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Depression dampens sense of smell

Can’t smell the roses? Well, maybe you’re depressed, says a new study, which has found that the part of depressed people’s brain responsible for the sense of smell is smaller than normal.

The new finding explains why many psychological disorders such as depression, schizophrenia and seasonal affective disorder seem to suppress the sense of smell, and it has implications for the treatment of depression itself.

To reach the conclusion, researchers at the University of Dresden Medical School in Germany exposed people — 21 with major depression and 21 who weren’t depressed — to a chemical with a faint odour, gradually increasing the concentration until the volunteers could smell it.

The researchers also measured the volunteers’ olfactory bulbs — the part of the brain that gives us our sense of smell — using magnetic resonance imaging.
Non-depressed people were able to smell the chemical at significantly lower levels than the depressed volunteers. The depressed also had much smaller olfactory bulbs, on average by 15 per cent.

Cooked food helped humans evolve bigger brains
Scientists have suggested that cooked food is the reason behind humans’ big brains.
According to one controversial evolutionary theory, early humans developed a taste for cooked food around 2 million years ago, and this set in motion a series of changes that made us utterly different from any other animal.Now, scientists have presented fresh evidence in support of the idea — and it all comes down to how you chew.

Christopher Organ of Harvard and Brown University in Providence, Rhode Island, and Charles Nunn and Richard Wrangham at Harvard University had predicted that if humans are uniquely adapted to eating cooked food, then we should spend far less time chewing than other primates, as cooked food tends to be softer than raw food.
To test this, they gathered data from various primate species and looked at the correlation between chewing time and body size, taking into account how the different species were related to each other.

New species of monkey found in Amazon rainforest
A new species of monkey with a red, bushy beard has been discovered in the Colombian section of the Amazon rain forest, say conservationists.

A scientist first glimpsed Callicebus caquetensis — a type of titi monkey — in the 1960s.
But political strife in the southern Caquetá Province kept scientists away until 2008, when an expedition finally confirmed the bearded monkey as a new species.

The cat-size primate is ‘fascinating’ because it mates for life, an unusual trait among monkeys, said expedition leader Thomas Defler of the National University of Colombia.
Pairs are often spotted sitting on branches with their tails intertwined.A typical Caquetá titi couple has a baby every year, and the father handles most of the infant’s care, other than nursing, Defler noted.

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