Remission of lifelong episodic dyscontrol after bilateral dorsolateral temporal lobe damage

ABSTRACT

A 45-year-old married woman with fits of episodic dyscontrol since an early age suffered a bilateral injury of the dorsolateral temporal lobe after which such episodes vanished for good. The remission of her lifelong proneness to aggression was so remarkable that her relatives and friends unanimously welcomed her “new personality”. The post-traumatic taming in this case was an unanticipated collateral effect of brain damage with a salutary change of personality. This change possibly resulted from the release, due to the bitemporal injury, of inclinations that had not hitherto been fully expressed in the patient’s mind and behavior due to the overriding influence of episodic dyscontrol on her ordinary conduct.

KEYWORDS:

• Temporal lobe
• episodic dyscontrol syndrome
• frontotemporoinsular system
• post-traumatic aggressiveness

Acknowledgements

The authors are indebted to Mr. Theo Marins (IDOR), Mr. Rodrigo Basílio (IDOR) and Mr. Ivanei Bramati (IDOR) for their invaluable assistance with the analysis and reconstruction of the MRIs. RO-S is indebted to Mr. Jorge Baçal (in memoriam) and Mr. José Ricardo Pinheiro (Library of the Oswaldo Cruz Instituto, Rio de Janeiro) for the bibliographical searches and to Professor Omar da Rosa Santos (Gaffrée e Guinle University Hospital) for institutional support.

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

1. The nomenclature of the ventral white matter fascicles connecting the occipital with the frontal and temporal lobes is rather confusing (Catani, Jones, Donato, & Ffytche, 2003). Notwithstanding the vagaries of terminology, two distinct pathways make up these connections. One of them is indirect and connects the occipital and inferior temporal lobe through a series of short U fibers that run in the external sagittal stratum. Classically known as the “inferior longitudinal fascicle”, it has more aptly been subsumed under the designation “occipitotemporal projection system” (Tusa & Ungerleider, 1985). The other system is direct and composed of fast conducting long association fibers that connect the ventromedial extrastriate occipital cortex with (a) the anterior lateral and medial temporal cortices, and (b) the orbitofrontal and frontopolar cortices. This system has long been known as the inferior fronto-occipital fascicle (Forkel et al., 2014). The projections of both fiber systems are reciprocal. The MRI method used in the present article was sensitive to the IFOF only.