The Kremlin's customary pre-summit lightening on human rights is on view. Evidently Andrei Sakharov's wife will soon be allowed to go abroad for the medical treatment that she has been seeking through her years of internal exile. Meanwhile, Moscow moved expeditiously to keep the fate of the Soviet sailor who jumped ship in New Orleans from becoming an inflamed public issue. On the eve of the last summit the Soviets exchanged five political prisoners for two convicted spies held in the United States. This is the pattern.

It is a pattern bound to trouble many people in the West. The evident Soviet purpose is to deflate human rights as a summit issue. This is easy for Moscow to do. It need only wave its wand over the likes of Mrs. Sakharov, wife of the celebrated dissident physicist, and Miroslav Medvid, who became a chance celebrity by jumping a grain ship. The Kremlin looks like a kindly godfather and a few flesh-and-blood individuals benefit.

Mrs. Sakharov may soon leave; it is implicit that her husband may later follow. Mr. Medvid got the opportunity to say, in a setting that an attentive Reagan administration found conducive to free choice, whether he wanted to stay or go home. It's a good thing, by the way, that the administration intervened firmly to ensure his choice after the Border Patrol twice returned the sailor to his ship without having reliably determined his circumstances and views.

The sad fact remains that, in the arbitrary Soviet system, no relief is available for Soviet citizens other than by Kremlin calculation. People who have felt that Soviet society would eventually mature in this direction have been repeatedly disappointed. The arbitrariness that allows Moscow to make a gesture now is the quality that has allowed it for years to deny Western human rights appeals on grounds that they are an interference in an internal Soviet matter.

The new Soviet leader, Mikhail Gorbachev, apparently would like to be known as a reformer. But he came up as a prot,eg,e of veteran KGB chief Yuri Andropov, and reform in the Soviet context has more to do with discipline than with individual rights.

President Reagan cannot disdain gestures, especially gestures that help real people. Nor can he appear satisfied by gestures to a token few. His test is to convey the widespread American conviction, which amounts to a political fact of life, that the way Soviet citizens are treated inevitably affects the readiness of Americans to improve relations with the Soviet government.