NEW YORK — Have you had a good laugh lately? Anything funny happen to you this week? And, what types of jokes makes you chuckle the most? Such questions are increasingly the focus of scientific research — for evidence is now piling up that our sense of humor directly affects our well-being.

Despite the popular stereotype of grim-faced shrinks, psychologists have been interested in this topic for over a century. A landmark was Sigmund Freud's 1905 classic book "Wit and Its Relation to the Unconscious." In Freud's influential view, people often use humor as an indirect way to express feelings that would otherwise be blocked by their unconscious mind. A good example is sarcasm, which Freud correctly saw as veiled hostility. In his view, jokes allow our suppressed emotions to surface and be released — thereby ridding ourselves of inner tension.

It's well known that Freud himself had a good sense of humor, although it was often sarcastic rather than kindly or gentle. Having written prolifically about the presence of phallic symbols — such as church steeples and obelisks — ever present in everyday life, Freud was once confronted about his preference for cigar-smoking. His famous retort was: "Sometimes a cigar is just a cigar." On another occasion, Freud was asked by a colleague, "How can you sit there all day and listen to those dull patients with their boring complaints about their lives?" And what did Freud reply: "Who listens?"

Freud's long-time associate was Alfred Adler, the founder of what he called Individual Psychology. Adler emphasized the importance of humor for well-being — and warned that it's never good to take oneself too seriously. "I can't deny that I tease my patients," Adler once confided to a group of doctors at a training seminar, "but I do so in a friendly way and I always like to show through a joke what's happening in a case. It's very worthwhile that you have a great collection of jokes. Sometimes a joke can help the patient see how ridiculous is his neurosis."

Adler's famous protege was Abraham Maslow, a cofounder of humanistic psychology. He wrote extensively about humor among highly successful people — those whom he termed self-actualizing. In Maslow's view, such persons richly enjoy humor — but of specific kinds. They share an appreciation for life's absurdities and have an ability to banter easily, as well as to poke fun at their own foibles. They also shun telling — or even willingly listening to — jokes that are insulting, malicious, or cruel: that is, laughing at someone else's expense. In this light, it's fascinating that the Jewish Talmud declared more than 1,500 years ago that one of the three best ways to discern someone's true nature is uncovering their sense of humor.

Today, positive psychology is giving a lot of attention to humor. A growing body of research shows that having a healthy ability to laugh is an important aspect of our psychological well-being. Among the leaders in this specialty is Dr. Rod Martin of Canada's University of Western Ontario. For more than 25 years, Martin and his colleagues have studied humor styles and garnered clear evidence that people differ in the role humor plays in their daily lives.

Martin's work identifies four different types of humor:

Affiliative — which involves humor as an effective "social lubricant," such as in improving parties and other group gatherings;

Self-enhancing — which relies on humor to cope effectively with stress, and is a form of resilience;

Aggressive — which involves sarcasm and other hostile verbalizations to maintain a sense of superiority or entitlement;

Self-defeating — which centers around self put-downs and is the bulwark of countless comedians from early Woody Allen to the latest "Saturday Night Live" incarnation.

As you might suspect, the first two types of humor have been linked to good mental health and well-being. In contrast, the latter two types are associated with impaired functioning — such as chronic anger, feelings of unworthiness or incompetence, and depression. Can you change your habitual humor style to one that's more healthy and fulfilling? Though research is yet scanty on this question, the answer appears a definite yes.

How about cross-cultural stereotypes — like that Germans are unfunny or British have a dry sense of humor? It's well known in the movie industry that comedies are far more difficult to transport across national boundaries successfully than action-thrillers or romance — for humor depends so much on cultural context,involving taboos as well as cherished values.

In any event, humor today is clearly no laughing matter. Big Pharmacy is sure to fight it, but the day may come soon when your doctor will advise, "Have two belly-laughs before bedtime and call me in the morning."

Tips for developing a healthy sense of humor

Think of a friend or someone you know who has a good ability to see humor when difficult situations arise. Describe a memorable incident when he/she showed this ability.

Now think about yourself and the person you are: Do you think you are at all like this person you mentioned? If so, describe a stressful incident in which you found some humor: What was your joke or wit about?

There's scientific evidence that laughing strongly is good for your health. Describe the last time you had a real "belly laugh" — what were the circumstances? Who was with you? What can you do to have more belly-laughs in everyday life?

Over the next week, write about something funny each day that you see in daily life. To what extent did this activity improve your well-being? If it works for you, continue on an ongoing basis.