It has been well documented that some people’s senses are heightened, meaning that they see many more hues of a color compared to others, while another person may have significantly increased hearing acuity. Heightened senses are commonly found in individuals with a sense that is lost or not developed in the brain, such as in blindness or deafness. It has been hypothesized that the brain region that normally is used for perception and integration of a specific sense, like the occipital lobe for vision, will be developed to increase another sense such as hearing. Finally, senses can be heightened for short periods of time under the influence of the autonomic nervous system, such as during the fight-or-flight response.
Highly Sensitive People
Having heightened senses does not equate to being highly sensitive, meaning that a subtle stimulus can be amplified by a person’s sensory system(s), making the stimulus almost unbearable. It is estimated that about 20 percent of the population is highly sensitive, with men and women having this sensitivity equally, and that it is innate and not learned. Persons who are highly sensitive may have emotional experiences or responses that are significantly intensified, which may affect their social life, job performance, and intimate relationships. In fact, a single negative comment or the clicking of a pen can be internalized so much that the person may become confrontational or withdrawn.
Highly sensitive individuals may have a heightened sense of smell or touch, where the smell of hand lotion on another person can be extremely irritating just as much as an itchy fabric on their skin. These people tend to have zero tolerance for such stimuli.
Synesthesia as a Type of Heightened Senses
Synesthesia, or “joined perception,” is a condition in which sensations from one sense are simultaneously perceived by one or more additional senses. The two main categories used to classify synesthesia are (1) perceptual—triggered by sensory stimuli such as sights and sounds, and (2) conceptual—involving abstract concepts such as time and calendars. Those who have this condition are called synesthetes and their experiences are involuntary, with the associations being unique to the individual. For instance, synesthetes can hear, smell, or taste in colors or shapes. Synesthesia is estimated to occur in anywhere from 1 in 20,000 people to 1 in 200. One of the most common forms of synesthesia involves seeing letters, digits, and words in unique colors and is called grapheme-color synesthesia, while one of the more rare forms of synesthesia involves words being experienced as strong tastes, a type called lexical-gustatory synesthesia.
Loss of One Sense Resulting in Another Heightened Sense
In 2004, Gougoux and colleagues studied whether people who were born blind or lost their eyesight had a better sense of hearing. They found that blind people develop superior abilities in auditory perception and are significantly better at orienting themselves toward sound than persons who are sighted. In fact, many blind persons are better at identifying voices and pitch change between sounds compared to controls (persons with vision). However, this depended on the age at which the person became blind. Gougoux et al. found that the younger the onset of blindness (that is, from birth to two years of age), the better the person’s hearing sense was developed. They hypothesized that this increase was due to the plasticity of the brain at early ages. Additionally, people who lost their eyesight at an early age might not have increased nonspatial hearing compared to persons born with blindness.
Jennifer L. Hellier
See also: Auditory-Tactile Synesthesia; Blindness; Grapheme-Color Synesthesia; Lexical-Gustatory Synesthesia; Mirror-Touch Synesthesia; Spatial Sequence Synesthesia; Supertaster; Synesthesia
Bartz, Andrea. (2011). Sense and sensibility. Psychology Today. Retrieved from https://www.psychologytoday.com/articles/201107/sense-and-sensitivity
Gougoux, Frédéric, Franco Lepore, Maryse Lassonde, Patrice Voss, Robert J. Zatorre, & Pascal Belin. (2004). Pitch discrimination in the early blind. Nature, 430, 309.
Sole-Smith, Virginia. (2015). This is what it’s like to have extraordinarily heightened senses. Prevention. Retrieved from http://www.prevention.com/health/heightened-senses