You will certainly hear some jazz influence and extended playing techniques. The second theme in the first movement, for example, has passages where the strings are played directly, not using the keyboard.
Through her husband Gubaidulina had contact with a circle of political dissidents. This was during the reactionary Brezhnev era when underground "samizdat" publications strove to communicate a sense of what was going on in the world outside the constrained world of official truth.
After the Piano Sonata she struck out on a more independent path, as she said in a 1992 interview:
Until then, I had wanted to write for the theater, to compose ballets, symphonies... But then I understood: no, absolutely not. I need to write miniatures, miniatures in a whisper. I picked instruments that have almost no sound. The harp, a quiet, gentle instrument; the string bass is purposely muted; the percussion instruments are also treated the same way, so that the score calls for very few sounds. It was from this moment that I realized that I would pay no attention at all to anybody else. I would do what I liked... That doesn't mean, of course, that afterward I only expressed myself in a whisper.The piece she is referring to is her Five Etudes for Harp, Double Bass, and Percussion, also from 1965:
It is as if the music is for ritual dances of previously undiscovered peoples living in unexplored regions--and aesthetically, that is pretty much what it is. I hear a bit of jazz, but I also hear passages that remind me of Canarios by Gaspar Sanz, the 17th century Spanish composer for guitar. For Gubaidulina this journey was an inner one, seeking greater depth. Instead of inventing more and more novelties, she saw her role as a filter, rather than a generator.