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"Cato, Allison"
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Executive task-based brain function in children with type 1 diabetes: An observational study
by
Foland-Ross, Lara C.
,
Tong, Gabby
,
Reiss, Allan L.
in
Adolescent
,
Behavioral sciences
,
Biology and Life Sciences
2019
Optimal glycemic control is particularly difficult to achieve in children and adolescents with type 1 diabetes (T1D), yet the influence of dysglycemia on the developing brain remains poorly understood.
Using a large multi-site study framework, we investigated activation patterns using functional magnetic resonance imaging (fMRI) in 93 children with T1D (mean age 11.5 ± 1.8 years; 45.2% female) and 57 non-diabetic (control) children (mean age 11.8 ± 1.5 years; 50.9% female) as they performed an executive function paradigm, the go/no-go task. Children underwent scanning and cognitive and clinical assessment at 1 of 5 different sites. Group differences in activation occurring during the contrast of \"no-go > go\" were examined while controlling for age, sex, and scan site. Results indicated that, despite equivalent task performance between the 2 groups, children with T1D exhibited increased activation in executive control regions (e.g., dorsolateral prefrontal and supramarginal gyri; p = 0.010) and reduced suppression of activation in the posterior node of the default mode network (DMN; p = 0.006). Secondary analyses indicated associations between activation patterns and behavior and clinical disease course. Greater hyperactivation in executive control regions in the T1D group was correlated with improved task performance (as indexed by shorter response times to correct \"go\" trials; r = -0.36, 95% CI -0.53 to -0.16, p < 0.001) and with better parent-reported measures of executive functioning (r values < -0.29, 95% CIs -0.47 to -0.08, p-values < 0.007). Increased deficits in deactivation of the posterior DMN in the T1D group were correlated with an earlier age of T1D onset (r = -0.22, 95% CI -0.41 to -0.02, p = 0.033). Finally, exploratory analyses indicated that among children with T1D (but not control children), more severe impairments in deactivation of the DMN were associated with greater increases in hyperactivation of executive control regions (T1D: r = 0.284, 95% CI 0.08 to 0.46, p = 0.006; control: r = 0.108, 95% CI -0.16 to 0.36, p = 0.423). A limitation to this study involves glycemic effects on brain function; because blood glucose was not clamped prior to or during scanning, future studies are needed to assess the influence of acute versus chronic dysglycemia on our reported findings. In addition, the mechanisms underlying T1D-associated alterations in activation are unknown.
These data indicate that increased recruitment of executive control areas in pediatric T1D may act to offset diabetes-related impairments in the DMN, ultimately facilitating cognitive and behavioral performance levels that are equivalent to that of non-diabetic controls. Future studies that examine whether these patterns change as a function of improved glycemic control are warranted.
Journal Article
Cognitive Functioning in Young Children with Type 1 Diabetes
2014
The aim of this study was to assess cognitive functioning in children with type 1 diabetes (T1D) and examine whether glycemic history influences cognitive function. Neuropsychological evaluation of 216 children (healthy controls, n = 72; T1D, n = 144) ages 4–10 years across five DirecNet sites. Cognitive domains included IQ, Executive Functions, Learning and Memory, and Processing Speed. Behavioral, mood, parental IQ data, and T1D glycemic history since diagnosis were collected. The cohorts did not differ in age, gender or parent IQ. Median T1D duration was 2.5 years and average onset age was 4 years. After covarying age, gender, and parental IQ, the IQ and the Executive Functions domain scores trended lower (both p = .02, not statistically significant adjusting for multiple comparisons) with T1D relative to controls. Children with T1D were rated by parents as having more depressive and somatic symptoms (p < .001). Learning and memory (p = .46) and processing speed (p = .25) were similar. Trends in the data supported that the degree of hyperglycemia was associated with Executive Functions, and to a lesser extent, Child IQ and Learning and Memory. Differences in cognition are subtle in young children with T1D within 2 years of onset. Longitudinal evaluations will help determine whether these findings change or become more pronounced with time. (JINS, 2014, 20, 238–247)
Journal Article
Longitudinal Evaluation of Cognitive Functioning in Young Children with Type 1 Diabetes over 18 Months
by
Reiss, Allan L.
,
Tansey, Michael
,
Mauras, Nelly
in
Blood Glucose
,
Case-Control Studies
,
Child
2016
Objectives: Decrements in cognitive function may already be evident in young children with type 1 diabetes (T1D). Here we report prospectively acquired cognitive results over 18 months in a large cohort of young children with and without T1D. Methods: A total of 144 children with T1D (mean HbA1c: 7.9%) and 70 age-matched healthy controls (mean age both groups 8.5 years; median diabetes duration 3.9 years; mean age of onset 4.1 years) underwent neuropsychological testing at baseline and after 18-months of follow-up. We hypothesized that group differences observed at baseline would be more pronounced after 18 months, particularly in those T1D patients with greatest exposure to glycemic extremes. Results: Cognitive domain scores did not differ between groups at the 18 month testing session and did not change differently between groups over the follow-up period. However, within the T1D group, a history of diabetic ketoacidosis (DKA) was correlated with lower Verbal IQ and greater hyperglycemia exposure (HbA1c area under the curve) was inversely correlated to executive functions test performance. In addition, those with a history of both types of exposure performed most poorly on measures of executive function. Conclusions: The subtle cognitive differences between T1D children and nondiabetic controls observed at baseline were not observed 18 months later. Within the T1D group, as at baseline, relationships between cognition (Verbal IQ and executive functions) and glycemic variables (chronic hyperglycemia and DKA history) were evident. Continued longitudinal study of this T1D cohort and their carefully matched healthy comparison group is planned. (JINS, 2016, 21, 293–302)
Journal Article
A Pilot randomized trial to examine effects of a hybrid closed-loop insulin delivery system on neurodevelopmental and cognitive outcomes in adolescents with type 1 diabetes
2022
Type 1 diabetes (T1D) is associated with lower scores on tests of cognitive and neuropsychological function and alterations in brain structure and function in children. This proof-of-concept pilot study (ClinicalTrials.gov Identifier NCT03428932) examined whether MRI-derived indices of brain development and function and standardized IQ scores in adolescents with T1D could be improved with better diabetes control using a hybrid closed-loop insulin delivery system. Eligibility criteria for participation in the study included age between 14 and 17 years and a diagnosis of T1D before 8 years of age. Randomization to either a hybrid closed-loop or standard diabetes care group was performed after pre-qualification, consent, enrollment, and collection of medical background information. Of 46 participants assessed for eligibility, 44 met criteria and were randomized. Two randomized participants failed to complete baseline assessments and were excluded from final analyses. Participant data were collected across five academic medical centers in the United States. Research staff scoring the cognitive assessments as well as those processing imaging data were blinded to group status though participants and their families were not. Forty-two adolescents, 21 per group, underwent cognitive assessment and multi-modal brain imaging before and after the six month study duration. HbA1c and sensor glucose downloads were obtained quarterly. Primary outcomes included metrics of gray matter (total and regional volumes, cortical surface area and thickness), white matter volume, and fractional anisotropy. Estimated power to detect the predicted treatment effect was 0.83 with two-tailed, α = 0.05. Adolescents in the hybrid closed-loop group showed significantly greater improvement in several primary outcomes indicative of neurotypical development during adolescence compared to the standard care group including cortical surface area, regional gray volumes, and fractional anisotropy. The two groups were not significantly different on total gray and white matter volumes or cortical thickness. The hybrid closed loop group also showed higher Perceptual Reasoning Index IQ scores and functional brain activity more indicative of neurotypical development relative to the standard care group (both secondary outcomes). No adverse effects associated with study participation were observed. These results suggest that alterations to the developing brain in T1D might be preventable or reversible with rigorous glucose control. Long term research in this area is needed.
Children with type 1 diabetes (T1D) are at risk for reduced cognitive ability and atypical brain development. This study shows that brain and cognitive measures can be improved in adolescents with T1D using a semi-automated insulin delivery system.
Journal Article
Managing diabetes in preschool children
by
Cato, Allison
,
Smart, Carmel E
,
Weissberg‐Benchell, Jill
in
Children
,
Diabetes
,
Diabetes mellitus
2017
If pump therapy is not available, multiple daily injections (MDIs), with consideration of use of an injection port, should be used from the onset of diabetes (E). ○ For preschool children using intensive insulin therapy, preprandial administration of bolus insulin given for correction if blood glucose is high and for at least part of the meal is preferable to giving the whole dose during or after the meal (C). ○ Carbohydrate counting is best introduced at onset of diabetes (E). ○ The small insulin doses of preschool children may necessitate diluting insulin for precise dosing (E). ○ Syringes with ½ unit marking and pens with at least ½ unit dosing increments should be used to facilitate more accurate insulin dosing if a pump is not used (or as a back-up to pump use) (E). ○ Continuous glucose monitoring (CGM) can be helpful as an approach to adjusting insulin doses (E). Weight, height (or length if <18 months), and Body Mass Index Standard Deviation Score (or percentiles) should be monitored on growth charts in all children with type 1 diabetes (E). Optimizing glycemic control for children in this age group often requires treatment using strategies that differ from those employed for older children and adolescents with type 1 diabetes. Screening and promotion of optimal health-related quality of life should be regularly undertaken in preschool children with type 1 diabetes as in any child with type 1 diabetes.
Journal Article
Left and right basal ganglia and frontal activity during language generation: Contributions to lexical, semantic, and phonological processes
by
MOORE, ANNA BACON
,
LEONARD, CHRISTIANA M.
,
WIERENGA, CHRISTINA E.
in
Adolescent
,
Adult
,
Basal ganglia
2003
fMRI was used to determine the frontal, basal ganglia, and thalamic
structures engaged by three facets of language generation: lexical
status of generated items, the use of semantic vs. phonological
information during language generation, and rate of generation. During
fMRI, 21 neurologically normal subjects performed four tasks:
generation of nonsense syllables given beginning and ending consonant
blends, generation of words given a rhyming word, generation of words
given a semantic category at a fast rate (matched to the rate of
nonsense syllable generation), and generation of words given a semantic
category at a slow rate (matched to the rate of generating of rhyming
words). Components of a left pre-SMA–dorsal caudate
nucleus–ventral anterior thalamic loop were active during word
generation from rhyming or category cues but not during nonsense
syllable generation. Findings indicate that this loop is involved in
retrieving words from pre-existing lexical stores. Relatively diffuse
activity in the right basal ganglia (caudate nucleus and putamen) also
was found during word-generation tasks but not during nonsense syllable
generation. Given the relative absence of right frontal activity during
the word generation tasks, we suggest that the right basal ganglia
activity serves to suppress right frontal activity, preventing right
frontal structures from interfering with language production. Current
findings establish roles for the left and the right basal ganglia in
word generation. Hypotheses are discussed for future research to help
refine our understanding of basal ganglia functions in language
generation. (JINS, 2003, 9, 1061–1077.)
Journal Article
Assessing the elusive cognitive deficits associated with ventromedial prefrontal damage: A case of a modern-day Phineas Gage
2004
Cognitive deficits following ventromedial prefrontal damage (VM-PFD)
have been elusive, with most studies reporting primarily emotional and
behavioral changes. The present case illustrates the utility of a
process approach to assessing cognitive deficits following VM-PFD. At
age 26, C.D. acquired bilateral VM-PFD, more so in the left frontal
region, following a penetrating head injury. Despite exemplary
premorbid academic and military performances, his subsequent history
suggests dramatic occupational and social changes, reminiscent of
Phineas Gage. In fact, lesion analysis revealed similar structural
damage to that estimated of Gage. C.D.'s scores on the vast
majority of neuropsychological measures were average to superior (e.g.,
Verbal IQ = 119). However, on several new process measures,
particularly those that quantify error rates on multilevel executive
function and memory tasks, C.D. exhibited marked impairments. From his
pattern of deficits, C.D. appeared to sacrifice accuracy for speed and
to adopt liberal response strategies, implicating problems with
cognitive inflexibility, impulsivity, and disinhibition. The current
findings suggest that VM-PFD may be associated with a wider spectrum of
cognitive deficits than previously characterized. (JINS, 2004,
10, 453–465.)
Journal Article
Treatment of naming in nonfluent aphasia through manipulation of intention and attention: A phase 1 comparison of two novel treatments
by
MOORE, ANNA BACON
,
RODRIGUEZ, AMY
,
WIERENGA, CHRISTINA E.
in
Accuracy
,
Aged
,
Analysis of Variance
2007
Twenty-three chronic nonfluent aphasia patients with moderate or
severe word-finding impairments and 11 with profound word-finding
impairments received two novel picture-naming treatments. The intention
treatment initiated picture-naming trials with a complex left-hand
movement and was designed to enhance right frontal participation during
word retrieval. The attention treatment required patients to view visual
stimuli for picture-naming trials in their left hemispace and was designed
to enhance right posterior perisylvian participation during word
retrieval. Because the intention treatment addressed action mechanisms and
nonfluent aphasia reflects difficulty initiating or maintaining action
(i.e., language output), it was hypothesized that intention component of
the treatment would enhance re-acquisition of picture naming more than the
attention component. Patients with moderate and severe word-finding
impairment showed gains with both treatments but greater incremental
improvement from one treatment phase to the next with the intention than
the attention treatment. Thus, the hypothesis that intention component
would be a more active constituent than the attention component was
confirmed for these patients. Patients with profound word-finding
impairment showed some improvement with both treatments but no
differential effects for the intention treatment. Almost all patients who
showed treatment gains on either treatment also demonstrated
generalization from trained to untrained items. (JINS, 2007,
13, 582–594.)
Journal Article
Impact of dysglycemia and obesity on the brain in adolescents with and without type 2 diabetes: A pilot study
2022
Objective Both diabetes and obesity can affect the brain, yet their impact is not well characterized in children with type 2 (T2) diabetes and obesity. This pilot study aims to explore differences in brain function and cognition in adolescents with T2 diabetes and obesity and nondiabetic controls with obesity and lean controls. Research design and methods Participants were 12‐17 years old (5 T2 diabetes with obesity [mean HgbA1C 10.9%], 6 nondiabetic controls with obesity and 10 lean controls). Functional MRI (FMRI) during hyperglycemic/euglycemic clamps was performed in the T2 diabetes group. Results When children with obesity, with and without diabetes, were grouped (mean BMI 98.8%), cognitive scores were lower than lean controls (BMI 58.4%) on verbal, full scale, and performance IQ, visual‐spatial and executive function tests. Lower scores correlated with adiposity and insulin resistance but not HgbA1C. No significant brain activation differences during task based and resting state FMRI were noted between children with obesity (with or without diabetes) and lean controls, but a notable effect size for the visual‐spatial working memory task and resting state was observed. Conclusions In conclusion, our pilot study suggests that obesity, insulin resistance, and dysglycemia may contribute to relatively poorer cognitive function in adolescents with T2 diabetes and obesity. Further studies with larger sample size are needed to assess if cognitive decline in children with obesity, with and without T2 diabetes, can be prevented or reversed.
Journal Article
Neural substrates of object identification: Functional magnetic resonance imaging evidence that category and visual attribute contribute to semantic knowledge
by
LEONARD, CHRISTIANA M.
,
WIERENGA, CHRISTINA E.
,
GOPINATH, KAUNDINYA
in
Adult
,
Alzheimer's disease
,
Analysis of Variance
2009
Recent findings suggest that neural representations of semantic knowledge contain information about category, modality, and attributes. Although an object’s category is defined according to shared attributes that uniquely distinguish it from other category members, a clear dissociation between visual attribute and category representation has not yet been reported. We investigated the contribution of category (living and nonliving) and visual attribute (global form and local details) to semantic representation in the fusiform gyrus. During functional magnetic resonance imaging (fMRI), 40 adults named pictures of animals, tools, and vehicles. In a preliminary study, identification of objects in these categories was differentially dependent on global versus local visual feature processing. fMRI findings indicate that activation in the lateral and medial regions of the fusiform gyrus distinguished stimuli according to category, that is, living versus nonliving, respectively. In contrast, visual attributes of global form (animals) were associated with higher activity in the right fusiform gyrus, while local details (tools) were associated with higher activity in the left fusiform gyrus. When both global and local attributes were relevant to processing (vehicles), cortex in both left and right medial fusiform gyri was more active than for other categories. Taken together, results support distinctions in the role of visual attributes and category in semantic representation. (JINS, 2009, 15, 169–181.)
Journal Article