Synesthesia is a relatively rare condition, reported to occur in 1 in every 250 to 25,000 people,
although these estimates are not based on good scientific evidence and many researchers believe it
is more common than previously stated. It is probably best thought of as a family of related
conditions. Different neurological mechanisms may be responsible for different types of
synesthesia. Synesthesia, according to the Greek roots that make up the word, means "joined
senses." Some synesthetes seem to have "joined categories," e.g. a letter, word, or day of the week
prompts an automatic, instant impression of a color, shape, or taste which is totally unrelated to
the first item. Other synesthete may see sounds as colors or vague shapes or swirls, smell images,
or feel tastes as shapes pressing on his skin.

There is a wide variety of research currently in progress on many types of synesthesia. For
updates I recommend contacting one of the synesthesia associations or research sites linked above.
As a synesthete I am peripherally interested in new developments in the field, but as a family
physician I devote most of my time to keeping up on more serious medical conditions! Information
below may be outdated as theories evolve, and researchers are
strongly advised to contact
reputable organizations, active researchers, and search scientific and medical literature to learn the
latest on synesthesia.

People with synesthesia experience  a
consistent, involuntary, elicited sensory impression in one
sense or category in response to a triggering input from a different, unrelated sense or category.
Consistent means the same trigger always causes the same sensory impression. Involuntary means
it happens automatically, without the person's imagining it or willing it to happen. Some
synesthetes are able to ignore or suppress their impressions, however. Synesthesia may seem
stronger or weaker under different physical and emotional circumstances (stress, fatigue, illness,
Elicited means the trigger must be present in order for the synesthete to experience their
linked sensations. This is a major way that synesthesia differs from something like hallucinations,
which are not caused by anything actually in the environment and are thought by the patient to be
real phenomena. Synesthetes know their impressions aren't "real" in the typical sense of the world,
but they are vivid, and often associated with emotional responses as well. Synesthesia is a
perceptual phenomenon, since the trigger stimulus must be present in order to create the effect.
(Some synesthetes can trigger their sensation by thinking of a particular letter, number, musical
tone, etc.)

Triggers most commonly are letters or numbers, musical pitches or sounds, time units such as
years, months or days of the week, tastes, smells, touch, pain, etc. See Sean Day's site for a more
complete listing of forms of synesthesia. A specific trigger consistently produces a specific
sensory impression, such as a perception of color, texture, taste or shape.  Most synesthetes
describe very specific colors, textures, pressure sensations, etc. for their associated impressions.
These stay the same throughout their lives. Every synesthete has a different set of associated
impressions from every other synesthete.

Synesthetic sensations can either seem to be "out there" in the world, or experienced internally
(e.g. seen in the mind's eye). In my case, I have perfect pitch, and ever since childhood I have
associated colors with music pitches. The Brandenburg 6th Concerto playing on this page is the
color of the purple background (when the main chord is B flat). Also present are lovely splashes of
red, gold and other colors as the chordal structure changes. I sense these colors as real, but
internal-- in my mind's eye or somehow surrounding me with a "feeling" of red, gold, purple etc.  I
don't see them hanging in front of me. I recall arguing with friends in junior high orchestra about
whether Fs were red or green!

Synesthetes often experience their sensations from birth or early childhood, may have strong
emotional responses to things that trigger their synesthesia, and often feel synesthetic experiences
are pleasant. They do NOT consider this trait to be a disability, but think of  it as an added bonus
to their normal sensory perceptions. Many synesthetes are surprised to learn, during childhood or
adulthood, that not everyone senses the world the same way as they perceive it.

There are controversies in research about synesthesia. The location(s) in the brain where
synesthesia happens, and the activity in the brain that causes synesthesia, are under investigation.  
Synesthesia research may help us uncover some subtle and intriguing facts about the nature of
consciousness. Some investigators believe all infants might have synesthesia at birth, with the
majority of people losing their linked sensory associations as they grow older. However, since
some synesthesia is triggered by categorical stimuli such as numbers, letters, and musical pitches
which are gradually learned as a person matures, some people question is at what age such
synesthesia actually develops, since we obviously don't know numbers and musical pitch names
from birth.

Synesthesia is thought to run in families. Some authors believe it may be an X-linked autosomal
dominant condition.  Its genetics is actively under investigation, and some dispute this theory.
None of my family members seem to have it.

There are other phenomena common to synesthetes that are not strictly sensory but seem to have
similar characteristics to true synesthesia. Many people report having an intricate 2-or
3-dimensional mental map of time, or 3-D "time line." Some attribute gender and personality to

Synesthesia  has been previously reported as more common in women and in left-handed
individuals. It has also been thought by some that synesthetes may be more creative, and may have
better memory and reading ability than the average person. It is certainly also possible that only the
better educated have discovered that their traits have a name. Some synesthetes have difficulty
with mathematics, left/right orientation, and face recognition. It is not known if these traits occur
at a greater frequency in synesthetes than in the rest of the population, since many studies of
synesthetes rely on self-identified volunteer subjects and not on any type of community census..
Any statements about a "typical" type of synesthete should be taken with a grain of salt.

There are several intriguing books about synesthesia available.
Synaesthesia: Classic and
Contemporary Readings
, by Simon Bar-Cohen and John Harrison, explores much of the science
behind synesthesia. John Harrison's
Synaesthesia: The Strangest Thing is a very clear  explanation
of the phenomenon for the lay person (non-medical).
Bright Colors Falsely Seen: Synaesthesia and
the Search for Transcendental Knowled
ge, by Kevin Dann, explores some artistic and controversial
aspects of the condition, as well as some scientific review. Luria's
The Mind of a Mnemonist
portrays a case study of a very unusual man with a photographic (eidetic) memory. His vivid
synesthesia partially aided his phenomenal memory. Richard Cytowic's book
, The Man who Tasted
es, is another interesting case study of a man with an unusual type of synesthesia, feeling
shapes associated with tastes. Cytowic's other book,
Synesthesia: Union of the Senses was
extensively revised and republished in 2002. A thoughtful and meticulous review of many issues
surrounding synesthesia, it is an outstanding resource for those curious about the neurological
origins and implications of synesthesia. It has a good discussion of "time unit" synesthesia,
categorical synesthesia and some of the other odd types. Another recent book is Lynn Robertson
and Noam Sagiv's volume,
Synesthesia: Perspectives from Cognitive Neuroscience. Please check
Sean Day's site, Pat Duffy's site, synesthesia  associations, and links above for other articles,
publications or conferences related to Synesthesia

Since becoming aware in 1999 that this trait had a name, and learning more about synesthesia, I
have realized that, in addition to music, my letters, numbers, days of the week and months were
latently colored. I now mentally see numbers on license plates, road signs, etc. in synesthetic color
as well as in the color they're printed in. Attention to less vivid perceptions can help synesthetes
more fully appreciate their unique multisensory window on the world!

These are my color and pitch perceptions
C#/Db navy blue, somewhat metallic
D# yellow-green; Eb gold, metallic
E-bright yellow
F-crimson red, tending toward magenta. Very vivid and rich.
F# maroon, a bit redder; Gb maroon, slightly darker with a metallic tone
G brown-orange, browner the lower the note is.
G# orange-copper, not shiny, but bright. Ab metallic copper/brass.
A orange
A# magenta; Bb a beautiful royal purple--more violet, reddish-purple hue
B a very crisp black.

Days of the wee
Sunday light brown/tan
Monday light blue
Tuesday navy blue
Wednesday mustard yellow
Thursday oak brown
Friday white
Saturday black

0 clear like black ice
1 gray-white
2 navy blue
3 yellow, slightly orange
4 dark red
5 brown--light to medium tone
6 black
7 brown, a bit lighter than 5
8 gray-lavender
9 white

A reddish-orange                                               N-brown
B royal blue-black                                             O-black to clear (like zero)
C white                                                            P-white
D blue & gray                                                   Q-black/purple touch of gold
E bright yellow                                                  R-black
F brownish gray                                                S-silver
G orange-brown                                                T-brown
H forest green                                                   U-violet
I white                                                             V-light brown-tan
J brown                                                           W-steel blue & white
K orange-pink                                                   X-gray
L red                                                                Y-white, slight yellow
M brown (warmer than N)                                 Z-silver/whit

Months: January, February, March, April, May, June, July, August, September, October,
November, December. January, February, June & July aren't colored as strongly as other months.

Hope you've enjoyed this romp through my brain.  Check back as I modify this site!

Elizabeth A. Pector, M.D.
family physician, author, and left-handed, intelligent, creative, modest synesthete
!  :-)
Does your music look like this?
Some Synesthesia Links:
Synesthesia--Sean Day's site
For further information, contact:
Elizabeth A. Pector, M.D.
Dr. Hugo's Synaesthesia site
Spectrum Family Medicine
Dr. Cytowic's Synesthesia Page
Andrew Lyons' article on colored music
Synesthesia in Art & Science:
Syn Resource Center: Blue Cats & Chartreuse
Kittens--Pat Duffy (extensive links)
American Synesthesia Association
UK Synaesthesia Association
Edward Hubbard's Research Lab
Synaesthesia Research Group
Synaesthesia Research Centre
updated August, 2006
New! ABC News article on synesthesia Test yourself & your syn!

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