A team of researchers said for the first time they have returned a mammal's brain to an operational state after it was cryogenically frozen.

"​Every neuron and synapse looks beautifully preserved across the entire brain," Dr. Kenneth Hayworth, president of the Brain Preservation Foundation, said in a press release. "Simply amazing given that I held in my hand this very same brain when it was vitrified glassy solid... This is not your father's cryonics."

The process is called Aldehyde-stabilized cryopreservation and it entailed filling the brain, which belonged to a rabbit, with chemicals that protected it from the minus-211 degree Fahrenheit state it was kept in.

"The brain was able to be sliced and viewed in an electron microscope which suggested that all the connections had been preserved," Michael Cerullo, a psychiatrist at the BPF, told Newsweek.

Published in the journal Cryogenics, the new study detailed how the technique can advance how scientists study the brain.

"This is a technique designed for use by neuroanatomists to better study brain structure," study co-author Gregory Fahy, vice president and chief scientific officer at 21st Century Medicine, told The Huffington Post. "This is the first method that perfectly preserves the structure of an entire brain such that, unlike conventional methods, every single part of the brain can be studied in detail to build up a picture of the entire brain."