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features the brain reveal that they are very strongly connected with the emotional centers of the brain, namely with the amygdala.

Attention, Expectation, and Distinction

Local field potentials in gustatory cortex in response to a gustatory stimulus and spectogram of response frequencies.

simple scenario: when you consume candy you experience a taste that is “over the top” and very satisfying. Since you like the way it tastes, you also get used to the visual appearance of what you are eating. This accomplishes two things: you get used to an “over the top” taste, such as excessive sweetness, and an appearance that is completely unnatural. The solution to the problem of unhealthy eating is to get people conditioned to healthy foods, which have less excessive taste and a natural appearance. Encouraging healthy choices early on in life will help an individual’s development into a healthy adult. Since the OFCBLA-INS loop undergoes maturation, we can program it to prefer natural and healthy choices as early as the preadolescent stage.

Learning to dislike An issue encountered by many college students over the age of twenty one is alcohol intoxication, which may lead to extreme sickness through alcohol poisoning. Experiencing this can, in turn, lead to the development of an aversion to alcoholic beverages. This is an example of associative learning, termed Conditioned Taste Aversion, which has a profound meaning for our survival. Dr. Fontanini presents an example of this: If you are put into the wild and taste something novel that makes you sick, your body will signal to your brain that whatever you just tasted is potentially poisonous. This signal will create an aversion for the food that caused the illness. This is a way to ensure you do not give the poison a second chance to kill you by consuming it again. The same process of aversion has been observed in laboratory animal studies [4].

How do the factors of attention level and expectation modulate processing of taste processing and gustatory cortical activity? Levels of attention tremendously change the way tastes are perceived. If a person pays more attention to what he tastes, he or she can then better discriminate the basic tastes - sweet, sour, salty, bitter, and umami. For instance, in experiments conducted with mice, the animals make the most efficient distinction on whether the odor is dangerous or not, accurately discerning whether something is a predator or prey. If, however, the mouse is not paying attention, its main concern is whether the odor is pleasant or not. Once it makes this distinction, the brain becomes activated, causing the animal to become attentive and discriminate whether the smell represents an item that is both good and physiologically necessary, such as a salty food. It is the ability to discriminate between different aspects of information that changes depending on one’s state of attention [2].

A Big Challenge for Behavioral Neuroscientists How do we convert expectations to quantitative data? How do we objectively measure neurological processing? The answer to these questions lies in the careful analysis of behavior. One can examine if an animal likes or dislikes something based on a few different measures, including how much it consumes of the substance (motivation) and which substance it prefers. This can be done by observing oro-facial reactions, which are “funny faces” mice make when they are given something to taste. When they dislike what they tasted, mice engage in gaping behavior, which involves attempting to remove the substance from their mouth with their paws. If they like the substance, they lick their

Remembrance of Things Past The renowned, French author Marcel Proust wrote seven volumes of remembrance and memories that all began with the smell of a Madeleine known as “Remembrance of Things Past” [5]. Both odor and taste are very powerful in evoking emotions through the OFC-BLA-INA circuit in the brain. Taste, even in its simplest form, is a very emotional sensory system. Studies on the interaction between the olfactory and gustatory areas of

lips.Local field potentials and action potentials from c a nmultiple neurons in a rat brain. into

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