Related Experiment Video
Updated: Oct 4, 2026

Hippocampal Insulin Microinjection and In vivo Microdialysis During Spatial Memory Testing
Published on: January 11, 2013
Reversible amnesia in a Type 1 diabetic patient and bilateral hippocampal lesions on magnetic resonance imaging (MRI)
X Holemans1, M Dupuis, N Misson
1Service de Médecine Interne, Centre Hospitalier Notre-Dame et Reine Fabiola, Charleroi, Belgium. xavier.holemans@chndrf.be
Aims:
Intensive insulin therapy of Type 1 diabetes limits its chronic complications, but is associated with an increased risk of severe hypoglycaemia and its neuroglycopenic consequences.
Methods:
Case report.
Results:
A 24-year-old male with 15 years' history of Type 1 diabetes, who was missing for 48 h, was found at home in ketoacidosis coma. Intensive care permitted a rapid improvement revealing an unexpected severe anterograde amnesia, confirmed by neuropsychological testing. MRI performed 4 days after admission showed abnormal bilateral hyperintensity signals on T2-weighted images in the hippocampus. Three months later, the patient had nearly completely recovered and resumed work. MR images and neuropsychological testing returned to normal.
Conclusions:
The most likely course of events favours an initial prolonged hypoglycaemic coma following insulin overdose. The hippocampal injury may be a result of hypoglycaemia. Neuropsychological testing and MRI abnormalities were completely reversible. This case underlines the potential risks of intensive insulin therapy.
Related Concept Videos
Amnesia
The severity and duration of memory loss vary depending on the type and underlying cause. Amnesia is classified into two main types: retrograde and anterograde.
Retrograde amnesia is marked by the loss of memories formed before the onset of the condition. Patients may recall distant past events but often forget those occurring shortly before the incident.
Anterograde...
Role of Hippocampus in Memory
Higher Mental Functions of Brain: Learning and Memory

