1) Erratic 2) Herky jerky 3) On again off again 4) Spasmodic 5) Spastic 6) Sporadic 1) Intermittent 2) Irregular 3) Like a restless night 4) Like a restless sleep 5) Occasional 6) Recurring irregularly 7) Spasmodic 8) Sporadic 
• (a.) Full of fits; irregularly variable; impulsive and unstable.
Fit'ful adjective [ From 7th Fit .] Full of fits; irregularly variable; impulsive and unstable. « After life's fitful fever, he sleeps well.» Shak. -- 
[adj] - occurring in spells and often abruptly 2. [adj] - intermittently stopping and starting
interrupted adjective intermittently stopping and starting; `fitful (or interrupted) sleep`; `off-and-on static`
coming, appearing, acting, etc., in fits or by spells; recurring irregularly.
[Literary terms] occurring in spells and often abruptly occurring in spells and often abruptly[Intelligent words] occurring in spells and often abruptly