Decision-Making in Phototropism of Sunflowers

Plants survive and prosper in harsh and changing environments, thanks to their decision-making abilities which enable them to identify available options, and select the preferable one. Such a task requires taking into account different types of sensory information and weighting conflicting needs. Here we investigate the ability of plants to integrate multiple stimuli. We focus on the phototropic response of sunflower seedlings to two opposing light stimuli of different intensities, and present a mathematical model which captures the experimental results.

This experimental paradigm is analogous to Two-Alternatives Forced-Choice (TAFC) tasks, commonly used to study decision-making in behavioral science, where the choice is expressed via a motoric. These tasks provide a window on the underlying decision-making processes. The results we present here lay the foundation for the quantitative study of decision-making in plant phototropism, which, in future, will allow the assessment of characteristics such as the speed-accuracy tradeoff.