It is commonly said that "elephants never forget". From the website Elephant Voices:

Based on the evidence available, elephants seem to remember for years other individuals and places and learned skills. In experimental trials involving a large set of visual symbols and acoustic tones or commands captive elephants show exceptional ability to learn and retain information over long periods. Accounts by practised observers indicate that elephants are able to remember the voices (and perhaps scents) o individual people for over 12 years

How to explain this phenomenon? Recently came across some interesting research out of Caltech that looked at elephant brains with MRI technology:

The elephant has an unusually large and convoluted hippocampus compared to primates and especially to cetaceans.( MRI image above comes from the John Allman Lab at the California Institute of Technology).

In humans and other mammals, the hippocampus is the brain structure largely responsible for memory formation.

Within 5-8 years, I suspect neuroimaging technology will be far enough advanced that a quick 5 minute human brain scan will be able to assess hippocampal anatomy & connectivity, and rate a person’s:

1. Natural ability to memorize various pieces of information (semantic, episodic, procedural, etc…)
2. Susceptibility to develop Alzheimer’s disease and other types of dementia- decades before actual memory impairment sets in

On a further note regarding elephant intelligence, a recent study [Reference below] reveals that elephants can recognize themselves in mirrors- a sign of self-awareness.

To date, only 3 other animals have shown themselves capable of this task:

• humans
• dolphins
• apes

Reference: Plotnik JM, de Waal FBM, Reiss D. Self-recognition in an Asian elephant. Proc Natl Acad Sci U S A. 2006 Nov 7;103(45):17053-7

Tags: elephant, hippocampus, MRI