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. 2020 Mar;129(3):207-212.
doi: 10.1016/j.ymgme.2019.12.014. Epub 2020 Jan 10.

Evaluation of neurocognitive function of prefrontal cortex in ornithine transcarbamylase deficiency

Afrouz Anderson  1 , Andrea Gropman  2 , Cynthia Le Mons  3 , Constantine Stratakis  1 , Amir Gandjbakhche  4
Affiliations

Evaluation of neurocognitive function of prefrontal cortex in ornithine transcarbamylase deficiency

Afrouz Anderson et al. Mol Genet Metab. 2020 Mar.

Abstract

Hyperammonia due to ornithine transcarbamylase deficiency (OTCD) can cause a range of deficiencies in domains of executive function and working memory. Only a few fMRI studies have focused on neuroimaging data in a population with OTCD. Yet, there is a need for monitoring the disease progression and neurocognitive function in this population. In this study, we used a non-invasive neuroimaging technique, functional Near Infrared Spectroscopy (fNIRS), to examine the hemodynamics of prefrontal cortex (PFC) based on neural activation in an OTCD population. Using fNIRS, we measured the activation in PFC of the participants while performing the Stroop task. Behavioral assessment such as reaction time and correct response were recorded. We investigated the difference in behavioral measures as well as brain activation in left and right PFC in patients with OTCD and controls. Results revealed a distinction in left PFC activation between controls and patients with OTCD, where control subjects showed higher task related activation increase. Subjects with OTCD also exhibited bilateral increase in PFC activation. There was no significant difference in response time or correct response between the two groups. Our findings suggest the alterations in neurocognitive function of PFC in OTCD compared to the controls despite the behavioral profiles exhibiting no such differences. This is a first study using fNIRS to examine a neurocognitive function in OTCD population and can provide a novel insight into the screening of OTCD progression and examining neurocognitive changes.

Keywords: Brain activation; Cerebral hemodynamics; Executive function; Functional near infrared spectroscopy; Metabolic disorder; Prefrontal cortex; Stroop task; Urea cycle disorder.

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Figures

Figure 1.
Figure 1.
Stroop Paradigm Task design. Blocks of congruent and incongruent were displayed on the screen with the rest blocks in between, where during congruent condition the color and word were matching while in incongruent condition the color and words were different.
Figure 2.
Figure 2.
A diagram showing NIR light (photons) passing through cortical region from location of source, while the backscattered light is detected at the detector site.
Figure 3.
Figure 3.
Schematic of fNIRS headband sensor containing 4 sources and 10 detectors with total of 16 channel combination
Figure 4.
Figure 4.
a) Bar graph of reaction time during performance of congruent and incongruent task based on diagnosis. There was no significant difference between OTCD and control subjects based on the reaction time. b) Bar graph of correct response during performance of congruent and incongruent task in control and OTCD group
Figure 5.
Figure 5.
Activation level in Left and Right prefrontal cortex (PFC) in controls and subjects with OTCD, where control group showed higher activation in Left PFC compared to the OTCD group.
Figure 6.
Figure 6.
Map of activation in prefrontal cortex (PFC) in a) control subjects and b) subjects with OTCD, where control group showed higher Stroop Interference activation compared to OTCD subjects in left PFC, while no activation difference was observed in right PFC.
Figure 7.
Figure 7.
Correlation between left and right prefrontal cortex (PFC) activation in control and subjects with OTCD, where compared to controls, subjects with OTCD showed bilateral increase in level of activation.
See this image and copyright information in PMC

References

    1. Gropman AL, Summar M, and Leonard JV, Neurological implications of urea cycle disorders. Journal of inherited metabolic disease, 2007. 30(6): p. 865–879. - PMC - PubMed
    1. Gropman AL, et al., Diffusion tensor imaging detects areas of abnormal white matter microstructure in patients with partial ornithine transcarbamylase deficiency. AJNR. American journal of neuroradiology, 2010. 31(9): p. 1719–1723. - PMC - PubMed
    1. Gropman AL, et al., 1H MRS identifies symptomatic and asymptomatic subjects with partial ornithine transcarbamylase deficiency. Molecular genetics and metabolism, 2008. 95(1–2): p. 2130. - PMC - PubMed
    1. Gropman AL and Batshaw ML, Cognitive outcome in urea cycle disorders. Molecular genetics and metabolism, 2004. 81: p. 58–62. - PubMed
    1. Gyato K, et al., Metabolic and neuropsychological phenotype in women heterozygous for ornithine transcarbamylase deficiency. Annals of Neurology, 2004. 55(1): p. 80–86. - PubMed

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