Extreme limbic and ventricular asymmetry with preserved cognition — Cross-validated results from FreeSurfer, CAT12, and volBrain

Context
Adult male, born preterm in 1974 (~1.5 kg, no incubator). Lifelong sensory hypersensitivity (cutaneous, emotional, interoceptive) and chronic fatigue with preserved cognitive and physical function.
MRI performed at 3 T (isotropic T1).
Processing independently conducted for research purposes using FreeSurfer 7.4, CAT12 v12, and volBrain v1.

Main structural findings (consistent across methods)

  • Lateral ventricles: Left = 5,585 mm³ | Right = 10,051 mm³ → ~80 % asymmetry.
  • Amygdala: Left = 575 mm³ | Right = 1,674 mm³ → ~191 % asymmetry.
  • Thalamus: Left = 14,141 mm³ | Right = 12,277 mm³.
  • Hippocampus: Left = 3,795 mm³ | Right = 4,175 mm³ → relatively preserved.
  • Global cortical volume: 257,528 mm³ (within normal range).
  • Cortical thickness mean: ≈ 1.68 mm bilaterally.
  • WM-hypointensities: 76,225 mm³ (moderate for age 51).
  • Intracranial volume (eTIV): 1,875,692 mm³ → BrainSeg/eTIV = 0.867.

Amygdala subnuclei (FreeSurfer v22 module segmentHA_T1.sh)

  • Lateral nucleus: Left = 535 mm³ | Right = 1,009 mm³ → +88.5 %
  • Basal nucleus: Left = 338 mm³ | Right = 475 mm³
  • Whole amygdala: Left = 1,374 mm³ | Right = 2,160 mm³ → +57 %

This subnuclear pattern indicates that the asymmetry is primarily driven by the right lateral nucleus hypertrophy, the amygdaloid component most related to sensory-emotional input and associative learning.

Disconnectome estimate
Lesion-based structural disconnectivity models suggest ≈ 80 % thalamo-cortical and fronto-limbic disconnection on the right hemisphere, coherent with the volumetric asymmetries above.

Functional context
Despite these findings:

  • Resting heart rate ≈ 46 bpm — athlete-level parasympathetic tone, verified by cardiological assessment.
  • Federated athlete (football, endurance sports).
  • University degree and stable professional activity.

The coexistence of major limbic and ventricular asymmetries with intact cognitive and physical performance suggests long-term compensatory reorganization rather than pathology.

Aim of posting

  • To ask whether similar extreme yet functional asymmetries have been documented in the literature or public datasets.
  • To inquire which tract-based or connectivity-based tools (e.g. RTP2, MRtrix, FSL) could best complement this morphometric evidence, given that DWI data are currently limited.
  • To discuss how such findings are interpreted in non-clinical research frameworks (plasticity, compensatory adaptation, neurodevelopmental resilience).

Notes
This post is not for medical diagnosis but for methodological discussion on individual-level morphometry.
Raw output files (aseg.stats, aparc.stats, CAT12 and volBrain reports) are available upon request for scientific verification.
All analyses were performed personally, without institutional support; I am neither a neuroscientist nor a computer scientist, so apologies for any technical inaccuracies.