyrus, striatum, thalamus, or specific brain-stem nuclei. This neural network for attention is an excellent example of how different anatomic areas work together to produce a specific behavior. Traditional treatment strategies for USN have focused on training attention in the left hemispace using a variety of techniques, including sensory awareness, visual scanning, and spatial organization. Recently, additional treatment strategies have emerged that focus on representational aspects of brain functioning. These strategies have included visual and movement imagery,30 manipulation of sensory input that conveys perception of the head in space, and manipulation of visual input using prisms and eye patches. The complex nature of USN provides numerous directions for future research. Continued research will play a pivotal role in devising effective treatment strategies for patients with USN.

Attention↗
PubMed2001

Attentive and preattentive processing in narcolepsy as revealed by event-related potentials (ERPs).

Narcolepsy is a neurological disorder, characterised by excessive daytime sleepiness, sleep attacks, cataplexy and abnormal manifestations of rapid eye movement sleep. Recent studies suggest that neuropsychological impairments in narcolepsy may include memory and attention deficits due to a monoaminergic or cholinergic transmitter dysfunction. To explore the nature of cognitive problems, the P300 and mismatch negativity (MMN) event-related potentials were investigated in narcoleptic patients and matched controls. Narcoleptics showed significantly increased P300 amplitudes relative to controls, especially at frontal recording sites. While control subjects exhibited typically larger MMN over the right than the left hemisphere, in particular at frontal and central electrodes, narcoleptics did not show this asymmetry. These results are interpreted as possible alterations in cognitive preattentive and attentive processing associated with altered functioning of the prefrontal cortex in narcolepsy.

Acoustic Stimulation↗
PubMedDate not supplied

Comorbidity of central auditory processing disorder and attention-deficit hyperactivity disorder.

UNLABELLED: Research has indicated that children with attention-deficit hyperactivity disorder (ADHD) demonstrate significant difficulty on tasks used to assess central auditory processing skills. These findings have raised the question of whether ADHD and central auditory processing disorder (CAPD) represent a singular disorder. OBJECTIVE: The current study explored the incidence of ADHD in a group of 30 children who met diagnostic criteria for CAPD. METHOD: Consecutive referrals specifically for this project were assessed on a variety of measures. In addition, rating scales were completed by teachers and structured interviews were completed with parents. RESULTS: Results indicate that although the incidence rate of ADHD (50%) in this sample significantly exceeds that found in the normative population (p < .001), not all children with CAPD demonstrated behaviors consistent with diagnostic criteria for ADHD. Furthermore, there was a low incidence of any other behavioral disorder in this sample. In contrast, it was found that the sample as a whole demonstrated impaired language abilities. No significant differences emerged across cognitive, auditory, or language measures. CONCLUSION: This study further supports the need for increased collaboration of those professionals who work with these children given the extent of overlap of language and behavioral difficulties in this sample.

Adolescent↗
PubMed1981

Cognitive interaction after staged callosal section: evidence for transfer of semantic activation.

Sensory and cognitive functions were assessed in a right-handed male before and after partial and complete callosal commissurotomy. After the initial posterior section was made, there was no evidence of interhemispheric sensory transfer, although the left hemisphere did have access to stimulus-related semantic and episodic information from the right hemisphere. After the callosum was completely sectioned, this exchange was no longer observed.

Adult↗
PubMedDate not supplied

Boys with reading disabilities and/or ADHD: distinctions in early childhood.

We examined distinctions in the early childhood characteristics of boys with reading disabilities (RD) and/or attention-deficit/ hyperactivity disorder (ADHD). A four-group mixed design consisting of boys identified at age 11 with reading disabilities only (RD only; n = 46), reading disabilities and ADHD (RD/ADHD; n = 16), ADHD only (n = 20), and a comparison group (n = 281) was utilized. Differences on receptive and expressive language and temperament for ages 3 and 5 were investigated. Analyses indicated that the boys from the RD-only group performed worse on measures of receptive and expressive language. The results also indicated that boys from the RD/ADHD groups consistently performed worse on measures of receptive language and exhibited more behaviors indicative of an undercontrolled temperament. In summary, we suggest that reading disabilities and ADHD represent moderately unique disorders that frequently co-occur and are characterized by distinct developmental pathways.

Attention Deficit Disorder with Hyperactivity↗
PubMedDate not supplied

Working memory in Dutch children with reading- and arithmetic-related LD.

The aim of the two studies presented in this article was to examine working memory performance in Dutch children with various subtypes of learning disabilities. The performance of children with reading disabilities (RD) was compared to that of children with arithmetic disabilities (AD), children with both reading and arithmetic disabilities (RAD), and chronological age-matched controls (CA). Measures covered the phonological loop, the visuospatial sketchpad, and the central executive. In both studies, the children with RD showed no working memory deficits whatsoever. Children with AD showed a single impairment on the task tapping working memory for dynamic visual information. Children with RAD performed lower only on the digit span backward task. The failure to replicate the expected working memory deficits in children with reading-related disabilities is discussed.

Child↗
PubMed1996

Validity of the Auditory Continuous Performance Test in differentiating central processing auditory disorders with and without ADHD.

The use of continuous performance tasks has been examined as a potential measure for clinical/laboratory identification of Attention-deficit/hyperactivity disorder. The present study compared the performance of 30 children, 26 boys and 4 girls ranging in age from 9-0 to 12-11, with central auditory processing disorders (CAPD) who did not meet criteria for coexisting ADHD with the performance of children with CAPD coexisting with ADHD (CAPD/ADHD) on the Auditory Continuous Performance Test (ACPT). In interpreting the results, the variability as well as the actual counts for correct responses and total errors were considered. Results indicated limited potential for the use of the ACPT in the differential diagnosis of ADHD. Implications of the results as well as considerations for future research are discussed.

Attention↗
PubMedDate not supplied

Central auditory processing ability in children with ADHD with and without learning disabilities.

A few studies have shown more central auditory processing deficits in children with attention-deficit/hyperactivity disorder (ADHD) than in nondisabled children. Because these studies failed to screen participants with ADHD for learning disabilities (LD), it is not clear whether these deficits are correlates of ADHD or LD or both. In the present study, the central auditory processing ability of children with ADHD, ADHD with LD, and no disabilities was examined. Results indicated lower central auditory processing ability, and significant correlations between reading and ADHD symptoms and reading and central auditory processing ability in the ADHD with LD group compared with the other two groups. These findings suggest that central auditory processing deficits are more likely to be associated with LD than ADHD.

Attention Deficit Disorder with Hyperactivity↗
PubMed2006

Deviation of eyes and head in acute cerebral stroke.

BACKGROUND: It is a well-known phenomenon that some patients with acute left or right hemisphere stroke show a deviation of the eyes (Prévost's sign) and head to one side. Here we investigated whether both right- and left-sided brain lesions may cause this deviation. Moreover, we studied the relationship between this phenomenon and spatial neglect. In contrast to previous studies, we determined not only the discrete presence or absence of eye deviation with the naked eye through clinical inspection, but actually measured the extent of horizontal eye-in-head and head-on-trunk deviation. In further contrast, measurements were performed early after stroke onset (1.5 days on average). METHODS: Eye-in-head and head-on-trunk positions were measured at the bedside in 33 patients with acute unilateral left or right cerebral stroke consecutively admitted to our stroke unit. RESULTS: Each single patient with spatial neglect and right hemisphere lesion showed a marked deviation of the eyes and the head to the ipsilesional, right side. The average spontaneous gaze position in this group was 46 degrees right, while it was close to the saggital body midline (0 degrees ) in the groups with acute left- or right-sided stroke but no spatial neglect as well as in healthy subjects. CONCLUSION: A marked horizontal eye and head deviation observed approximately 1.5 days post-stroke is not a symptom associated with acute cerebral lesions per se, nor is a general symptom of right hemisphere lesions, but rather is specific for stroke patients with spatial neglect. The evaluation of the patient's horizontal eye and head position thus could serve as a brief and easy way helping to diagnose spatial neglect, in addition to the traditional paper-and-pencil tests.

Acute Disease↗