Menu
Modern Biology
Muscle Disease Gene Identified in Fish
Bird Flu Mutation Risk
Platelets Help Tackle Bacteria
Untangling The Model Muddle
Cloning - The Good, The Bad and The Ugly
Unpacking the Human Genome Project
Does a Hot Mint Still Taste Cold?
Do Bald Men get all the Girls?
Why Plants Make Caffeine
Turning your Brain into Blood - How Stem Cells Work
The Microchimera Mixture
Forgetful Flies - A tale of two halves (of the brain)
The Smelly World of Mice and Men!
How animals develop from an embryo
Ricin : The Secret Assassin
Why drink Wine ?
Genetically Modified (GM) Plants
Big Fish, Little Sea
Something in the Air
What's On The Menu ?
What is the purpose of sexual reproduction?
Therapeutic Cloning, and Stem Cell Research
What is Living in my Mouth?
Genes for Bigger Brains
  Forgetful Flies - A tale of two halves (of the brain)
The brain is probably the most fascinating yet impenetrable organ studied by scientists. One question that remains to be answered is why we have two halves to our brains, and are they the same? Indeed, you may have heard how different skills and behaviours can be attributed to "left brain" or "right brain" hemispheres. Furthermore the halves themselves are not physically identical. They are asymmetric (not symmetrical), with slightly different structures found in each side, although the basic design is the same. But is this asymmetry important? A team of scientists from France, led by Alberto Pascual, set out to probe this mental mystery. First, the researchers had to choose an animal to study and found that the humble fruit fly, Drosophila melanogaster, fitted the bill for brain research. Fruit flies are not known for being the Einsteins of the animal kingdom, yet they have brains which are asymmetric like our own. Pascual and his team discovered a small lump inside the fruit fly brain that is only found in the right-hand hemisphere (see figure 1, below). They called this the "asymmetric body" (or AB, for short). By looking for the AB in over two and a half thousand fruit flies they discovered that nearly 8% of normal flies actually have symmetrical brains, with an AB in both their left and right brain halves. And yet these symmetrically-brained flies appeared to be completely normal in all other physical respects. So did their double-dose of AB have any effect on their brain function ?

To find out, the scientists put the flies through their paces in a series of rigorous tests. First the team probed the flies' short term memories by exposing them to a specific smell, followed by an electric shock. After three hours, the flies were tested again to see if they remembered the association between the smell and the shock. Meanwhile, to test long-term memory, another group of flies were individually put through an intensive teaching programme comprising five sessions of smell/shock training with 15-minute rest intervals between. This second group of flies were tested again after four days. From both the short-term and long-term memory tests, flies were separated according to whether they had remembered the association or not. The brains of these flies were then investigated to see if they had symmetric or asymmetric brains by looking for either two or one AB. The results were striking: the flies with symmetrical brains had no significant long-term memory, even though they performed acceptably on the short-term memory tests.

What can these forgetful flies tell us about how brains work? Of course, there needs to be much more research to figure out exactly why and how a symmetrical brain leads to long-term memory problems. The next step will be to look at more a complex brain, such as our own, to see if there is a similar link. Brain imaging technologies such as MRI and PET scanning provide the best tools with which to explore how brain structure is connected to functions like memory. It would also be interesting to look at patients with long-term memory problems, to see if they had more symmetrical brains than their less forgetful counterparts. In the future, we can hope to discover more about our brain of two halves, and maybe even explain why some people just can't remember birthdays!
fiestas en mayo
Bigfoot: The Nitrogen Problem
A Traveller's Guide to Bed Bugs
A spider web's strength lies in more than its silk
Thai police bust Bangkok rare wildlife 'butchers'
Castaway lizards provide insight into elusive evolutionary process
Bouquet bargains trade off for life
18 endangered dolphins spotted off Borneo: WWF
Tiny primate 'talks' in ultrasound
Steroids control gas exchange in plants
Fossil cricket reveals Jurassic love song
Rhino dies after anti-poaching treatment in S.Africa
Lions adapt to winter at Canada safari park
Invasive alien predator causes rapid declines of European ladybirds
Not the black sheep of domestic animals
Coaxing a Shy Microbe to Stand Out in a Crowd
How the zebra got its stripes
Fruit flies drawn to the sweet smell of youth
FLORA AND FAUNA Genetic Rosetta Stone unveiled in Nature
Ultraviolet protection molecule in plants yields its secrets
Indian village relocated to protect tigers
Explosive evolution need not follow mass extinctions
Plants use circadian rhythms to prepare for battle with insects
Armenia culls wolves after cold snap attacks
The Developing Genome?
Tempur-Pedic Mattress Comparison
Chromosome analyses of prickly pear cacti reveal southern glacial refugia
Poachers slaughter hundreds of elephants in Cameroon
'Founder effect' observed for first time
Menu
A Blue Future For Global Warming
Hitchhikers guide to Science
The Art of The Barbecue
Lost your bottle?
A Crossword a Day keeps the Doctor at Bay
Bio-plastics: Turning Wheat And Potatoes into Plastics
Why Don't Woodpeckers Get Brain Damage?
Protein Origami: Pop-up Books & Nature's Polymers
The Science of Parasites
Synthetic Biology: Making Life from Scratch
Flies are creatures of habit
What is Love?
How do plants develop?
What IQ Tests Can't Tell You
What is the Weirdest Experiment Ever?
Humble Honey Bee Helping National Security
Southern Right Whales
The Ocean's Cleaners
Barnacles "mussel" in
Food Date Coding Decoded
Photorhabdus luminescens: The Angel's Glow
Evolution Through the Looking Glass
I'm a Civet: Get me out of here!
No Smoke Detectors in the Sea