Nervous and easily stressed people are more likely to be scrooges when it comes to buying Christmas presents, a new study found.

Those who are disorganised, nervous, emotionally unstable, curious and interested in new things are cautious when it comes to splashing the cash.

But confident and emotionally stable people are the big spenders.

British and US researchers found those who are calm, conservative in interest and always plan ahead, are organised and hard working doll out the dosh.

Christmas time is when many retailers make up to a fifth of their annual profits so knowing the psychology behind what makes people spend could help boost sales.

Psychologist Dr Sara Weston at Northwestern University in Chicago explained: "In most Western countries, the holiday season has evolved from a time devoted to religious celebration and family to one that is associated with materialism, consumerism, and excess.

"Given the importance of holiday shopping to the broader economy, seasonal increases in holiday spending are widely studied in disciplines such as marketing and economics.

"However, the psychological factors underlying changes in spending behaviour over this period have received comparatively little attention.

"This is surprising, as individual differences are likely to shape how people react to

holiday-related environmental stressors in terms of their subsequent financial behaviours.

"For example, the holiday season is often a time of increased stress, and psychological stress reduces self-control which may lead to excessive spending."

Dr Weston added: "We've known for a while that personality is related to what we call 'broad outcomes'.

"These outcomes include 'how much money you make' or 'how happy you are' or 'how long you live'.

"But we know less about why personality is related to those things."

Together with researchers from University College London they analysed more than two million individual transactions from 2,133 participants - who were split among five personality types.

These included 'openness to experience', 'conscientiousness', 'extraversion', 'agreeableness', and 'neuroticism'.

Results suggested confident people fork out more during Christmas - while nervous people spend less.

Emotionally stable people were said to be "untethered by the pressure and fear of disappointing others."

Low openness and conscientiousness were directly related to higher spends, while neurotic participants often coughed up less.

In addition, those with more active imaginations, or those higher in openness, spend less during the Christmas season.

It was found that people high in openness are typically low in traditionalism - making them less inclined to fork out on gifts.

The study also revealed that more conscientiousness consumers spend more than their seemingly careless counterparts.

This suggested the specific spending behaviours could impact broad outcomes - such as financial goals.

Co-author assistant professor of consumer behaviour Joe Gladstone, at UCL, said: "We provided objective measures of both annual and holiday spending for our data.

"This allowed us to carry out a truly ecological study of the relationship between personality traits and consumer behaviour."

The research provides a 'road map' of how combining large scale information with personality can provide a 'big picture' view of consumer habits.

Dr Weston added: "These results improve our understanding of how different personality traits predict how people respond to the environmental demands of the holiday season.

"They have broader implications for how personality relates to consumer behaviour."

The experts emphasised that personality is only one small part of consumer habits - especially at the individual level.

From household size to income and many other factors, the researchers stressed there are further influences at the individual shopping level.

The experts hope their study will be of use to retailers and individuals looking to understand and control spending habits.

Professor Gladstone added: "Our findings highlight potential predispositions which encourage or inhibit spending.

"This is important, as excessive consumption remains a major social challenge for modern society.

"Specifically, the expanding consumer debt burden created by excessive spending poses a risk to countries such as the United Kingdom."

Prof Gladstone said that half or more of UK household's report being unable to fund emergency expenses without seeking high-cost credit.

He added: "In this context, we believe there is benefit to even small gains in understanding who spends the most and why."

This study was published in the journal Social Psychological and Personality Science.