Electroreception: Science Behind a 6th Sense

Last week, I visited the New England Aquarium here in Boston and learned that sharks possess a sixth sense. They detect their prey by sensing electrical perturbations (active electroreception). Many weakly electric fish also use passive electroreception in communication as I observed in passing the electric eel tank (audible meter measuring electrical output across a bar ranging from sensing to attack mode. Each pulse lit bars on the graphs with a deep bump; like tapping a microphone!).

How widespread is this sensory system in animals and how many variations of it exist? Like marine creatures that rely on magnetic fields for hunting and navigation, birds & bees (not kidding!) also seem to detect the Earth's magnetic fields as they migrate (magnetoreception). Is is possible that humans could still have some vestigal remnants of a similar sensory system? Even monotremes (ie platypus) are able to distinguish between dead and charged batteries without touching them. Although it is generally accepted in the scientific community that humans have only five senses (or none at all, depending on who you ask), electroreception is a relatively new field and we still have much to learn!

To read more about the science of electroreception, visit the following sites:

www.newscientisttech.com...

en.wikipedia.org...

en.wikipedia.org...

news.nationalgeographic.com...

jeb.biologists.org...

www3.interscience.wiley.com...

www.biology.iastate.edu...

www.parmly.luc.edu...

Certainly if any serious investigation is warranted in humans claiming to have some sort of "sixth sense", this is an obvious place to start looking!

[edit on 2-6-2007 by X-tal_Phusion]

Originally posted by X-tal_Phusion
Certainly if any serious investigation is warranted in humans claiming to have some sort of "sixth sense", this is an obvious place to start looking!

Why? People that claim to have a 6th sense don't usually describe seeing electrical fields.

True they do not but perhaps this is how the human brain integrates sensory input it is no longer sufficiently equipped to cope with. We are only begining to learn about neuroplasticity and how it adapts to injury and compensates for loss of function.

Given the prevalence of electroreception in murky environments where vision is not very useful, I would not expect to to retain all parts of this sensory system in its original form over extended periods of evolutionary time since there is little apparent selection pressure in our modern environment. However, it is possible that some remnants are left over from a more functional system possessed by a common ancestor we share with other more closely-related organisms. If birds were able to retain or regenerate (through direct inheritance or convergent evolution) a magnetoreception sensory system, is it really such a stretch to hypothesize the existence of such systems in more closely related, migrating organisms?

My point is that perhaps the brain's reliance on more heavily conserved senses is an attempt to translate sensations it no longer has the ability to translate logically. A rather puzzling phenomenon called synthesthesia involves the perceived mixing of senses. It has been studied extensively and involves triggering one or more senses through the excitation of another separate sense. Here are a few references in case you have not heard of it:
en.wikipedia.org...
web.mit.edu...
psyche.cs.monash.edu.au...
www.sciam.com...

Electroreception and magnetoreception are not senses like the five well-established human senses. In it's fully-developed form, it isn't sight per se and in a complete system, we cannot expect it to be percieved as sight, sound or anything else familiar to us. If all we have are the sensory leftovers from a degrading system (again lack of sufficient selection pressure to preserve it because it is somehow advantageous in competition to survive and reproduce), we may only be receiving half the message. Rather than leaving a sensory blind spot, the brain fills in the blanks in the best way it knows how; with our 5 remaining, evolutionarily-conserved senses.

It requires specialized body structures to sense them with any accuracy.

Do humans sense them? To some slight extent, and it varies from person to person. When I was doing computer support, I knew people who were sensitive to the humming sound from electrical wires. However, they could not (as a shark could) locate the wires precisely based on the information they got from the electrical fields/magnetic fields.

If a species of shark has this (has developed the cell structures for it), then every single member of the species will have it. While SOME humans are sensing something, it's not well developed because we lack the structures for it.

I certainly DO believe that humans have a sixth sense, and some are more "in tune" with it than others and there are many varieties, not just associated with navigation.

If it wasn't so, how come my sense of direction is so good.

I've driven into the middle of the countryside one evening to meet a stranger who had been recommended by a friend that could help build me a computer.

After heading for the town and getting to the rough location I was going to ask for directions.
The road was a very long, main road and I didn't bother taking a map. (All part of the adventure).
I pulled over and spoke to a gentleman leaning over his fence and showed him the address on the piece of paper I had.

He said "park there if you like". I was there! cool. Whether it's magnetic or not, I don't know. Comes in useful though!

I never feel lost, wherever I go, but then again, Saint Brendan (my name) is the saint of navigation (nautical).

There's also perception, another form of sixth sense. A feeling of thinking something's going to happen.

Attraction and opposition too, a feeling of being pulled towards or pushed away from someone or something.

I think sharks are so good at using their electroreception because they depend on it for survival and have an ideal medium to use it in (water).
We, on the other hand have evolved by depending on our other senses, so our sixth sense is more dormant or devolved or developed into other forms.

Interesting stuff, thanx.

p.s. thanx for links in your profile X-tal. I must update mine some time with my own.

I believe that every human has the ability to access and process things through electricity. The very nature of the universe is electric. Matter would not interact the way it does without electricity, with out the magnetism that results, without the transfer of energies.

Electrical activity is one of the most prevalent forces in the universe. Is it really a surprise that every single thing on this planet is effected by it? Its presence is found in our ecosystem; plants, animals, the oceans, the atmosphere, and yes, us. Our bodies are sent up for the biomechanical/elecrical tranfer of data between cells by default. Our brains sned that current and recieve that current, providing a endless loop of neuro-electrical transfer. No ability for the body/mind to govern itself with out the use of electricity.

My extended theories on the 6th sense have traveled to the notion that when you are able to govern consciously the electro thransfer in ones body, and are able to differentiate the forces of yourself from those that are around you, the ability to accentuate these receptions becomes greater. It also gives you the ability to judge the level of the disturbance, and maybe even give you insight into the nature of the disturbance ie; a bad event or good event.

The theories on this have been documented, and have grown into the zero point theories, and the electric universe theories....where information is contained in these fields and such, and is therfore able to be accessed given our default organic makeups, and has been the reasons behind intuition, psychic abilities, hauntings, idiot savants, and so on. Whatever information is in the universe, we like wise have in ourselves, should we be able to access this.

Thanks for the opportunity to speak....and a great topic if I might add!!!

Originally posted by DarkSide

Originally posted by X-tal_Phusion
Certainly if any serious investigation is warranted in humans claiming to have some sort of "sixth sense", this is an obvious place to start looking!

Why? People that claim to have a 6th sense don't usually describe seeing electrical fields.

Not entirely true. I can see radiation on a bright sunny day. I sometimes see cosmic particles, like spots and specks of bright light floating through the air in waves. This effect can be seen when looking into a microwave oven while in use.

Radiation can be seen. I have electromagnetic hypersensitivity. I don't have any light bulbs in my apt. I use candles, and it's not because Im cheap or poor and cant pay a bill. The lights simply bother me.

I like how Xtal talks about a sixth sense, and does not believe in fellow humans who claim to have these senses as well. Sharks might only have 4 senses. Just because they have a sense that is not relative to humans is irrelevent. Their special sense could only be a 4th sense. Can Sharks touch and feel? Do they taste anything when they eat besides blood?

Good topic though, I give you that respected foe.