Connection Between Smell, Taste, Perception, Memory, and Cognition

Smell and taste are intimately connected, more so than any other two senses (Bakalar, 2012). Even though the immediate sensory inputs are completely different, smell and taste inputs are processed together. Impediments to smell such as blocked sinuses can impact the ability to fully taste food. Chewing and eating also "releases volatile molecules that travel through the back of the mouth to receptors in the lining of the nasal passages," (Bakalar, 2012).

Therefore, eating enhances the total sensory experience by adding inputs to the olfactory pathway that would not be present simply by sniffing something. When cognitive processes in the brain are added to the equation, the interface between smell and taste becomes even more potent. Smells and tastes have emotional and cognitive components to them that are well proven in neuroscience research. Smell creates what Shepherd (2006) calls "images…in the olfactory pathway," (p. 316). These "images" are linked with memories, even those that occurred prenatally (Bakalar, 2012).

Heightened emotional states, including the sense of feeling threatened or slighted, can significantly alter one's perception of both smells and tastes (Skarlicki, et al., 2013). Therefore, foods taste their best when both smell and taste receptors are unimpeded, and when emotional states are either positive or neutral. Emotions, thoughts, memories, and sensory input are all linked in complex neural maps. To make meals taste better, both smells and tastes can be altered. In fact, sight also has a strong bearing on food perception as appetite can be stimulated visually.

However, the most direct means by which to make a meal taste better would be to enhance the flavors according to personal preferences. Enhancing the flavors would generally entail simultaneously enhancing aromas, but not necessarily. Some flavor enhancers, like MSG, are odorless but add a sense of flavor. Flavor is a combination of taste and smell, and not just input from the taste buds. Moreover, altering flavor alone would not make a difference if the eater had a stuffed-up nose.

"Without that interplay of taste and smell, you wouldn't be able to grasp complex flavors," and would only be able to detect the most simplistic ones like sweet, sour, salty, bitter, and spicy (Koerth-Baker, 2008). Ideally, all of these flavor sensations will be balanced in the meal to create a pleasurable experience. The alterations to the taste of food must also conform to personal likes and dislikes. Yet not all people share the same tastes or preferences in food.

As Shepherd (2006) points out, "neural mechanisms contribute to food preference and food cravings." What foods one had been exposed to as a child and the memories associated with those foods are going to have a strong bearing on taste preferences. Personal preferences may be changed to favor sweet, salty, spicy, and other core flavors. Enhancing the taste of the food might also serve a survival function, because the brain has evolved to detect off flavors and smells in food that signal poison or undesirable bacteria.

"The sense of taste is important in alerting an individual to dangerous foods (poisonous or spoiled), assisting in the identification of various foods, and contributing to the flavor of foods and thus enjoyment and quality of life," (Cullen & Leopold, 1999, p. 57). To create the most memorable meal of a lifetime, more than just the right taste combinations needs to be present. The connection between the chemical senses, emotional memories, and the brain is evident in special occasion meals.

The entire setting is critical, from the geospatial and temporal location to the connotations of the food, to the sights, sounds, and smells in the environment. The people present will also make a difference in how the meal will be processed, experienced, and remembered. There are deep connections between the chemical senses emotional memories, and the brain.

"The subjective experience of the emotional potency of odor-evoked memory is correlated with specific activation in the amygdala during recall and offers new insights into the affective organization of memory," (Herz, R.S., Eliassen, J., Beland, S. & Souza, T., 2003, p. 371). Because people who feel threatened incorrectly perceive their food to be "off," and may sense their food to be threatening too, it is essential to be surrounded by people one loves and trusts (Skarlicki, et al., 2013). Tastes change over time in part because people accumulate new memories and experiences.

There are also important cognitive processes involved in taste preferences. A person who becomes a vegetarian may lose all interest in meat, even though meat was associated with pleasant childhood memories. This is because the cognitive process associated with things like killing animals evokes negative emotions like revulsion, which would in turn cause one to be repulsed by those animal foods.

The reverse can also be true, in that a person who had once been a vegetarian might travel to a country that was inspiring and personally transformative on an emotional level. The positive emotions associated with being in that new culture might cause the person to create new social connections, leading to mealtimes in settings that generate.