One of the most familiar characteristics of the human brain are its grooves (sulci) and folds (gyri). But not everyone’s brain is the same when it comes to these structures.

Roughly 1 out of every 85,470 children are born with a rare brain condition known as lissencephaly, which is characterized by a lack of sulci and gyri.

The condition is a result of abnormal neuron migration during the early weeks of embryo development, and most people born with it pass away before the age of 10. Symptoms include difficulty feeding/swallowing, malformation of fingers, toes and hands, muscle spasms, seizures and intellectual impairment.

Adam Voorhes is an independent commercial and editorial photographer based in Austin, Texas. His well-known clients include Texas Monthly, ESPN and Esquire, among many others.

For an upcoming book, Voorhes photographed a collection of approximately 100 brains that were gathering dust in a storage closet in the back of a University of Texas animal lab.

The brains, which date back to the 1950s, belonged to deceased patients from the Austin State Mental Hospital. They had been locked away and forgotten for more than 20 years before being re-discovered by Voorhes (he was informed of their existence by psychology lab professor Tim Schallert).

Among the collection was this extraordinarily smooth specimen:

Even for those suffering from lissencephaly, this level of smoothness is extremely rare. In an interview with the New Scientist, David Dexter, scientific director at Parkinson’s UK Brain Bank, said that he had never seen an adult brain quite like this one:

“We do get the odd individual where certain sulci are missing but nothing to the extent of this brain.”

Voorhes pored through a century worth of paperwork and documents about the brains, trying to find out more about the patient behind this rare specimen. Unfortunately, his research was unable to uncover any detailed information about the individual, though he did discover that the brain collection had sparked a number of ownership battles over the years.

Researchers at the University of Texas are currently using high-resolution MRI machines to document the brains in more detail. When this process is complete, the brains will be put on display at UT’s Imaging Research Center.

Check out some more photos of the brain collection below:

The images above are from Voorhes’s new book Malformed: Forgotten Brains of the Texas State Mental Hospital.

Read the original story from IFL Science.