Project Details
The origin of specialized processing regions for evolutionary novel stimulus categories in the human brain
Applicant
Dr. Mareike Grotheer
Subject Area
Human Cognitive and Systems Neuroscience
Term
from 2016 to 2018
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 298695428
The ultimate aim of this project is to elucidate how regions specialized in the processing of specific visual stimuli arose in the human brain. Most of these highly specialized areas have developed throughout the course of human evolution and it is hence very difficult to understand their origin. Therefore, in the current proposal, I will focus on those brain regions dedicated to processing letters and numbers. These stimuli gained importance for humans too recently for specialized processing regions to have arisen by evolutionary mechanisms. Rather, the regions processing these stimuli develop by learning during the lifetime of the individual. Understanding this process is crucial in order to understand how we can compensate for damage or loss (e.g. by stroke or injury) of these, or similarly specialized regions. The first step in this ultimate aim is to understand if these areas are entirely separate entities, or if there is rather some functional / spatial overlap between these two regions. After all, such an overlap could potentially indicate that one area can compensate for the loss of the other area. To answer this question, three different experiments will be conducted within the framework of the current proposal. For the first experiment, participants will be presented with Roman Numerals, stimuli which, depending on the task, can function as either letters or as numbers. I hypothesize that such context is sufficient to shift activations from the letter to the number region and vice versa. This, in turn, would suggest that these areas are not completely functionally segregated. Further, I will focus on participants who have extensive training / experience in tasks related to either of the above mentioned categories (for example mathematicians or linguists) in order to determine if expertise can affect the size and / or functional properties of these regions. This too would indicate that the areas are not completely distinct functional entities. Finally, I will present participants with morphs of numbers and letters in order to investigate whether there is an abrupt or rather a continuous spatial transition of selectivity from one region to the other. A continuous transition would give further support to the notion that these areas are not completely functionally segregated, which, in turn, would highlight a new avenue to compensate for a loss of brain function.
DFG Programme
Research Fellowships
International Connection
USA