Does it happen with all the PSD files or a particular one? What are your system specifications (CPU, GPU, RAM, OS version)? If Mylenium's suggestion doesn't help, try resetting the preferences or After Effects and cleaning the media cache (Edit > Purge > All Memory & Disk Cache).
Reinstall AE and possibly also Photoshop. Also make sure to save your PSDs with maximum compatibility enabled. This looks like either PS is saving the files wrongly or one of the shared components for file handling is damaged.