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Neuromagnetic vistas into typical and atypical development of frontal lobe functions.

Taylor MJ, Doesburg SM, Pang EW - Front Hum Neurosci (2014)

Bottom Line: There are several challenges for MEG developmental studies: to design tasks appropriate to capture the neurodevelopmental trajectory of these cognitive functions, and to develop appropriate analysis strategies to capture various aspects of neuromagnetic frontal lobe activity.The studies include facial emotional processing, inhibition, visual short-term memory, speech production, and resting-state networks.We also discuss the challenges of testing young children in the MEG and the development of age-appropriate technologies and paradigms.

View Article: PubMed Central - PubMed

Affiliation: Department of Diagnostic Imaging, Hospital for Sick Children , Toronto, ON , Canada ; Neuroscience and Mental Health Program, Hospital for Sick Children Research Institute , Toronto, ON , Canada ; Department of Medical Imaging, University of Toronto , Toronto, ON , Canada ; Department of Psychology, University of Toronto , Toronto, ON , Canada ; Department of Paediatrics, University of Toronto , Toronto, ON , Canada.

ABSTRACT
The frontal lobes are involved in many higher-order cognitive functions such as social cognition executive functions and language and speech. These functions are complex and follow a prolonged developmental course from childhood through to early adulthood. Magnetoencephalography (MEG) is ideal for the study of development of these functions, due to its combination of temporal and spatial resolution which allows the determination of age-related changes in both neural timing and location. There are several challenges for MEG developmental studies: to design tasks appropriate to capture the neurodevelopmental trajectory of these cognitive functions, and to develop appropriate analysis strategies to capture various aspects of neuromagnetic frontal lobe activity. Here, we review our MEG research on social and executive functions, and speech in typically developing children and in two clinical groups - children with autism spectrum disorder and children born very preterm. The studies include facial emotional processing, inhibition, visual short-term memory, speech production, and resting-state networks. We present data from event-related analyses as well as on oscillations and connectivity analyses and review their contributions to understanding frontal lobe cognitive development. We also discuss the challenges of testing young children in the MEG and the development of age-appropriate technologies and paradigms.

No MeSH data available.


Related in: MedlinePlus

Atypical neural oscillations in very preterm children. (A) Increased long-range phase synchrony during short-term memory retention in typically developing controls. (B) Altered long-range synchronization during memory retention in very preterm children, suggesting that alpha-band connectivity may be slowed toward the theta frequency range. (C) Slowing of spontaneous MEG oscillations in very preterm children (blue line represents typically developing controls; red line represents preterm children). (D) Regional analysis of oscillatory slowing in very preterm children indicates involvement of frontal lobes. For these analyses, bandpass filtering and the Hilbert transform were used to obtain phase and amplitude values for each frequency and sensor. Long-range phase synchronization was indexed using phase locking values [PLVs; see (Lachaux et al., 1999)].
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Figure 8: Atypical neural oscillations in very preterm children. (A) Increased long-range phase synchrony during short-term memory retention in typically developing controls. (B) Altered long-range synchronization during memory retention in very preterm children, suggesting that alpha-band connectivity may be slowed toward the theta frequency range. (C) Slowing of spontaneous MEG oscillations in very preterm children (blue line represents typically developing controls; red line represents preterm children). (D) Regional analysis of oscillatory slowing in very preterm children indicates involvement of frontal lobes. For these analyses, bandpass filtering and the Hilbert transform were used to obtain phase and amplitude values for each frequency and sensor. Long-range phase synchronization was indexed using phase locking values [PLVs; see (Lachaux et al., 1999)].

Mentions: Magnetoencephalography has also been shown to be of specific relevance for understanding atypical development of frontal lobe systems in children born preterm. Frye et al. (2010) demonstrated altered frontal lobe activation during language processing in preterm-born adolescents, which was interpreted as compensatory top–down control from prefrontal cortical regions. Visual short-term and working memory retention has been demonstrated to recruit increased phase coherence between frontal and posterior brain regions in multiple frequency ranges, with alpha-band oscillations playing a pivotal role in task-dependent coupling (Palva et al., 2005, 2010a,b). This pattern of task-dependent network coherence is also robust in school-age children (Doesburg et al., 2010a; Figure 8A). In contrast, school-age children born very preterm exhibit reduced inter-regional coherence and atypical regional activation during visual short-term memory retention (Cepeda et al., 2007; Doesburg et al., 2010b, 2011a). This was manifest as reduced task-dependent inter-regional synchronization in preterm children, which was correlated with cognitive outcome in this group (Doesburg et al., 2011a). Close inspection of the spectral signature of task-dependent connectivity suggested that alpha coherence might be slowed in preterm children, as inter-hemispheric phase synchronization was significantly reduced at alpha frequencies, but increased in the theta range (Figure 8B).


Neuromagnetic vistas into typical and atypical development of frontal lobe functions.

Taylor MJ, Doesburg SM, Pang EW - Front Hum Neurosci (2014)

Atypical neural oscillations in very preterm children. (A) Increased long-range phase synchrony during short-term memory retention in typically developing controls. (B) Altered long-range synchronization during memory retention in very preterm children, suggesting that alpha-band connectivity may be slowed toward the theta frequency range. (C) Slowing of spontaneous MEG oscillations in very preterm children (blue line represents typically developing controls; red line represents preterm children). (D) Regional analysis of oscillatory slowing in very preterm children indicates involvement of frontal lobes. For these analyses, bandpass filtering and the Hilbert transform were used to obtain phase and amplitude values for each frequency and sensor. Long-range phase synchronization was indexed using phase locking values [PLVs; see (Lachaux et al., 1999)].
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4061489&req=5

Figure 8: Atypical neural oscillations in very preterm children. (A) Increased long-range phase synchrony during short-term memory retention in typically developing controls. (B) Altered long-range synchronization during memory retention in very preterm children, suggesting that alpha-band connectivity may be slowed toward the theta frequency range. (C) Slowing of spontaneous MEG oscillations in very preterm children (blue line represents typically developing controls; red line represents preterm children). (D) Regional analysis of oscillatory slowing in very preterm children indicates involvement of frontal lobes. For these analyses, bandpass filtering and the Hilbert transform were used to obtain phase and amplitude values for each frequency and sensor. Long-range phase synchronization was indexed using phase locking values [PLVs; see (Lachaux et al., 1999)].
Mentions: Magnetoencephalography has also been shown to be of specific relevance for understanding atypical development of frontal lobe systems in children born preterm. Frye et al. (2010) demonstrated altered frontal lobe activation during language processing in preterm-born adolescents, which was interpreted as compensatory top–down control from prefrontal cortical regions. Visual short-term and working memory retention has been demonstrated to recruit increased phase coherence between frontal and posterior brain regions in multiple frequency ranges, with alpha-band oscillations playing a pivotal role in task-dependent coupling (Palva et al., 2005, 2010a,b). This pattern of task-dependent network coherence is also robust in school-age children (Doesburg et al., 2010a; Figure 8A). In contrast, school-age children born very preterm exhibit reduced inter-regional coherence and atypical regional activation during visual short-term memory retention (Cepeda et al., 2007; Doesburg et al., 2010b, 2011a). This was manifest as reduced task-dependent inter-regional synchronization in preterm children, which was correlated with cognitive outcome in this group (Doesburg et al., 2011a). Close inspection of the spectral signature of task-dependent connectivity suggested that alpha coherence might be slowed in preterm children, as inter-hemispheric phase synchronization was significantly reduced at alpha frequencies, but increased in the theta range (Figure 8B).

Bottom Line: There are several challenges for MEG developmental studies: to design tasks appropriate to capture the neurodevelopmental trajectory of these cognitive functions, and to develop appropriate analysis strategies to capture various aspects of neuromagnetic frontal lobe activity.The studies include facial emotional processing, inhibition, visual short-term memory, speech production, and resting-state networks.We also discuss the challenges of testing young children in the MEG and the development of age-appropriate technologies and paradigms.

View Article: PubMed Central - PubMed

Affiliation: Department of Diagnostic Imaging, Hospital for Sick Children , Toronto, ON , Canada ; Neuroscience and Mental Health Program, Hospital for Sick Children Research Institute , Toronto, ON , Canada ; Department of Medical Imaging, University of Toronto , Toronto, ON , Canada ; Department of Psychology, University of Toronto , Toronto, ON , Canada ; Department of Paediatrics, University of Toronto , Toronto, ON , Canada.

ABSTRACT
The frontal lobes are involved in many higher-order cognitive functions such as social cognition executive functions and language and speech. These functions are complex and follow a prolonged developmental course from childhood through to early adulthood. Magnetoencephalography (MEG) is ideal for the study of development of these functions, due to its combination of temporal and spatial resolution which allows the determination of age-related changes in both neural timing and location. There are several challenges for MEG developmental studies: to design tasks appropriate to capture the neurodevelopmental trajectory of these cognitive functions, and to develop appropriate analysis strategies to capture various aspects of neuromagnetic frontal lobe activity. Here, we review our MEG research on social and executive functions, and speech in typically developing children and in two clinical groups - children with autism spectrum disorder and children born very preterm. The studies include facial emotional processing, inhibition, visual short-term memory, speech production, and resting-state networks. We present data from event-related analyses as well as on oscillations and connectivity analyses and review their contributions to understanding frontal lobe cognitive development. We also discuss the challenges of testing young children in the MEG and the development of age-appropriate technologies and paradigms.

No MeSH data available.


Related in: MedlinePlus