Picture perfect
Human eyes just can’t sit still. Even when your gaze is fixated on something, they continue to move. These rapid movements, called microsaccades, had puzzled researchers for more than 40 years. In a new paper in the journal Neuron, researchers from Phoenix, Arizona, suggest these minute movements may in fact explain why your vision is so clear. “If our eye was perfectly still during fixation, the world would quickly fade from view due to the fact that the neurons in our eyes and brain quickly adapt to non-changing stimulation,” explained Dr. Susana Martinez-Conde, the lead researcher in the project.
-Mike Ghenu
Source: Neuron; St. Joseph’s Hospital and Medical Centre news service
Neanderthals: Not that dumb
It is commonly supposed that modern humans, with their greater intelligence, had better hunting practices that allowed them to out-compete Neanderthals. Anthropologists now report there was little difference in the hunting abilities of Neanderthals and modern humans. Instead, they suggest that better division of labour and other social factors that allowed humans to better use distant resources led to the Neanderthals’ demise.
-M.G.
Source: Current Anthropology
Jonesin’? Us too.
If you constantly cave in to your cravings when trying to quit drugs like cigarettes and pot, don’t beat yourself up about it: it could be your genes. Dr. Paul Kruzich at the Medical College of Georgia found that rats from two different genetic strains varied in how readily they succumbed to the whims of withdrawal. Kruzich hooked the rats up to cocaine dispensers, allowing them to self-administer the drug as they pleased. After two weeks he removed the coke and gave the rats a hit of another drug that blocked their glutamate receptors, which scientists have linked to withdrawal. Because glutamate receptors are built and controlled by genes (as is everything else in the body) Kruzich argued that the two genetically different strains of rat would react differently to going cold turkey and having their glutamates blocked. Sure enough, one strain seemed to cope well with withdrawal, while rats from the other strain searched high and low for a coke fix. Because of the hundreds of genetic differences between the two rat strains it may be a while before Kruzich nails down the genes that make a person prone to relapse. However the study does highlight that individuals can respond in many different ways to the addictive potential of a drug.
-Chris Damdar
Source: Psychopharmacology
