What produces thought?

Thoughts are really just electro-chemical reactions - but the number and complexity of these reactions makes it difficult to fully understand thoughts .

The human brain has about 100 billion neurons (neurons), linked together by trillions of connections, called synapses (synapses) . On average, each connection transmits about one signal per second. Some specialized connections also send up to 1,000 signals per second. "And somehow . these connections produce thought," said Charles Jennings, director of neuroscience at the Mc Govern Institute for Brain Research at the Massachusetts Institute of Technology (MIT).

What is happening in the beginning is really complicated, so it is not easy to follow from the beginning to the end of a thought."It's a bit like the question of where the forest starts. Is it starting from the first leaf, or the first root?" , Jennings said.

More simply, "thinking" comes directly from external stimuli - like a feather touching your skin, or when you see these words on a computer screen, or you hear an electric bell phone. Each of these events stimulates a series of signals in the brain.

For example, when you read these words, photons combined with letters hit your retina, and their energy stimulates an electronic signal in light detection cells. The transmission of this electronic signal is like a wave of advancing long wires called nerve axons.

Nerve axons are part of the connections between neurons. When the signal reaches the end of a nerve axon, it releases chemical neurotransmitters into the synapse, a chemical connection between the nerve fiber end and the target nerve cells. A target neuron reacts to its own electronic signal, and in turn this electronic signal spreads to other nerve cells.

Within just a few hundred milliseconds (one thousandth of a second), the signal has spread to billions of nerve cells in some areas of the brain and thus, you receive these words. All this process takes place in a brief period of time, even before you even have a breath.

However, the later you convert these perceptions into symbols, languages ​​and meanings is a completely different story - it also represents the complexity of neuroscience. Trying to visualize how trillions of connections and billions of continuous communication in the brain form a thought is like trying to look at leaves, roots, snakes , birds, deer, everything - everything in the forest - in the same moment.

However, with new brain imaging tools, researchers have made great strides in this work. A better way of understanding where and how different types of thoughts arise in the brain - such as facial recognition, emotion or language - can help researchers develop ways. treatment for disorders like autism.

But have scientists reached that goal?"It is a great goal , " said Evelina Fedorenko, a McGovern scientist. Working with Professor of Recognition Science and Brain Nancy Kanwisher, Fedorenko is working on developing better tools to dissect the logs of thought . Their current work has revealed a clearer picture of how the brain processes language - this is one of the activities that define our human nature.