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Jeffrey Schatz

Publications and source records attributed to Jeffrey Schatz.

10 recordsLinked to original sources

Sickle cell disease as a neurodevelopmental disorder.

Sickle cell disease (SCD) is a blood disorder; however, the central nervous system (CNS) is one of the organs frequently affected by the disease. Brain disease can begin early in life and often leads to neurocognitive dysfunction. Approximately one-fourth to one-third of children with SCD have some form of CNS effects from the disease, which typically manifest as deficits in specific cognitive domains and academic difficulties. We discuss SCD as a neurodevelopmental disorder by reviewing the mechanisms of neurological morbidity in SCD, the timing of these mechanisms, the types of cognitive and behavioral morbidity that is typical, and the interaction of social-environmental context with disease processes. The impact of the disease on families shares many features similar to other neurodevelopmental disorders; however, social-environmental factors related to low socioeconomic status, worry and concerns about social stigma, and recurrent, unpredictable medical complications can be sources of relatively higher stress in SCD. Greater public awareness of the neurocognitive effects of SCD and their impact on child outcomes is a critical step toward improved treatment, adaptation to illness, and quality of life.

Anemia, Sickle Cell↗

Decreased corpus callosum size in sickle cell disease: relationship with cerebral infarcts and cognitive functioning.

We assessed midsagittal corpus callosum size in sickle cell disease (SCD) and its relationship to lesion volume, lesion location, and cognitive functioning. Twenty-eight children with SCD and 16 demographic controls completed magnetic resonance imaging (MRI) and neuropsychological testing. Corpus callosum (CC) size was smaller for children with silent infarcts (n = 8) or overt stroke (n = 8) than for those without visible infarcts (n = 12) or control participants. Lesion volume was a robust predictor of IQ and other cognitive scores; total CC size did not typically add explanatory power for these measures. The size of the rostral body of the CC, however, independently predicted measures of distractibility, speeded production, and working memory. Posterior CC size was also decreased among many of the children with SCD, even in the absence of visible infarcts in this region. Brain morphology appears to provide additional information about SCD-related effects on the brain above and beyond visible infarcts.

Anemia, Sickle Cell↗

Short-term memory in children with sickle cell disease: executive versus modality-specific processing deficits.

Prior research has identified a number of areas of cognitive deficit among children with sickle cell disease (SCD), including decrements in memory span and working memory. The present study examined short-term memory span and working memory performance among children with SCD (n = 25) and demographically matched comparison children (n = 25) using digit span, spatial span, and the self-ordered pointing test. Children with SCD showed difficulties only for digit span-backward. Additional cognitive ability measures administered indicated auditory processing was an area of deficit related to digit span-backward performance. The study suggests that modality specific deficits are one factor in short-term memory span for children with SCD. The cause of this deficit is unclear, but may involve both central and peripheral components of auditory processing.

Adolescent↗

Visual attention in long-term survivors of leukemia receiving cranial radiation therapy.

The effect of cranial radiation therapy (CRT) on visual attention was examined in long-term survivors of childhood acute lymphoblastic leukemia (ALL) compared to peers with no history of ALL (n = 24) using a cued orienting task and a global-local task. ALL participants treated with CRT (n = 13) demonstrated an increased cost in response time with invalid spatial orienting cues and inefficient shifts of attention across hierarchical levels. ALL participants treated only with chemotherapy (n = 8) showed performance similar to the non-ALL comparison group. Participants with exposure to CRT early in life appeared to largely account for the attention deficits, and showed particular difficulties with shifting attention from the local level of stimuli to the global level. The data are consistent with prior reports emphasizing attention deficits following CRT, and suggest that attention shifting may be particularly affected by CRT early in life.

Adolescent↗

Asymmetries in visual-spatial processing following childhood stroke.

The authors compared hemisphere-based and cognitive-domain-based hypotheses for visual-spatial deficits in children with stroke (n = 33) and children without stroke (n = 43). Children with unilateral left (n = 14) or right (n = 7) injury showed less efficient search for the visual field contralateral to their injury. Right-hemisphere injury was associated with deficient global-level processing and coordinate spatial judgments. Left-hemisphere injury resulted in relatively intact local versus global processing and categorical versus coordinate judgments. Bilateral injury (n = 12) resulted in disruption of visual search across visual fields and relative deficits in global-level processing and coordinate spatial judgments. Recovery of visual-spatial processing in children following childhood stroke is task specific. Certain visual-spatial functions typically mediated by the left hemisphere appear less vulnerable to disruption.

Adolescent↗

Brief report: Academic attainment in children with sickle cell disease.

OBJECTIVE: To examine the impact of sickle cell disease (SCD) on academic attainment; the relation between academic attainment and achievement in SCD; and determinants of attainment in SCD. METHODS: Children with SCD and demographically matched peers were compared on academic attainment. Hematocrit, illness frequency, cognitive ability, and socioeconomic status were used to model the predictors of attainment problems. RESULTS: Attainment problems were more frequent in children with SCD (> or =31% vs. 14%). A significant number of children showed difficulties with only attainment or academic achievement. Cognitive ability was a strong predictor of both academic outcome measures. Illness-related school absences predicted academic attainment but not achievement. CONCLUSIONS: Academic attainment is affected by SCD. Tests of academic achievement are meaningful predictors of functional impairments for children with SCD; however, school outcomes are best evaluated with both achievement and attainment measures.

Achievement↗

Interactions of biomedical and environmental risk factors for cognitive development: a preliminary study of sickle cell disease.

Sickle cell disease (SCD) is associated with a number of biopsychosocial risk factors for cognitive development. Understanding how these risk factors may interact is important for developing interventions for cognitive functioning. The authors assessed the cognitive abilities of children with SCD (n = 50) and related their performance to anemia severity, socioeconomic status (SES), and their interaction. Demographically matched peers without SCD (n = 36) served as a comparison group. Four areas of cognitive weakness were identified among children with SCD: general cognitive ability, crystallized ability, short-term memory, and processing speed. Anemia severity predicted general cognitive ability, crystallized ability, and processing speed. Interactions between anemia severity and SES were found for general cognitive ability and short-term memory. Disease effects in SCD appear to vary depending on the child's level of socioenvironmental risk. Biomedical interventions to benefit cognitive functioning may have different effects depending on whether additional socioenvironmental risk factors are present.

Adolescent↗

Level-repetition effects in hierarchical stimulus processing: timing and location of cortical activity.

The specific mechanisms that underlie repetition priming effects are only partly understood. We examined the timing and extent of brain activity in response to level-repeated and level-shifted conditions during hierarchical stimulus processing. A response cost in behavioral reaction times was evident for level-shifted compared to level-repeated conditions. Larger event-related potentials amplitudes for level-shifted conditions were evident over occipital scalp regions for an early component peaking at 132 ms post-stimulus onset. A negative potential over posterior temporal electrodes that peaked at 204 ms showed asymmetries in amplitudes that were consistent with lateralized differences in global and local level processing. A positive potential peaking at 290 ms also showed differences between level-repeated and level-shifted conditions over left parietal and left posterior temporal scalp regions. The study demonstrates cortical activity related to repetition priming for both local and global level targets. Early sensory ("P1") and later cortical processing can be affected by the need to shift attention across hierarchical levels. The results support the existence of multiple processes underlying level-repetition effects.

Adolescent↗

Cognitive functioning in children with sickle cell disease: a meta-analysis.

OBJECTIVE: To establish whether sickle cell disease (SCD) affects cognitive functioning in children with no evidence of cerebral infarction. METHODS: We conducted a meta-analysis of studies of cognition in SCD to determine the size of any statistical difference between children with SCD and controls. Methodological factors were evaluated according to the size and frequency of group differences. RESULTS: There were small but reliable decrements in cognitive functioning on IQ measures (4.3-point difference overall). The most methodologically rigorous studies showed a highly similar pattern. Sampling issues associated with the effect size for IQ were identified. Measures of specific abilities appear more sensitive than IQ scores to cognitive decrements in SCD. CONCLUSIONS: SCD is associated with cognitive effects even in the absence of cerebral infarction. The causes of this cognitive decrement may include direct effects of SCD on brain function or indirect effects of chronic illness.

Adolescent↗

Lesion burden and cognitive morbidity in children with sickle cell disease.

The effect of increased tissue injury in children with sickle cell disease and silent cerebral infarcts is not known. We determined the relationship between the extent of injury and IQ scores in children with silent cerebral infarcts. Participants were 27 children with sickle cell disease who had received magnetic resonance imaging (MRI). Children were divided into three groups: group 1, small lesion volume (n = 9, < 6.8 cm3); group 2, large lesion volume (n = 9; > 6.8 cm3); and group 3, no cerebral infarcts (n = 9). The Wechsler Full-Scale IQ was significantly lower for group 2 (mean = 76.1) when compared with group 1 (mean = 87.7) or group 3 (mean = 89.9). In children with silent cerebral infarcts, large tissue loss is associated with lower Wechsler Full-Scale IQ and small tissue loss is associated with no apparent change in IQ compared with children with no cerebral infarcts. The progressive accumulation of silent infarcts may lead to poorer intellectual functioning.

Adolescent↗