When the brain is under pressure, certain neural signals begin to oscillate synchronously – much like a well-rehearsed orchestra. A new study conducted at Johannes Gutenberg University Mainz (JGU) shows for the first time how flexibly this neural synchrony adapts to different situations and that this dynamic coordination is closely linked to cognitive abilities.

“Specific signals in the middle frontal region of the brain are better synchronized in people with higher cognitive abilities – especially during demanding phases of thinking,” explains Professor Anna-Lena Schubert from the Institute of Psychology at JGU, first author of the study, which was recently published in the Journal of Experimental Psychology: General. The researchers focused on the middle frontal region of the brain and the measurable coordination of so-called theta waves. These brain waves oscillate between four and eight hertz and are among the slower neural frequencies. “They tend to occur when the brain is particularly challenged, for example when we are concentrating or when we have to consciously control our behavior,” says Schubert, who heads the Laboratory for Analysis and Modeling of Complex Data at JGU.

People With Stronger Theta Connectivity in the Middle Frontal Region are Often Better Able to Concentrate Despite Distractions

The 148 participants in the study, aged between 18 and 60, first completed tests to assess their memory and intelligence before their brain activity was recorded using electroencephalography (EEG). This procedure measures tiny electrical signals in the brain using electrodes attached to the scalp and is a proven technique for gaining precise insights into cognitive processes. During the EEG recording, the participants completed three mentally demanding tasks designed to assess cognitive control.

The researchers were interested in the participants’ ability to switch flexibly between changing rules, which is an essential aspect of intelligent information processing. For example, participants had to press a button to decide whether a number was even or odd and, shortly thereafter, whether it was greater than or less than five. Each rule change required a quick adjustment of mental strategies—a process that allowed the researchers to closely observe the coordination of networks in the brain in real time.

The result: individuals with higher cognitive abilities showed particularly strong synchronization of theta waves at crucial moments, especially during decision-making. Their brains were better able to maintain focused thoughts when it mattered. “People with stronger theta connectivity in the middle frontal region are often better at concentrating and blocking out distractions, whether it’s a cell phone vibrating while they’re working or trying to read a book in a busy train station,” Schubert explained.

Study Provides Important Insights Into How Intelligence Works at the Neural Level

Professor Anna-Lena Schubert was particularly surprised by how closely this coordination of brain rhythms is linked to cognitive abilities. “We didn’t expect the connection to be so clear,” she said. The decisive factor was not continuous synchronization, but the brain’s ability to adjust its timing flexibly and contextually – like an orchestra following an experienced conductor. The midfrontal region often sets the tone for this coordination, but it works together with other areas of the brain. This midfrontal theta connectivity appears to be particularly relevant when decisions are made, but not during mental preparation for new task rules.

Previous EEG studies on cognitive performance mostly examined activity in isolated brain regions. In contrast, this study took a network-based approach and examined how different areas interact during multiple tasks to identify stable, overarching patterns. The results show that individual differences in cognitive performance are related to the dynamic network behavior of the brain. According to the researchers, potential applications such as brain-based training tools or diagnostics are still a long way off. However, the study would provide important foundations for understanding how intelligence works at the neural level. A follow-up study, for which participants aged 40 and older from the Rhine-Main region are currently being recruited, will investigate which biological and cognitive factors additionally support this type of efficient brain coordination and what role other cognitive abilities such as processing speed and working memory play.