Finding thoughts in speech: How the human brain processes thoughts during natural communication
News Jun 20, 2014
For the first time, neuroscientists were able to find out how different thoughts are reflected in neuronal activity during natural conversations. Johanna Derix, Olga Iljina and the interdisciplinary team of Dr. Tonio Ball from the Cluster of Excellence BrainLinks-BrainTools at the University of Freiburg and the Epilepsy Center of the University Medical Center Freiburg (Freiburg, Germany) report on the link between speech, thoughts and brain responses in a special issue of Frontiers in Human Neuroscience.
"Thoughts are difficult to investigate, as one cannot observe in a direct manner what the person is thinking about. Language, however, reflects the underlying mental processes, so we can perform linguistic analyses of the subjects' speech and use such information as a "bridge" between the neuronal processes and the subject's thoughts," explains neuroscientist Johanna Derix..
The novelty of the authors' approach is that the participants were not instructed to think and talk about a given topic in an experimental setting. Instead, the researchers analysed everyday conversations and the underlying brain activity, which was recorded directly from the cortical surface. This study was possible owing to the help of epilepsy patients in whom recordings of neural activity had to be obtained over several days for the purpose of pre-neurosurgical diagnostics.
For a start, borders between individual thoughts in continuous conversations had to be identified. Earlier psycholinguistic research indicates that a simple sentence is a suitable unit to contain a single thought, so the researchers opted for linguistic segmentation into simple sentences. The resulting "idea" units were classified into different categories. These included, for example, whether or not a sentence expressed memory- or self-related content. Then, the researchers analysed content-specific neural responses and observed clearly visible patterns of brain activity.
Thus, the neuroscientists from Freiburg have demonstrated the feasibility of their innovative approach to investigate, via speech, how the human brain processes thoughts during real-life conditions.
Note: Material may have been edited for length and content. For further information, please contact the cited source.
Johanna Derix, Olga Iljina, Johanna Weiske, Andreas Schulze-Bonhage, Ad Aertsen, Tonio Ball. From speech to thought: the neuronal basis of cognitive units in non-experimental, real-life communication investigated using ECoG. Frontiers in Human Neuroscience, Published June 13 2014. doi: 10.3389/fnhum.2014.00383
Synaptotagmin 7 Ensures Efficiency of Inhibitory Signal TransmissionNews
Researchers at IST Austria define function of an enigmatic synaptic protein, synaptotagmin 7.READ MORE
Molecules in Spit Could Help Diagnose ConcussionsNews
Diagnosing a concussion can sometimes be a guessing game, but clues taken from small molecules in saliva may be able to help diagnose and predict the duration of concussions in children, according to Penn State College of Medicine researchers.READ MORE
Elpis BioMed Closes Funding Round to Commercialise Novel Technology Platform for Generating Human Cell TypesNews
New Cambridge spin-out company commercialises disruptive technology that enables rapid generation of pure and consistent batches of human cell types. Geographically diversified, top-tier investor team includes key industry leaders to support early company development.READ MORE