Neurodevelopmental Trajectories of the Human Cerebral Cortex
Understanding the organization of the cerebral cortex remains a central focus of neuroscience. Cortical maps have relied almost exclusively on the examination of postmortem tissue to construct structural, architectonic maps. These maps have invariably distinguished between areas with fewer discernable layers, which have a less complex overall pattern of lamination and lack an internal granular layer, and those with more complex laminar architecture. The former includes several agranular limbic areas, and the latter includes the homotypical and granular areas of association and sensory cortex. Here, we relate these traditional maps to developmental data from noninvasive neuroimaging. Changes in cortical thickness were determined in vivo from 764 neuroanatomic magnetic resonance images acquired longitudinally from 375 typically developing children and young adults. We find differing levels of complexity of cortical growth across the cerebrum, which align closely with established architectonic maps. Cortical regions with simple laminar architecture, including most limbic areas, predominantly show simpler growth trajectories. These areas have clearly identified homologues in all mammalian brains and thus likely evolved in early mammals. In contrast, polysensory and high-order association areas of cortex, the most complex areas in terms of their laminar architecture, also have the most complex developmental trajectories. Some of these areas are unique to, or dramatically expanded in primates, lending an evolutionary significance to the findings. Furthermore, by mapping a key characteristic of these development trajectories (the age of attaining peak cortical thickness) we document the dynamic, heterochronous maturation of the cerebral cortex through time lapse sequences ("movies").
Available from: Tiffany Ho
- "Indeed, developmental differences account for much of the variation in fMRI activation patterns between non-depressed adults and adolescents during emotion processing (Cho et al., 2012). Furthermore, cortical thickness of distinct brain regions develops differently depending on their organization and function (Huttenlocher and Dabholkar, 1997; Shaw et al., 2008). Specifically, changes in the composition of the insular cortex during adolescence correspond to improved emotional regulatory skills and refinement of functioning such as improved impulsecontrol (Sisk and Zehr, 2005; Steinberg et al., 2009). "
[Show abstract] [Hide abstract]
ABSTRACT: Background: Major depressive disorder (MDD) is a leading cause of disability worldwide and occurs commonly first during adolescence. The insular cortex (IC) plays an important role in integrating emotion processing with interoception and has been implicated recently in the pathophysiology of adult and adolescent MDD. However, no studies have yet specifically examined the IC in adolescent MDD during processing of faces in the sad- happy continuum. Thus, the aim of the present study is to investigate the IC during sad and happy face processing in adolescents with MDD compared to healthy controls (HCL).
Methods: Thirty-one adolescents (22 female) with MDD and 36 (23 female) HCL underwent a well- validated emotional processing fMRI paradigm that included sad and happy face stimuli.
Results: The MDD group showed significantly less differential activation of the anterior/middle insular cortex (AMIC) in response to sad versus happy faces compared to the HCL group. AMIC also showed greater functional connectivity with right fusiform gyrus, left middle frontal gyrus, and right amygdala/parahippocampal gyrus in the MDD compared to HCL group. Moreover, differential activation to sad and happy faces in AMIC correlated negatively with depression severity within the MDD group.
Limitations: Small age-range and cross-sectional nature precluded assessment of development of the AMIC in adolescent depression.
Conclusions: Given the role of the IC in integrating bodily stimuli with conscious cognitive and emotional processes, our findings of aberrant AMIC function in adolescent MDD provide a neuroscientific rationale for targeting the AMIC in the development of new treatment modalities.
Journal of Affective Disorders 01/2016; 178. DOI:10.1016/j.jad.2015.03.012 · 3.38 Impact Factor
Available from: sciencedirect.com
- "It is now known that significant development occurs in the brain's grey and white matter and that those brain regions which are latest to mature are those responsible for complex human behaviours, notably the prefrontal cortex and temporo-parietal regions (Giedd et al., 1999; Gogtay et al., 2004; Shaw et al., 2008; Sowell et al., 1999). Different brain regions have also been shown to mature at different rates and with differing trajectories; for example, Shaw et al. (2008) found that evolutionarily older parts of the brain, such as the limbic system, mature in a simpler linear trajectory than regions that evolved more recently, such as the neocortex. Neurotransmitter systems also continue to develop; for example the dopaminergic system undergoes substantial remodelling during adolescence (Steinberg, 2008). "
[Show abstract] [Hide abstract]
ABSTRACT: Neuroimaging studies have shown continued structural and functional development in neural circuitry underlying social and emotional behaviour during adolescence. This article explores adolescent neurocognitive development in two domains: sensitivity to social rejection and Theory of Mind (ToM). Adolescents often report hypersensitivity to social rejection. The studies presented here suggest that this is accompanied by reduced responses in brain regions involved in emotion regulation. Studies on social rejection in adolescents with autism spectrum conditions will also be discussed. ToM is another social cognitive domain which undergoes neurocognitive development between adolescence and adulthood. ToM refers to the ability to understand others’ thoughts and intentions. Neuroimaging data suggest that the ability to integrate emotional information into ToM decisions continues to develop between adolescence and adulthood. In sum, these studies demonstrate ongoing development of social and emotional cognition during adolescence at both behavioural and neural levels, providing a neurocognitive framework for understanding adolescent behaviour.
- "Heterochronicity in neurodevelopmental trajectories (Sowell, Thompson, Leonard, et al. 2004; Shaw et al. 2008; Giedd et al. 2014) is a likely contributor to change in cognitive strategy when confronted with a task or decision, proceeding from a bottom-up approach (Posner and Petersen 1990; Fjell et al. 2012), "
[Show abstract] [Hide abstract]
ABSTRACT: Brain structural development continues throughout adolescence, when experimentation with alcohol is often initiated. To parse contributions from biological and environmental factors on neurodevelopment, this study used baseline National Consortium on Alcohol and NeuroDevelopment in Adolescence (NCANDA) magnetic resonance imaging (MRI) data, acquired in 674 adolescents meeting no/low alcohol or drug use criteria and 134 adolescents exceeding criteria. Spatial integrity of images across the 5 recruitment sites was assured by morphological scaling using Alzheimer's disease neuroimaging initiative phantom-derived volume scalar metrics. Clinical MRI readings identified structural anomalies in 11.4%. Cortical volume and thickness were smaller and white matter volumes were larger in older than in younger adolescents. Effects of sex (male > female) and ethnicity (majority > minority) were significant for volume and surface but minimal for cortical thickness. Adjusting volume and area for supratentorial volume attenuated or removed sex and ethnicity effects. That cortical thickness showed age-related decline and was unrelated to supratentorial volume is consistent with the radial unit hypothesis, suggesting a universal neural development characteristic robust to sex and ethnicity. Comparison of NCANDA with PING data revealed similar but flatter, age-related declines in cortical volumes and thickness. Smaller, thinner frontal, and temporal cortices in the exceeds-criteria than no/low-drinking group suggested untoward effects of excessive alcohol consumption on brain structural development.
Cerebral Cortex 09/2015; DOI:10.1093/cercor/bhv205 · 8.67 Impact Factor
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.