Insomnia involves disruption of sleep initiation, maintenance, and/or overall quality, and may interfere with cognition. We evaluated here rodent insomnia models predicted to produce sleep disruption and interfere with sleep dependent memory consolidation (SDMC), assessed as performance on a spatial reference memory version of the Morris Water Maze (MWM). Rats were trained to remember platform location in MWM (Acquisition), and then exposed to 6 hrs of: 1) baseline (BL, undisturbed); 2) dirty cage change-induced insomnia (animal placed into a cage dirtied by another rat); or 3) double dirty cage change-induced insomnia (DDCI, animal placed into a cage dirtied by another rat, and then another three hours later). The animal’s memory for platform location was then immediately evaluated in a probe trial. Time spent in Wake, NREM, and REM sleep was significantly different between treatments. Post-hoc pair wise comparison between BL and DDCI revealed an increase in Wake and decrease in REM sleep. NREM episode bout number and duration significantly differed between treatments, and post-hoc comparison between BL and DDCI revealed an increase in NREM bout number and decrease in bout duration, indicating sleep fragmentation. Significance differences were noted for measures of water maze performance during the probe trial (total time in target quadrant and latency to target quadrant). A difference between treatments in total distance swam was not evident, indicating that motivation and swim speed did not confound performance measures. The DDCI model particularly fragmented sleep and attenuated memory. Of utmost important is the development of hypnotics that improve the sleep profile of the insomniac but do not impair cognition, including sleep-dependent memory processing. This insomnia model uniquely mimics acute insomnia, and may provide an animal paradigm to screen hypnotic treatments and evaluate effects on cognition. Merck MISP (PI McKenna), and salary support for RES from VA Merit I01 BX002774.