Biomedical subjects

Katherine Mathews

Publications and source records attributed to Katherine Mathews.

5 recordsLinked to original sources

PubMed2005

Prefrontal and executive attention network lesions and the development of attention-deficit/hyperactivity symptomatology.

OBJECTIVE: To investigate the association between focal stroke lesions of Posner's executive attention network and a specific region of interest in the frontal lobes (orbital frontal and mesial frontal) and either attention-deficit/hyperactivity disorder (ADHD) or traits of the disorder (ADHD symptomatology). METHOD: Twenty-nine children with focal stroke lesions were studied with standardized psychiatric assessments and anatomical brain magnetic resonance imaging. The pattern of lesion overlap in subjects with ADHD symptomatology was determined. RESULTS: Fifteen of 28 subjects with no prestroke ADHD were diagnosed with ADHD symptomatology at the time of assessment. The extent of lesions within the executive attention network was marginally related to ADHD symptomatology (p = .088; effect size = 0.66), whereas the extent of lesions in the specific frontal region of interest was significantly related to ADHD symptomatology (p = .040; effect size = 0.82). CONCLUSIONS: Lesions within Posner's executive attention network and its orbital frontal connections may be linked to important mechanisms in the expression of ADHD symptomatology after childhood stroke. These findings are consistent with functional and structural imaging findings in studies of idiopathic ADHD.

Attention Deficit Disorder with Hyperactivity↗

PubMed2004

Attention function after childhood stroke.

We investigated attentional outcome after childhood stroke and orthopedic diagnosis in medical controls. Twenty-nine children with focal stroke lesions and individually matched children with clubfoot or scoliosis were studied with standardized attention and neuroimaging assessments. Stroke lesions were quite varied in location and commonly involved regions implicated in Posner's model of attention networks. Children with stroke lesions performed significantly more poorly regarding attention function compared with controls. Performance on the Starry Night, a test demanding alerting and sensory-orienting but not executive attention function, was significantly associated with lesion size in the alerting and sensory-orienting networks but not the executive attention network. Furthermore, earlier age at lesion acquisition was significantly associated with poorer attention function even when lesion size was controlled. These findings support the theory of dissociable networks of attention and add to evidence from studies of children with diffuse and focal brain damage that early insults are associated with worse long-term outcomes in many domains of neuropsychological function. In addition, these results may provide clues towards the understanding of mechanisms underlying attention in children.

Adolescent↗

PubMed2003

Attention deficit hyperactivity disorder and neurocognitive correlates after childhood stroke.

We investigated the frequency and neurocognitive correlates of attention deficit hyperactivity disorder and traits of this disorder (ADHD/Traits) after childhood stroke and orthopedic diagnosis in medical controls. Twenty-nine children with focal stroke lesions and individually matched children with clubfoot or scoliosis were studied with standardized psychiatric, intellectual, academic, adaptive, executive, and motivation function assessments. Lifetime ADHD/Traits were significantly more common in stroke participants with no prestroke ADHD than in orthopedic controls (16/28 vs. 7/29; Fisher's Exact p < .02). Lifetime ADHD/Traits in the orthopedic controls occurred exclusively in males with clubfoot (7/13; 54%). Participants with current ADHD/Traits functioned significantly worse (p < .005) than participants without current ADHD/Traits on all outcome measures. Within the stroke group, current ADHD/Traits was associated with significantly lower verbal IQ and arithmetic achievement (p < .04), more nonperseverative errors (p < .005), and lower motivation (p < .004). A principal components analysis of selected outcome variables significantly associated with current ADHD/Traits revealed "impaired neurocognition" and "inattention-apathy" factors. The latter factor was a more consistent predictor of current ADHD/Traits in regression analyses. These findings suggest that inattention and apathy are core features of ADHD/Traits after childhood stroke. This association may provide clues towards the understanding of mechanisms underlying the syndrome.

Adaptation, Psychological↗

PubMed2002

Psychiatric disorders after childhood stroke.

OBJECTIVES: To determine the rate, types, and correlates of psychiatric disorder (PD) following stroke and orthopedic disorders in children and adolescents. METHOD: Children aged 5 to 19 were assessed. The study used a cross-sectional design that compared 29 stroke subjects with 29 congenital clubfoot or scoliosis subjects. Assessments of psychiatric status; cognitive, adaptive, academic, and family functioning; family psychiatric history; neuroimaging; and neurological status were conducted. The main outcome measure was a current PD not present before the stroke or orthopedic disorder. RESULTS: Poststroke PD occurred significantly more often than postorthopedic diagnosis PD (17/29 [59%] versus 4/29 [14%], p < or =.001). Subjects with ongoing poststroke PD had significantly more impaired intellectual and adaptive functioning, higher intensity family psychiatric history scores, and tended toward higher neurological severity index scores, but they were not different regarding lesion volume or family functioning compared with stroke subjects without PD. Regression analyses showed that neurological severity and family psychiatric history independently contributed significantly to predicting PD. CONCLUSIONS: The data suggest that there are significant biopsychosocial correlates of PD in children with focal neurological lesions. These include a relatively abnormal neurological exam, lower IQ, and increased family psychopathology.

Adolescent↗

PubMed2002

Putamen lesions and the development of attention-deficit/hyperactivity symptomatology.

OBJECTIVE: To investigate the association between focal stroke lesions of the putamen and either attention-deficit/hyperactivity disorder or traits of the disorder (ADHD/Traits). METHOD: Twenty-five children with focal stroke lesions were studied with standardized psychiatric assessments and anatomic brain magnetic resonance imaging. The pattern of lesion overlap in subjects with ADHD/Traits was determined. RESULTS: Fifteen of 25 subjects had ADHD/Traits. The densest area of overlapping lesions (n = 7) in subjects with ADHD/Traits included the posterior ventral putamen. The median lesion volume was 9.7 cm3, and the distribution was highly skewed. Lesion volume was not associated with ADHD/Traits. Therefore the following analyses focused on the 13 subjects with lesions < 10 cm3: ADHD/Traits were exhibited in 6/7 subjects with putamen lesionsversus 2/6 with no putamen lesions (Fisherexacttestp= .1). Half (4/8) of the subjects with ADHD/Traits had overlapping lesions encompassing the posterior ventral putamen. None of the 5 subjects without ADHD/Traits had lesions in this empirically derived region of interest (Fisher exact test p = .1). CONCLUSIONS: Lesions within the dopamine-rich ventral putamen, which is part of the ventral or limbic striatum, tended to increase the risk of ADHD/Traits. ADHD/Traits may therefore be a disinhibition syndrome associated with dysfunction in this cortical-striato-thalamocortical loop.

Adolescent↗