Association is strengthened by similar content and content in the present. When two things are happening simultaneously the two may become associated. This will allow for someone to associate the two things in the future. The phenomenon of association can play an adaptive role, such that a friend eats some berries in the woods and within a few minutes dies from poison. You are more likely to remember what those berries look like and not eat them next time you come across them.
According to James, long term memory took hours to for it to be processed, but he also believed that decay is immediate. Long term memory is also called secondary memory, permanent memory, or indirect memory. The memories in long term are help indefinitely unless the memory is being decayed and unused. James had thoughts on the two types of memory but did not determine if the processes where the same or happened at same time and just took different time