Preferring a Taste and Recognizing It May Involve Separate Brain Areas, Study Shows

Jul 01, 2005

Are you disgusted when you hear about Elvis Presley's fried peanut butter 'n 'nanner sandwiches? A new study shows that it could all be in your head. In fact, our taste preferences may have little to do with whether we can even recognize the substance we're eating or drinking.

In the current issue of Nature Neuroscience, California Institute of Technology neuroscientist Ralph Adolphs and his colleagues at the University of Iowa report on their examinations of a patient whose sense of taste has been severely compromised. The patient suffered from a herpes brain infection years ago that left him with brain damage. Today, the patient is unable to name even familiar foods by taste or by smell, and shows remarkably little preference in his choice of food and drink.

According to Adolphs, who is a professor of psychology and neuroscience at Caltech, the subject is a 72-year-old man, known as "B," whose brain infection destroyed his amygdala, hippocampus, the nearby temporal cortices, and the insula, and damaged several other brain structures. As a result, the patient today has a memory span of about 40 seconds, somewhat similar to that of the character in the film Memento.

As a result of his extensive brain damage, B is unable to recognize familiar people and many objects, although his vision and his use of language are unaffected. In terms of taste, he fails to recognize any familiar food items, and could probably outdo even Elvis by wading into a banana and mayonnaise sandwich with gusto.

"Our likes and dislikes in taste stem from both innate and cultural causes," Adolphs explains. "You may like sushi or bitter melon or certain smelly cheeses, whereas other people turn away from these foods in distaste."

The research shows that it may be possible to like or dislike certain foods without being able to recognize them at all, and that different regions of the brain are responsible for these two processes.

To test this hypothesis, the researchers set up an experiment in which B, several other subjects with brain damage, and several normal subjects were all offered salty and sweet drinks. All the subjects drank the sweet drinks and said they enjoyed them, and all with the notable exception of B said they found the saline drink disgusting.

By contrast, B drank the saline solution with a pleased expression, saying it "tasted like pop." However, when he was asked to sip both a salty and a sweet drink and to continue drinking the one he preferred, he chose the sweet one and took a pass on the salty one.

The researchers concluded that B, like most people, has some fundamental preference for sweet drinks over salty ones-which goes far to explain why soft drinks have always been made with sugar rather than salt-even if he is unaware of the identity of either. In sum, it would seem that B has no preference for drinks unless he can compare them within the 40-second span of his memory.

What does this mean for us regular tasters? According to Adolphs, taste information "that is meaningless for an isolated individual stimulus can yield relative values when the taste is structured as a comparison." In other words, there's something in your brain that indeed has a preference for a sweet drink over a salty one, but there's something else in your brain that disgusts you when you're given a salty drink when you know you could've had a cola.

The research was supported by grants from the National Institute of Mental Health and the National Institute of Neurological Disorders and Stroke. The paper's coauthors are Daniel Tranel, Michael Koenigs, and Antonio R. Damasio, all of the University of Iowa's Department of Neurology and Neuroscience.

Source: CalTech

Explore further: Newlyweds, be careful what you wish for

add to favorites email to friend print save as pdf

Related Stories

Quantifying sensory data

Apr 02, 2014

Bite into a juicy pear or a spicy hot pepper, and thousands of electrical impulses race to your brain. Taste buds pick up signals for basic taste qualities like sweet and sour, and your tongue also senses ...

Astronomers open window into Europa's ocean

Mar 05, 2013

(Phys.org) —With data collected from the mighty W. M. Keck Observatory, California Institute of Technology (Caltech) astronomer Mike Brown—known as the Pluto killer for discovering a Kuiper-belt object ...

Reducing salt in crisps without affecting the taste

Feb 17, 2012

Food scientists have found a way of measuring how we register the saltiness of crisps which could lead to new ways of producing healthier crisps — without losing any of the taste. The research by scientists ...

New findings help explain our most mysterious sense

Feb 21, 2011

From your first sip of morning coffee to the minty zing of toothpaste before bed, your tongue is bombarded daily with a flood of flavors. How we disentangle and identify all those tastes is still pretty mysterious. ...

Gastric bypass alters sweet taste function

Nov 02, 2010

Gastric bypass surgery decreases the preference for sweet-tasting substances in obese rats, a study finding that could help in developing safer treatments for the morbidly obese, according to Penn State College of Medicine ...

Recommended for you

Newlyweds, be careful what you wish for

20 hours ago

A statistical analysis of the gift "fulfillments" at several hundred online wedding gift registries suggests that wedding guests are caught between a rock and a hard place when it comes to buying an appropriate gift for the ...

Can new understanding avert tragedy?

23 hours ago

As a boy growing up in Syracuse, NY, Sol Hsiang ran an experiment for a school project testing whether plants grow better sprinkled with water vs orange juice. Today, 20 years later, he applies complex statistical ...

Crowd-sourcing Britain's Bronze Age

23 hours ago

A new joint project by the British Museum and the UCL Institute of Archaeology is seeking online contributions from members of the public to enhance a major British Bronze Age archive and artefact collection.

Roman dig 'transforms understanding' of ancient port

Apr 17, 2014

(Phys.org) —Researchers from the universities of Cambridge and Southampton have discovered a new section of the boundary wall of the ancient Roman port of Ostia, proving the city was much larger than previously ...

User comments : 0

More news stories

Newlyweds, be careful what you wish for

A statistical analysis of the gift "fulfillments" at several hundred online wedding gift registries suggests that wedding guests are caught between a rock and a hard place when it comes to buying an appropriate gift for the ...

Can new understanding avert tragedy?

As a boy growing up in Syracuse, NY, Sol Hsiang ran an experiment for a school project testing whether plants grow better sprinkled with water vs orange juice. Today, 20 years later, he applies complex statistical ...

Roman dig 'transforms understanding' of ancient port

(Phys.org) —Researchers from the universities of Cambridge and Southampton have discovered a new section of the boundary wall of the ancient Roman port of Ostia, proving the city was much larger than previously ...

Crowd-sourcing Britain's Bronze Age

A new joint project by the British Museum and the UCL Institute of Archaeology is seeking online contributions from members of the public to enhance a major British Bronze Age archive and artefact collection.

Scientists tether lionfish to Cayman reefs

Research done by U.S. scientists in the Cayman Islands suggests that native predators can be trained to gobble up invasive lionfish that colonize regional reefs and voraciously prey on juvenile marine creatures.

Leeches help save woman's ear after pit bull mauling

(HealthDay)—A pit bull attack in July 2013 left a 19-year-old woman with her left ear ripped from her head, leaving an open wound. After preserving the ear, the surgical team started with a reconnection ...