Talk about a dream, kill a conversation. Write about one and risk a more effective soporific than melatonin. Yet, even though cartoonist Roz Chast acknowledges that "Only shrinks are interested, and maybe not even them," she has written an entire book about dreams. And — no surprise — it's delightful.

She pulls it off because she's Roz Chast; even her subconscious emanations present deliciously skewed takes on life's absurdities and fraught moments. She keeps her accounts blessedly short — edited "dream filets," as she calls them — and enlivens them with her signature drawings of anthropomorphized chickens, crabby matrons, and animated vegetables.

She starts with a multi-prong plug for dreaming. Among her arguments: "It's free entertainment." "You don't need special clothes or equipment." "They are a nightly reminder of the mystery of consciousness." She reassures us, however, that she's kept "REM cycles and the biomechanics of sleep out of this book because it's interesting to me, but not all that interesting."

What is interesting to her is that even though she's the one whose brain is creating her dreams, they always surprise her.

What's interesting to me is that while her eight categories of dreams include Nightmares and Body Horror, she doesn't explicitly flag Anxiety Dreams. There are times when I wonder if there's any other type.

It turns out, the majority of Chast's dreams — whether Recurring, Lucid, Celebrity, Nightmare, Horror, Food, or Everyday — are, as one would expect for a self-declared anxious person, ridden with angst.

There are classic recurring dreams like panic over a lost car, a lost purse, lost in high school, lost in a strange city, lost teeth. (There are a lot of dreams about dentistry, including one that involves Henry Kissinger.)

There are disturbing visits from her long-dead parents. One features her father's skeleton, which has shed its uncomfortable skin. In another, her mother is wearing an apron printed with cuts of meat. There's a dream in which Chast is riding a bus topless, and no one cares. Equally alarming, one features the author "Pregnant and OLD." Noticeably absent, along with dreams about trains entering tunnels, are dreams about sex.

Unlike most people's dreams, many of Chast's have hilarious punchlines. A mother-figure tells her, "Rozelah, ir zol koyfn Google lager" — which, she explains, is Yiddish for: "Rozzie, you should buy Google stock." When trinkets and beach glass tumble out of her mouth in another dream, a "fancy rich lady" says, "Maybe you can sell some of it on eBay."

Cartoon ideas also seep into Chast's dreams, most of which she deems unpublishable, filled with bad puns — such as a horror pic called Stop and Chop. She writes, "I kind of like them anyway. I bet podiatrists have weird dreams about bunions."

Chast follows a survey of her own cockamamie dreams with a somewhat less entertaining but impressively succinct and mercifully brief tour through "Dream-Theory Land." She sums up various beliefs about dreams through the centuries: messages from the gods, predictors of the future, responses to our sleeping body's sensations, and ways the brain sorts itself out, pruning and discarding the superfluous.

She also cuts to the chase with Freud and Jung. Both men, she writes, believed that dreams "were the way that people could communicate with the part of themselves that lay in shadow during their waking hours." And how's this for an easy distinction? "For Freud, dreams were the realm of repressed wishes. For Jung, it was where people connected with the cosmic — the collective unconscious."

I Must Be Dreaming is obviously the result of a long fascination. Chast kept a dream journal as a teenager, which she picked up again after her kids grew up. She is particularly interested in the connection between dreams and creativity. In response to all the theories of dreaming, she suggests a combo-pack — a mixed-bag of explanations for why we dream. She illustrates this with — you guessed it — that most beloved of cartoonists' tropes, a pie chart. ("To me, a book without a pie chart is hardly a book at all," she comments.)

This isn't the first time that Chast has made light work of potentially heavy subjects. Most notably in her memoir Can't We Talk About Something More Pleasant?, she tackles mortality and her relationship with her parents. In What I Hate From A to Z, she chronicles particularly annoying aspects of her life. I Must Be Dreaming demonstrates that Chast has figured out a way to catch and release her dreams — transforming them in the process into yet another charmingly relatable book.