What are your research topics?
Our research group focuses on functional networks of the human brain involved in attention and related cognitive functions. In this research, we have applied especially functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) combined with measurements of perception and behavior. For example, we have clarified cognitively controlled (“top-down”) and stimulus-driven (“bottom-up”) brain processes involved in attention to simple sounds and visual objects, as well as to more natural stimuli, such as audio-visual speech or written text at the presence of distracting speech. With our research methods, we have also studied possible effects of excessive digital technology use, for instance, frequent multitasking or video gaming, on adolescents’ distractibility and attention skills during listening to speech and reading, and currently, also during arithmetic tasks. With our collaborators, we also attempt to reveal functional and structural brain anomalies underlying attention deficit hyperactivity disorder (ADHD) and developmental dyslexia.
Based on your research, what is (are) the most central, most urgent, or most exciting unresolved question(s) in your research field?
Brain imaging methods, such as fMRI and EEG, have their own advantages and limitations. Importantly, they allow non-invasive mapping of human brain function. However, while fMRI has a millimeter-scale spatial accuracy, its temporal resolution is of the order of several seconds, which is slow compared with the speed of sensory and cognitive processes. On the other hand, EEG has sufficient millisecond-scale temporal resolution, but a relatively poor spatial resolution. However, novel multivariate statistical methods allow us to perform combined analysis of fMRI and EEG data. This fMRI-EEG fusion gives us a spatially and temporally more comprehensive picture of the dynamics of functional brain networks involved in cognitive functions. At the same time, it must be kept in mind, that only one cubic millimeter of gray matter in the cerebral cortex contains tens of thousands of neurons. Therefore, our methods can only be used to image human brain functions at the level of large neuron populations. Fortunately, despite their limited spatial resolution, our methods have been able to elucidate roles of different brain regions and their interactions in different cognitive functions.
Much of the traditional cognitive brain research has applied relatively simple stimulus materials, such as sinusoidal tones and greyscale gratings, and simple tasks performed by participants, such as reaction time tasks. However, technological advances have allowed for an increase in the complexity of experimental conditions, which now use, for example, audiovisual video footage of social interaction or self-paced task performance in virtual reality environments. Given that the human brain has evolved in complex physical and social environments during the evolution of the human species, it is interesting to study to what extent brain activity measured in such more naturalistic experimental conditions differs from that measured simplified experimental conditions applied by numerous previous studies.
For a psychologist and cognitive neuroscientist, the big question is, does imaging the human brain help us to understand better the functions and dysfunctions of the human mind. For example, are brain imaging studies able to reveal neurocognitive processes of which we ourselves are unaware, but which nevertheless influence our cognition and behavior, or can brain imaging reveal brain anomalies underlying developmental disorders such as ADHD and dyslexia. We are still a long way from resolving the neural basis of the human mind, but the rapid development of brain imaging and data analysis methods augurs a bright future for cognitive neuroscience and its clinical applications.