NEW YORK (Reuters) - A paralegal, recently laid off, wanted to get back at the "establishment" that he felt was to blame for his lost job. So when he craved an expensive new tie, he went out and stole one.

The story, relayed by psychiatrist Timothy Fong at the UCLA Neuropsychiatric Institute and Hospital, is an example of the rash behaviours exhibited by more Americans as a recession undermines a lifestyle built on spending.

In the coming months, mental health experts expect a rise in theft, depression, drug use, anxiety and even violence as consumers confront a harsh new reality and must live within diminished means.

"People start seeing their economic situation change, and it stimulates a sort of survival panic," said Gaetano Vaccaro, deputy clinical director of Moonview Sanctuary, which treats patients for emotional and behavioural disorders.

"When we are in a survival panic, we are prone to really extreme behaviours."

The US recession that took hold in December last year has threatened personal finances in many ways as home prices fall, investments sour, retirement funds shrink, access to credit diminishes and jobs evaporate.

It is also a rude awakening for a generation of shoppers who grew up on easy access to credit and have never had to limit purchases to simply what they needed or could afford.

Instead, buying and consuming have become part of the national culture, with many people using what is in their shopping bags to express their own identity, from the latest gadgets to designer handbags.

For those who need to abruptly curtail spending, that leaves a major void, said James Gottfurcht, clinical psychologist and president of "Psychology of Money Consultants", which coaches clients on money issues.

"People that have been ... identifying with and defining themselves by their material objects and expenditures are losing a definite piece of their identity and themselves," he said. "They have to learn how to replace that."

Beth Rosenberg, a New York freelance educator and self-professed bargain hunter, said she stopped shopping for herself after her husband lost his publishing job in June.

She is now buying her son toys from the popular movie Madagascar for $2 at McDonald's.