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A Comprehensive Protocol for Manual Segmentation of the Medial Temporal Lobe Structures
Published on: July 2, 2014
Hemispheric asymmetry, modular variability and age-related changes in the human entorhinal cortex
G Simic1, S Bexheti, Z Kelovic
1Department of Neuroscience, Croatian Institute for Brain Research, Zagreb University Medical School, Salata 12, Zagreb 10000, Croatia. gsimic@hiim.hr
Neuroscience
|January 18, 2005
Summary
The human entorhinal cortex shows age-related neuron loss, with larger areas and more neurons in the left hemisphere. This brain region
Area of Science:
- Neuroscience
- Human Anatomy
- Aging Research
Background:
- The verrucae areae entorhinalis (VAE) are crucial brain structures in the parahippocampal gyri, characterized by islands of layer II neurons.
- These areas are implicated in memory processing and are among the first affected by neurofibrillary changes during aging.
Purpose of the Study:
- To investigate age-related changes in the verrucae areae entorhinalis (VAE) in the human brain.
- To analyze neuronal number, surface area, and hemispheric asymmetry within the entorhinal cortex.
Main Methods:
- Analysis of VAE in 60 neurologically normal subjects (23-85 years old) using a casting method.
- Stereological estimation of neuron numbers in entorhinal islands using the optical fractionator in 10 subjects.
Main Results:
- A significant leftward asymmetry in VAE number and surface area was observed.
- A significant negative correlation between VAE area and age was found, indicating neuron loss.
- No significant difference in total neuron number between hemispheres, but a significant negative correlation with age.
- Frequent observation of heterotopias (clusters of small neurons) in the rostral entorhinal cortex.
Conclusions:
- The study confirms age-related neuron loss in the entorhinal cortex.
- Leftward asymmetry in VAE suggests potential functional lateralization for language-related memory processing.
- Findings align with the left hippocampus's role in verbal episodic memory.
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