Even Monkeys in the Trees Do It : INTOXICATION Life in Pursuit of Artificial Paradise <i> by Ronald K. Siegel (E. P. Dutton: $19.95; 337 pp.) </i>

For the last several years our country has been in a state of alarm over drug use, and much speech-making and money-spending have ensued.

What all of this accomplishes is anybody’s guess, but it doesn’t seem to have had much effect on the use of mind-altering drugs, which continues apparently unabated.

Now comes Ronald K. Siegel, a psychopharmacologist (specifically, associate research professor of psychiatry and biobehavioral science) at UCLA, to tell us that the effort is not only hopeless but misguided to boot. In “Intoxication,” a fascinating, eye-opening book that challenges conventional wisdom, Siegel says that we cannot stamp out the use of these substances and, what’s more, that we shouldn’t want to.

Far from being unhealthy or dangerous, Siegel says, the use of marijuana, cocaine, LSD and other such intoxicants is healthy and natural. He asserts that the need to alter our perceptions of reality is a “fourth drive” experienced by all people--”as much a part of the human condition as sex, hunger, and thirst.”

“The fourth drive,” Siegel says, “is not just motivating people to feel good or bad--it is a desire to feel different, to achieve a rapid change in one’s state.”

Siegel’s book is a well-supported, well-argued manifesto on behalf of mind-altering drugs, which, he says, should be viewed as key elements in a healthy individual’s life. I can’t remember reading anything quite like this since the turn-on, tune-in and drop-out days of the 1960s.

The anti-drug tenor of our times “had prevented us from seeing pleasurable changes in the body or mind as fulfilling health needs,” Siegel writes. “It is time to rid ourselves of such notions and recognize intoxicants as medicines, and intoxications as treatments for the human condition. We must expand the definition of self-medication to include drug use for purposes of intoxication.”

Siegel’s argument is based on substantial scholarship. The first half of his book details the craving of animals for mind-altering substances. Not just laboratory animals--pigeons, rats, monkeys and the like--but animals in the wild also seek out plants containing psychoactive chemicals. Once they discover the pleasurable effects that such substances induce, they go to great lengths to continue getting them--just as humans do.

Many pet owners tell stories about their dogs or cats that like to drink alcohol, and sometimes you hear about a dog who accidentally ate an ounce of marijuana and then staggered around the house for a day or so. But those stories don’t compare with Siegel’s amazing catalogue of animals and hallucinogens.

In one ingenious series of experiments that he performed, Siegel devised a method for determining what hallucinations pigeons and monkeys were having when they were on marijuana. The method involved rewarding the animals for matching pictures with what they were “seeing.”

Pigeons under the influence of THC (the active ingredient in marijuana) consistently saw blue geometric patterns. Monkeys saw the same patterns. So did humans. In other experiments, animals craved morphine. Siegel writes:

“Pigeons became tranquil and sedate after injection (with morphine). They barely moved. As soon as the experimenter approached with a syringe a few hours later, the pigeons came to the front of their cages, wings flapping with excitement, and stood without further protest for their next injection. When cats were used as subjects, it was often necessary for the handlers to use trickery and force to avoid being bitten or scratched during the initial injections. Resistance vanished after a few injections and the cats would run to the experimenter, jump on his lap, and even lick his hand while waiting for the morphine.”

The book is chockablock with such accounts, and it also contains an extensive scholarly bibliography, which gives them credence:

* Spiders given LSD spin webs with asymmetric designs that are radically different from the standard.

* Guppies on LSD swim into the walls of their tanks and keep on swimming, apparently unaware that they are not getting anywhere.

* Rats given access to alcohol drink the most “in the hours just before feeding--the ‘cocktail hour’ effect--and just before sleeping--the ‘nightcap’ effect.”

* Cats apparently hallucinate on catnip.

Siegel uses the animal studies to support his contention that the desire to alter one’s mental state is a basic drive of all living things. “We share (with animals) the same motivation to light up our lives with chemical glimpses of another world,” Siegel says.

Siegel’s book will be controversial, but his perspective on intoxication as a fact of nature and not just of culture cannot be ignored. His book should be required reading for William Bennett, the nation’s drug czar.