Brain Stimulation and Decision-making

In recent years, countless studies have employed functional magnetic resonance imaging (fMRI) and other imaging modalities to both discover and track activity in brain regions involved in performance or behavior in a wide range of tasks. Running in parallel, research involving neuromodulation has afforded researchers the opportunity to test the impact of direct stimulation on areas hypothesized to be involved in certain processes or behaviors. Among such technologies are transcranial magnetic stimulation (TMS) and temporal interference (TI). TMS and TI can be performed during any sort of cognitive or behavioral task to estimate the effect of the stimulated brain area; as such, TMS and TI have an exciting array of potential applications in research. One area, for example, is cost-benefit decision-making. Because of the potential biases associated with self-report measures-including simple recall errors, misinterpretations of the item, and social-conformity pressures-a number of psychological laboratories have advocated for the use of decision-making tasks as an alternative means of assessing motivation and reward-related symptoms. Such tasks ask individuals to choose how much they are willing to work, wait, or risk to win various rewards. These measures have been used in a variety of behavioral and neuroimaging studies and in different clinical populations. This study will use TMS or TI in combination with a series of behavioral tasks to probe the relationship between areas known or hypothesized to be involved in cognition and/or cost-benefit decision-making, and performance on these tasks. This study aims to understand the effect of TMS or TI stimulation of certain brain areas on performance in a series of cognition- and decision-based behavioral tasks. To do so, the researchers will stimulate areas of the cortex hypothesized to be selectively engaged with cognition of a given category, or cost-benefit decision-making (depending on the behavioral tasks used). This study will examine healthy controls and depressed patients to investigate these effects. Such an aim will not only provide a deeper understanding of decision-making for basic research but will also hopefully inform understanding when decision-making is altered, as in psychiatric populations.