Define the concept of the “procedural” and the “declarative” memory according to Cohen's theory about long term memory, and explain how the two concepts differ from each other.

LTM (long term memory) can be divided into the declarative (explicit) memory and the procedural (implicit) memory. The procedural memory is nonverbal in nature and is responsible for our motor skills. It contains information about “how to do” something, for example how to swim. 
The declarative memory can further be divided into the “semantic” and the “episodic” memory. The semantic memory tells us “what” something is and allows us to tell the difference between a book, a tree, a bicycle and a banana. Finally, the episodic part of the declarative memory is responsible for storing information about personally experienced events (episodes) such as the first time you went to the zoo or what you had for dinner last night. Studies with amnesia patients have demonstrated that while ability to retain semantic and episodic information following an accident often suffers, the procedural memory often seems to remain largely unaffected.