Understanding Visual Perception and Memory: The role of Constant Curvature and Synaptic Plasticity

Visual perception is an important neurological process that helps us make sense of the world around us. Constant curvature is an important concept to understand when it comes to our visual perception since it provides an explanation for how the brain interprets and distinguishes forms. To make sense of what we see, our visual system takes complicated things and makes them into simpler ones, and constant curvature segments serve as the building blocks for this. Our brain can rapidly put these different types of visual input, for example a shape, together to generate a whole one by looking at the curves that bend at a constant rate. This allows for processes such as object recognition and our memory. It would be difficult for us to interpret the environment around us if forms couldn't be reduced to segments of continuous curvature. 

      In class, we had a notable guest speaker, Nicholas Baker, who discussed the importance of constant curvature segments and how our mind recognizes shapes and objects from visual inputs. Using Gestalt principles, he explains how we don’t actually look at an object’s physical properties to distinguish them, nor do we need to look at a certain place that an object is, to recognize it. Instead, we look for spatial relations among the object’s segmented lines, to recognize and retain its shape. Researcher Baker showed an example of a pine tree, where we take the contour shape of the tree and compress it into the shape of a triangle. This can be seen in many different forms of visual input. He also mentions how we perceive stick figures as humans, although it is just a few segments of lines put together to form what is universally known as a human figure. My question derived from this concept, if we know how we perceive representations from researcher Baker’s work, how do we store that information so that we can remember universal things like the human figure shapes?  

In a complementary study called "Dopamine receptor activity participates in hippocampal synaptic plasticity associated with novel object recognition," researchers explore the biochemical processes that improve memory recall, especially the role of dopamine, a neurotransmitter for pleasure and reward, which is also used to promote synaptic plasticity. In the study, they find that the role of dopamine receptor activity when looking at a novel object increases significantly, allowing for better memory storage. As we repeatedly look at an object, our synaptic plasticity strengthens, thus illustrating those principles from constant curvature research. So, when we see a new shape, our visual system breaks down the parts into similar segments, and the more we view an object or shape, we can recognize it more easily. The study of the role of dopamine receptors can be used to build off the constant curvature segments ideas, and together these two findings play an essential role in how our brain works to put together images of shapes. The reason why we understand that the stick figure represents a human figure can be universally explained because we see the image so many times, it is engraved in our minds. Our synaptic plasticity strengthens each time we see it, like when we see bathroom signs, and illustrates the crucial role of human cognition and neural processes. 

References:  

Baker, Nicholas, et al. “Constant Curvature Segments as Building Blocks of Two-Dimensional Shape Representation.” PLoS Biology, vol. 3, no. 6, 2005, pp. 1135-1147, doi:10.1371/journal.pbio.0030204. 

Morris, R.G.M., et al. “Dopamine Receptor Activity Participates in Hippocampal Synaptic Plasticity Associated with Novel Object Recognition.” Current Biology, vol. 29, no. 2, 2019, pp. 291-298, doi:10.1016/j.cub.2018.11.064.