Ever dipped into the ­biscuit tin then decided you've ruined your diet so you may as well eat the lot? Or thought that because you didn't get a promotion this year, you're destined for failure in your career?

You're not alone. Even the most optimistic person is not immune to negative thoughts, but for some, the destructive chatter of self-doubt can be relentless.

Psychologists now believe that just as feeling embarrassed can cause a physical ­reaction (blushing) so self-destructive thoughts can lead to ill-health, weight-gain, poor skin and misery.

Psychiatrist Dr Daniel Amen has spent a lifetime studying how thoughts influence our appearance, energy and diet success.

Scientists have discovered that the amygdala, a small almond shaped structure deep within the temporal lobe, is important to a rich and varied social life among humans. The finding was published this week in a new study in Nature Neuroscience and is similar to previous findings in other primate species, which compared the size and complexity of social groups across those species.

"We know that primates who live in larger social groups have a larger amygdala, even when controlling for overall brain size and body size," says Lisa Feldman Barrett, PhD, of the Massachusetts General Hospital (MGH) Psychiatric Neuroimaging Research Program and a Distinguished Professor of Psychology at Northeastern University, who led the study. "We considered a single primate species, humans, and found that the amygdala volume positively correlated with the size and complexity of social networks in adult humans."

The researchers also performed an exploratory analysis of all the subcortical structures within the brain and found no compelling evidence of a similar relationship between any other subcortical structure and the social life of humans. The volume of the amygdala was not related to other social variables in the life of humans such as life support or social satisfaction.

A new meta-analysis study conducted by Syracuse University Professor Stephanie Ortigue reveals falling in love can elicit not only the same euphoric feeling as using cocaine, but also affects intellectual areas of the brain. Researchers also found falling in love only takes about a fifth of a second.

Results from Ortigue's team revealed when a person falls in love, 12 areas of the brain work in tandem to release euphoria-inducing chemicals such as dopamine, oxytocin, adrenaline and vasopression. The love feeling also affects sophisticated cognitive functions, such as mental representation, metaphors and body image.

With its technologically advanced animated characters, the 2004 film The Polar Express was supposed to change moviemaking. Instead, it gave audiences the creeps. Reviewers dissed it as "the night of the living dead." Why didn't the audience perceive the characters as alive? Something, they said, was wrong with the eyes.

Now, a new study shows just how important the eyes really are when we judge whether a face is that of a living person or an inanimate object. And that ability, the researchers say, is key to our survival, enabling us to quickly determine whether the eyes we're looking at have a mind behind them.

"People want to see faces, and we're very adept at seeing faces everywhere: in clouds, a burnt piece of toast, even two dots and a line," says Christine Looser, a Ph.D. candidate in psychology at Dartmouth College and the study's lead author. "And it makes sense to be aware of faces," because they might be those of living, dangerous creatures, such as a grizzly bear. "But we also don't want to waste time on faces that aren't alive, that aren't attached to minds."

It's Christmas morning in the year of the Christian dispensation, 2010 and I'm finding that I'm hard-pressed to be Merry about much of anything. If you want to read something cheerful and uplifting about Christmas, stop now and go elsewhere.

Yes, I am more than thankful for my wonderful family and friends and the extraordinary good times we have together, and I know that I am blessed beyond all expectations I ever had for my life. But in a sense, that's part of why I am unable to feel "Merry" about Christmas.

You see, within the circle of my family and friends, we share common values and aims that are based on love and caring and sharing, and all around us we see a world where those values have been degraded and corrupted to the point that they are either no longer recognizable, or they have disappeared altogether. This is incredibly painful and even moreso because we know that the way the world could be is so different from what is, and that this "what is" will, inevitably, affect us personally.

When, as a result of being part of a loving, cohesive group of creative and intelligent beings, one realizes that such a group is surrounded on all sides by creatures in whom the rule of the jungle prevails - the strong dominate the weak, conflict and rule by thugs is the order of the day - it is really hard to feel very Merry.

The situation is so bad that I see no hope for humanity at large at all. Extinction of our race is the inevitable outcome and I am no longer the only person who thinks so; even some mainstream scientists and pundits have written as much. They don't seem to be able to put their finger on the root of the problem, tending to blame it on effects, not causes, but they feel the prickle of the hairs rising on the back of their neck, and they sense the wolf circling in the darkness.

A new study from the University of Haifa shows that within the private sector high levels of emotional intelligence empower positive attitudes towards the workplace and decrease negative behavior; however, the same effect was not found within the public sector.

"The results of this study emphasize the existence of significant behavioral differences between the private and public sectors. Executives intending to carry out reforms or implement management plans in the public sector should be well aware of these differences," explains Dr. Galit Meisler who conducted the study.

The research paper received the Outstanding Doctorate Award from the Israeli Political Science Association and was supervised by Prof. Eran Vigoda-Gadot. It surveyed 809 employees and managers within four organizations: two in the public sector and two in the private sector.

In what researchers call a novel 'mind-body' therapy, most patients in a study suffering from irritable bowel syndrome reported relief after receiving pills they were told contained no real medicine. A simple sugar pill may help treat a disease - even if patients know they're getting fake medicine.

The finding, reported online Wednesday in the journal PloS One, may point the way to wider - and more ethical - applications of the well-known "placebo effect."

"The conventional wisdom is you need to make a patient think they're taking a drug; you have to use deception and lies," said lead author Ted Kaptchuk, an associate professor of medicine at Harvard Medical School. And, Kaptchuk added, it seems many doctors do this: In one report, as many as half of rheumatologists and internists surveyed said they had intentionally given patients ineffective medication in the hopes it would have a positive result.

Kaptchuk, however, wondered whether the deception was needed. When he first tried to persuade fellow researchers to explore a sort of "honest" placebo, "they said it was nuts," he said. After all, didn't the whole effect hinge on people believing they were getting real treatment?

Really, it's not religious. It is merely the momentary pause of thought. It is as religious as the holding of breath as you dive under water, or the halt of stepping as you pause from a rapid pace. It's as religious as the not eating that sometimes happens between meals. It's as religious as summer vacation, the space between words, or briefly being between jobs.

Meditation is innately human, and certainly in simpler times gone by, meditation came easily to us. Sitting under a tree near the river, listening to the sound of water moving, I suppose thought naturally paused for a few minutes in peaceful, spontaneous harmony. Or while watching the magnificence of the stars emerging in the sky as the world grew dark and quiet, rest undoubtedly came naturally to the mind. Science now tells us that this kind of rest for the mind is healing to the body, and it also helps to rebuild brain tissue and prevent several psychological disorders, including Alzheimer's and ADD.

You're probably familiar with the insidious effects of stress on your sleep quality and its link to anxiety and depression. Now growing body of evidence suggests that stress can take a physical toll, too, damaging everything from your heart to your immune system. It may even shorten your lifespan.

"Chronic emotional stress can affect virtually every organ system in negative ways," says Dean Ornish, M.D., founder and president of the Preventive Medicine Research Institute in Sausalito, Calif. "But stress is not simply a function of what you do. It's also a function of how you react."

If the word psychopath conjures up serial killers Charles Manson, Jeffrey Dahmer and Ted Bundy, the reality is that the blood-and-guts brigade are unlikely to get you.

The bad news is that there's a sub-species that will not slice you up and savour the wet bits but they're a lot closer to home and, paradoxically, harder to spot.

There is a psychopath on your stoop, on the golf course, in your book club, at your school reunion, between your sheets, even, rather disappointingly, behind the pulpit. In business they suck in their acolytes like a grade five hurricane.

Take Brett Kebble. At the height of his power, 41-year-old Kebble was seen as a colourful character known for his flamboyant lifestyle, overt generosity and a championing of black empowerment.

Although there were dark mutterings about his unorthodox business methods while he was alive, posthumously it was Pandora's box.

Kebble was exposed in the ongoing and protracted court case over his execution as one of the century's major confidence tricksters who dealt with perceived threats -- in the one instance we know of, according to evidence presented at the South Gauteng High Court -- by organising a conveniently debilitating stay in hospital for the "obstacle".

'The role of sociopaths in business'

At an investigative journalism workshop at Wits University in August 2006 on the Kebble story, Martin Weltz, the Noseweek editor, remarked that he had "long been interested in the role of sociopaths in business -- conmen, people who have the most unbelievable skills, like selling fridges in the Antarctic. South Africa also has its own community of conmen in business and Brett Kebble was one."

Weltz used the term sociopath but psychopath seems more apt. Although the terms are often used interchangeably, some psychologists see a sociopath's crimes as typically disorganised and spontaneous, while a psychopath's crimes are well planned. For this reason, psychopaths are harder to catch. Kebble's organisation and reach point to the latter.

Psychopaths may be obvious in a postmortem of the results of their actions but spotting them before the destruction is not that easy. They walk into a room and scan your barcode in minutes, capturing your likes, dislikes, motives, needs and -- most gratifying for them -- your weaknesses and vulnerabilities.