Memory, Color, and the Visual Cortex of the Brain
A community consciousness and brain health essay.
When we remember an event, we remember certain types of sensations — the color of the car that hit us, the shape of the tree that fell in the wind storm, the feeling of salt water on our feet as we walked on the sandy beach, or the color of the shirt we were wearing when we got engaged.
Medical research indicates that our perception of sensations in the moment as well as our memory of events can improve with practice.
Here are two exercises that focus on color and shape recognition and improving memory:
Exercise 1. Pick up a small item. Look at it. Observe the color, shape, and texture. Listen for the sound it makes when you tap on it. Notice the patterns. Does it have a taste or smell? What does it feel like? Describe in words aloud all the sensations you feel — the color as the light bounces on your eyes, the sound waves beating on your ear drums, the texture as the skin on your fingertips touch the object. A minute of paying specific attention can improve your sensations, mood, and relaxation.
Exercise 2. Look outside at the tree. Notice the shape. Peer deeply into the center of one particular tree. Do you see any animals? Does the tree have needles or leaves? Does the color differ at the bottom of the tree where the tree meets the earth or as the tip top branches reach for the sky? What do your observations tell you about the type of tree or about the season of the year or about the function of that particular tree. Now choose another tree. Notice how each tree is unique and yet can be categorized by the shape of the leaves, the curve of the branches, the color of the bark. See the patterns.
The second exercise is based on research that indicates that we learn more about shape recognition from looking at things like trees that are uniquely shaped and yet have a pattern that can be learned. We can learn to recognize hundreds of different kinds of trees, cars, dogs, or airplanes. Each item in the category is similar and different. We can focus on the similarities and understand that we are looking at a tree. We can focus on the differences and understand that we are looking at a mountain ash or a Japanese maple. They are both trees with leaves but have many other differences from each other, and similarities with other mountain ashes or Japanese maples.
Here is what the research says: “There is substantial evidence that object representations in adults are dynamically updated by learning. We had two training conditions: “categorized objects” were categorized at a subordinate level based on fine shape differences (Which type of fish is this?), whereas “control objects” were seen equally often in a task context requiring no subordinate categorization (Is this a vase or not?). After training, the object-selective cortex [brain] was more selective for differences among categorized objects than for differences among control objects. This result indicates that the task context during training modulates the extent to which object selectivity is enhanced as a result of training.” (Gillebert, C. R., H. P. Op de Beeck, et al. (2009). “Subordinate categorization enhances the neural selectivity in human object-selective cortex for fine shape differences.” Journal of Cognitive Neuroscience 21(6): 1054–1064.
This research suggests a further exercise:
Exercise 3. Pick a category of things you are interested in, cats, cars, birds, boats, rock formations or riffles. Check out a book from the library, buy a book on Amazon, or look up images online. Learn something new. Study items in the category until you can recognize 25 to 100 different items in that category.
A recent study in Neuroimage noted, “Visual object perception is an important function in primates which can be fine-tuned [improved] by experience, even in adults. In sum, training to categorize or individuate objects strengthened pre-existing representations in human object-selective cortex [brain], providing a first indication that the neuroanatomical distribution of learning effects depends upon the pre-learning mapping of visual object properties.” (Brants, M., J. Bulthe, et al. (2016). “How learning might strengthen existing visual object representations in human object-selective cortex.” Neuroimage 127: 74–85
Another study highlights different areas of the brain which handle and distribute incoming sensory information. Visual information is typically interpreted and stored in the occipital lobe or the visual cortex.
A recent study in Neuroimage looked at how and from where we retrieve visual (color and shape) information and found that colors and shapes activate not only the occipital lobe but also the temporal lobe which typically processes sound information and other sensory information.
“During the study, subjects were asked to encode colored (red or green) and achromatic [without color] random shapes. At subsequent testing, subjects were presented with only achromatic shapes, which had been presented with or without colors during encoding, and were engaged in retrieval tasks of shapes and colors.”
Researchers found overlapping activity “in the medial temporal lobe and occipital lobe (the lingual and inferior occipital gyri) in the right hemisphere during the encoding and retrieval of meaningless shapes with color information compared with those without color information.” (Ueno, A., N. Abe, et al. (2007). “Reactivation of medial temporal lobe and occipital lobe during the retrieval of color information: A positron emission tomography study.” Neuroimage 34(3): 1292–1298. NeuroImage.
This research indicates that if an area of the brain is damaged specific exercises can improve its function. When two or more areas of the brain function in a similar way such as the temporal lobe and occipital lobe encoding the memories of shape and color, function can be enhanced by exercises that ask both the injured area to work at a task and strengthening the uninjured areas with exercises.
Exercise 4. Call to mind an experience or an event that happened to you yesterday. What colors, shapes, tastes, or smells can you remember? Then think of something from several years ago. What sensations of the experience do you remember?
Originally published at ABI Recovery Magazine on January 15, 2018.
