Recently discovered photographs of Albert Einstein's brain made after his death show it was unlike those of most people, a U.S. researcher says.

After Einstein died in 1955, his brain was removed and photographed but many of the photos were thought to be lost for more than 55 years.

Fourteen were recently uncovered by the National Museum of Health and Medicine in Silver Spring, Md., as part of a donation from the estate of Thomas Harvey, the pathologist who took the original photos, USA Today reported.

A study of the photographs was led by Florida State University evolutionary anthropologist Dean Falk.

"Einstein's brain has an extraordinary prefrontal cortex, which may have contributed to ... some of his remarkable cognitive abilities," Falk said.

The study is being published in the journal Brain.

"Although the overall size and asymmetrical shape of Einstein's brain were normal, the prefrontal, somatosensory, primary motor, parietal, temporal and occipital cortices were extraordinary," Falk said.

After the photos were taken, the brain was dissected into 240 separate pieces, most of which remain at the University Medical Center in Princeton, N.J.. The locations of some of the brain segments are unknown.