Von Economo neuron

Von Economo neurons, also called spindle neurons, are a special kind of brain cell found in mammals. They have a unique shape, like a spindle, with one long branch that sends signals and one branch that receives signals. Most brain cells have many branches that receive signals, but these cells are different.

These special neurons are found in only a few places in the brains of humans and other great apes, such as in areas that help us understand important situations and feelings. They have also been found in some other animals, like whales, elephants, and even some monkeys and deer. This suggests that these neurons developed separately in different animals for important reasons we are still learning about.

Von Economo neurons were first discovered and described in 1925 by a scientist named Constantin von Economo. Their unique structure and limited presence in certain brain areas make them very interesting to scientists studying how our brains work.

Evolutionary function and significance

Von Economo neurons were once thought to be special because they were only found in very smart or social animals like humans, some whales, and elephants. But later studies showed that these neurons exist in many more animals, like monkeys, sheep, cows, and deer. This suggests they might have an important role in many types of mammals, though we still don’t fully understand why.

Interestingly, in some whales like the bowhead whale, which isn’t very social and isn’t the smartest whale, these neurons are found everywhere in the brain. This shows that these neurons might not just be linked to being very smart or social.

In the anterior cingulate cortex

In 1999, a scientist named John Allman and his team at the California Institute of Technology discovered special brain cells called von Economo neurons in the anterior cingulate cortex of humans and some close relatives, but not in other animals. These neurons were larger in humans and bonobos compared to chimpanzees, gorillas, and orangutans.

These neurons act like messengers, helping to send important signals from deep inside the brain to other areas. They seem to help manage emotions and guide decisions, especially when recognizing mistakes or thinking through tough choices. When people feel strong emotions, such as love or anger, this part of the brain becomes more active, helping us understand and respond to those feelings.

In the fronto-insular cortex

At a meeting in 2003, researchers shared their discovery of special brain cells called von Economo neurons in a part of the brain called the fronto-insular cortex. This area of the brain seems to have changed a lot in humans over the last about 100,000 years.

The fronto-insular cortex is closely linked to another brain area called the insula. The insula and fronto-insular cortex are part of the insular cortex, which helps us understand where we are in space, our own thoughts and feelings, and how we feel emotions. The right side of this area is also important for helping us understand directions and see things turning in three dimensions.

Concentrations

Von Economo neurons are special brain cells found in certain areas of the brain. In the anterior cingulate cortex, humans have the most of these neurons, followed by some great apes like chimpanzees, gorillas, and orangutans. They are also found in animals such as cetaceans and elephants.

In the fronto-insular cortex, humans again have the highest number of these neurons, with gorillas having fewer, and chimpanzees and bonobos having the fewest among the great apes studied. These neurons are also present in the dorsolateral prefrontal cortex of both humans and elephants, often appearing alone or in small groups.

Clinical significance

Von Economo neurons may not develop properly in some mental health conditions. These conditions often involve changes in how a person sees the world, thinks, talks, and interacts with others. Research suggests these neurons might be involved in schizophrenia and autism, but scientists are still learning more.

In frontotemporal dementia, many von Economo neurons are lost. Early research thought Alzheimer's disease might affect these neurons, but later studies showed this is not the case.