Brain-Wide Electrical Surge Precedes Every Spoken Word, Study Finds

Jerusalem, 12 May, 2026 (TPS-IL) -- (PAP) – Nearly half of the cerebral cortex areas become active a fraction of a second before a word is recalled, Prof. Michał Kucewicz from the Gdańsk University of Technology told PAP. He added that to recall a specific concept, scattered memory fragments are combined.

Dr. Michał Kucewicz, a professor at Gdańsk University of Technology (GUT), head of the Brain and Mind Electrophysiology Laboratory at the BioTechMed Centre at GUT, and his team conducted research on memory processing in the brain. Scientists from the Medical University of Wrocław and St. Anne’s University Hospital in Brno, Czech Republic, also participated in the work. The results were published in Nature Communications.

To investigate what happens in a person’s brain before they utter a recalled word, the team used studies of people with drug-resistant epilepsy — about one-third of all epilepsy sufferers. Patients had electrodes implanted to pinpoint the source of seizures, allowing researchers to record brain activity during various activities.

Patients from the Czech Republic, the United States, and Poland were asked to memorize words displayed on a computer screen and then pronounce them from memory. “We used simple nouns that are translated similarly in different languages, for example, ‘house’ or ‘tree,'” explained Kucewicz.

To the researchers’ surprise, it turned out that the patients’ brains showed not only local activity in the part responsible for speech, but a global phenomenon encompassing all five lobes of the cerebral cortex. “Before a word is uttered, synchronization of brain activity occurs at high wave frequencies. Before a word even enters the mind or is uttered, almost half of the brain regions become active for several dozen milliseconds,” the researcher emphasized.

This is because scattered fragments of memory are combined to recall a specific concept. Even simple nouns, referring to everyday objects or well-known animals, are not just words but concepts in the mind. “For example, the word ‘fish’ can evoke many more associations than just a visual image. In many people, the gustatory cortex will be activated because they think of a fish dish. In anglers, the motor cortex will be activated because they remember how to cast a fishing rod. Fish is also a symbol of Christianity, so if someone thinks about it, the associative area of ​​the brain associated with symbol processing will be activated,” the scientist explained.

Such concepts engage multiple parts of the brain: sensory, memory, and higher-order cognitive. This allows the entire concept associated with the word to emerge in the mind. “We saw this synchronous activity when words appeared on the screen and patients tried to remember them by mentally imagining the concepts. The activity was even more intense when they recalled the words at any time without any external stimulus. This means the word appeared only in their minds, and the visual cortex recreated or projected what they associated with it,” Kucewicz said.

He noted that the researchers made another important discovery. “We were surprised that fast brain waves (High-Frequency Oscillations, HFOs) weren’t limited to those we’ve known for a long time, i.e., those with a frequency of around 100 Hz (approximately 100 cycles per second). While the patients were encoding and recalling memories, we found globally synchronized waves up to a frequency of 250-300 Hz,” the scientist said.

The study also showed that global brainwave synchronization occurred up to 300 milliseconds before the patients began to say a word. “We could therefore observe how the brain prepares to pronounce a word, how, under the influence of recalling concepts or memories, one neural network after another was activated in a cascade,” the researcher described to PAP.

He added that these discoveries are a milestone in the study of brain activity. “We now know in what frequencies, parts of the brain, and at what times to look for activity underlying concepts and engrams, or memory traces. We can now check, for example, when a concept appears consciously in a patient’s mind and when it remains subconscious, or see what activity looks like for more complex, abstract concepts, such as ‘love’ or ‘justice.’ We also want to track electrical discharges in the brain not only during a half-hour test in the hospital, but also when patients later think about these words or sleep,” Kucewicz said.