Below you can find the CHANGELOG:

GAMEPLAY CHANGES
* New Ability - Mind Bash: Ian can now utilize his mental powers to interact with the environment in more ways. This allows you to stun enemies, destroy various objects and even kill enemies when powered up to overcome obstacles.
* Sanity Changes: Now sanity, instead of recovering when it is below 35%, does not recover. Instead, upon reaching zero sanity, Ian’s nightmares surface to the real world and creating even more threats. These threats can be fought with brute force or can be avoided until Ian’s sanity recovers. Mind Fly no longer depletes sanity unless a Mind Bash is initiated. The amount of sanity Mind Bash consumes are reflected on the user interface.
* Using Mind Fly now creates a shield around Ian, making him bulletproof. This shield consumes sanity upon taking damage. Ian can however can still be interrupted by melee combat during Mind Fly.
* Improved Auto Aim


MAP CHANGES
* Most of the maps are tweaked in conjunction with the gameplay changes.
* Hotel no longer has the forced stealth mechanics. Instead a timer is triggered which its duration varies depending on the difficulty you are playing that demands you to kill all enemies within the area. This timer can be manipulated with the ability Time Perception.
* Parking Lot is revamped, containing new areas that contain action based puzzles that requires you to use Ian’s abilities, as well as cutting down the linearity of the previous version.
* Chessroom is revamped in a similar manner to the Parking Lot, adding tutorials to adapt the player to the changed mechanics, culling the tutorials in size.


STORY AND CINEMATICS
* Additional story items, voiceovers. 
* Some existing cutscenes were reworked and some cinematic sequences were converted to gameplay.


BUG FIXES
* Fixed button icons occasionally lingering on the screen.
* Memory optimizations are made to reduce unnecessary memory usage.
* Fixed various localization errors.


PACKAGING CHANGES
* Changes made to the filesystem to improve the loading times and patch sizes. This has a side effect of making this patch bigger.