Pattern 1 extension is an extension of the minor pentatonic scale pattern which you already know. This extended pattern is also commonly used for improvisation. Note the arrows indicating ascending or descending slides.
Use the ascending slide on the way up the pattern and use the descending slide on the way down the pattern, as illustrated in the example below.
Practice playing pattern 1 extension in different positions on the fretboard and use it to improvise over the Rock and Blues Jam-Along progressions at the end of CD2 (page 216). Even though the above example commences on the 3rd fret, the pattern one starting note (for determining what position to improvise against a progression) is still the note on the 5th fret of the 6th string, so the pattern is still centred around the 5th position .