Hamed Bahmani

Neural correlates of perceptual transitions during binocular flash suppression

Imaging studies have shown involvement of a distributed network of brain areas including primary visual cortex (V1) and frontoparietal cortical network in perceptual alternations during bistable and multistable phenomena. However, the role of parietal cortex in perceptual transitions has not yet been investigated at the level of single neurons. In addition, the role of area V1 in perceptual organization is still a subject of intense debate. In three independent but yet coherent projects, we explored the role of parietal visual areas in perceptual transitions during binocular flash suppression (BFS). We also tested the hypothesis that synchronized activity in V1 carries perceptual information. Furthermore, we compared the extent to which neurons in V1 modulate by perception under anesthetized conditions and compared with awake, passively fixating animals. Our work confirms that a distributed network of cortical regions is responsible for the resolution of perceptual rivalry during bistable conditions. This includes areas as early as primary visual cortex and higher processing stages such as lateral intraparietal area (LIP). However, the strength of these modulations may depend on the level of engagement of subjects in an active task. We demonstrated that modulation of neural activity in the firing rates during passive fixation is essentially comparable to the anesthetized condition in V1. In addition, we provided evidence that modulation of firing rate is not the only neural correlate of perception and showed that neural synchronization in V1 can reflect perceptual state even in the absence of significant firing rate modulations. Orchestration of coherent activity observed in V1 can be triggered by the fast feedback signals from higher visual areas like LIP.

Uploading data to the brain

What if you can upload a language package to your brain in a few seconds or teach a person how to play tennis by a single click? There exists a growing body of literature on how to read the brain or 'decode' neural information. However, writing to the brain or 'encoding' information in neuronal networks has been left sterile. In this project, experiments in rodents are proposed to upload a navigation map to a rat's brain, or transfer post-learning knowledge of a particular behavioral task from one animal to another by using multi-electrode extracellular recording and neuronal microstimulation in real-time. If successful, 'The Matrix' will no longer be a sci-fi movie.
The "Experiment!" funding initiative by the Volkswagen Foundation addresses researchers in science and engineering as well as in the life sciences including behavioral biology and experimental psychology, who want to put a potentially transformative research idea to the test. They are given the opportunity to demonstrate preliminary evidence for a concept's potential during an exploratory phase. In the fourth call of this initiative, 18 out of a total of 544 project proposals were approved, including the exciting project of Hamed Bahmani from the Max Planck Institute for Biological Cybernetics, Tübingen, for which 87,000 will be provided.

https://tuebingen.mpg.de/en/detail/uploading-data-to-the-brain/