Summary: A new study provides insights into the evolutionary origins of cognitive flexibility, an essential skill for adaptation and survival.
Participants were studied using functional magnetic resonance imaging (fMRI) while learning a sensorimotor task, the findings of which showed the importance of sensory brain regions in decision-making. The researchers also discovered surprising similarities between the brain activity of humans and mice during this task.
These results suggest that the interplay between the frontal brain and sensory brain regions for decision-making formed early in evolutionary development.
Cognitive flexibility, which allows quick adaptation to changing conditions, is crucial for survival and is based on the functions of the orbitofrontal cortex located in the frontal brain.
Sensory brain regions are critical in decision-making processes as discovered in the study, suggesting the need for further investigation in this area.
The similarity in cognitive processes between mice and humans suggests that these decision-making mechanisms likely developed early in evolutionary history.
Get up. Go to the kitchen. Prepare some cereal – but a look into the fridge shows: the milk bottle is empty. What now? Skip breakfast? Ask the neighbour for milk? Eat jam sandwiches? Every day, people are confronted with situations that were actually planned quite differently. Flexibility is what helps.
The origin of this skill in the brain is called cognitive flexibility.
A neuroscientific research team at the Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil, University Hospital of Ruhr University Bochum, Germany, and the Biosciences Institute at Newcastle University has now succeeded in getting a little closer to the evolutionary origin of cognitive flexibility.
The researchers published their findings in the journal Nature Communications, online since 9. June 2023.
Key factor in many neuropsychiatric diseases
Cognitive flexibility is essential for the survival of all species on Earth. It is particularly based on functions of the so-called orbitofrontal cortex located in the frontal brain.
“The loss of cognitive flexibility in everyday life is a key factor in many neuropsychiatric diseases,” Professor Burkhard Pleger and first author Dr. Bin Wang from the Berufsgenossenschaftliches Universitätsklinikum Bergmannsheil describe their motivation for the study.
“Understanding the underlying network mechanisms is therefore essential for the development of new therapeutic methods.”
Using functional magnetic resonance imaging (fMRI), the Bochum team and their cooperation partner Dr. Abhishek Banerjee from the Biosciences Institute at Newcastle University examined the brain functions of 40 participants while they were learning a sensorimotor task.
While lying in the MRI, the volunteers had to learn to recognise the meaning of different touch signals – similar to those used in Braille – on the tip of the right index finger. One touch signal told the participants to press a button with their free hand, while another signal instructed them not to do so and to remain still.
The connection between the two different touch signals and pressing the button or not pressing the button had to be learned from trial to trial. The challenge: after a certain time, the touch signals changed their meaning.
What had previously meant “pressing the button” now meant “holding still” – an ideal experimental set-up to investigate the volunteers’ cognitive flexibility. The fMRI provided images of the corresponding brain activity.
Similarities between humans and mice
“Similar studies had already been done with mice in the past,” says Pleger.
“The learning task we chose now allowed us to observe the brains of mice and humans under comparable cognitive demands.”
A surprising finding is the comparability between the Bochum results in humans and the previously published data from mice, Wang points out.
The similarity shows that cognitive functions that are important for survival, such as the flexibility to adapt quickly to suddenly changing conditions, are following comparable rules in different species.
In addition, the Bochum scientists were able to determine a close involvement of sensory brain regions in the processing of the decisions made during tactile learning. Wang emphasises: “Besides the frontal brain, sensory regions are essential for decision-making in the brain.”
“Similar mechanisms had also previously been observed in mice,” adds Pleger.
“This now suggests that the interplay between the frontal brain and sensory brain regions for decision-making was formed early in the evolutionary development of the brain.”
About this neuroscience research news
Author: Meike Driessen Source: RUB Contact: Meike Driessen – RUB Image: The image is credited to Neuroscience News
Human orbitofrontal cortex signals decision outcomes to sensory cortex during flexible tactile learning
The ability to respond flexibly to an ever-changing environment relies on the orbitofrontal cortex (OFC).
However, how the OFC associates sensory information with predicted outcomes to enable flexible sensory learning in humans remains elusive.
Here, we combine a probabilistic tactile reversal learning task with functional magnetic resonance imaging (fMRI) to investigate how lateral OFC (lOFC) interacts with the primary somatosensory cortex (S1) to guide flexible tactile learning in humans.
fMRI results reveal that lOFC and S1 exhibit distinct task-dependent engagement: while the lOFC responds transiently to unexpected outcomes immediately following reversals, S1 is persistently engaged during re-learning.
Unlike the contralateral stimulus-selective S1, activity in ipsilateral S1 mirrors the outcomes of behavior during re-learning, closely related to top-down signals from lOFC.
These findings suggest that lOFC contributes to teaching signals to dynamically update representations in sensory areas, which implement computations critical for adaptive behavior.