Shattered Memories is being developed with the Nintendo Wii as the lead sku. This means the game is being designed to specifically to leverage the Wii's controls and capabilities, then ported over to the PlayStation 2 and PSP with tweaking to adjust for the system differences.
The control configuration for the Wii version heavily focuses on the motion control and the Wiimote's specific bells and whistles. The Wiimote can be used in a number of ways, primarily as a flashlight, but is also used to open doors, grab handles and interact with items.
For the PS2 and PSP versions, the motion controls will be mapped to the button and thumbstick based controllers. As the Climax Group are the same developer who crafted Silent Hill Origins for the PSP and PS2, it's a good bet the controls will be the same or similar.