Tolerance is a diminished response to a drug. It can involve less of an effect with the same amount of a drug, or needing more of a drug to have the same effect. Withdrawal is the physical and mental symptoms that can occur when a person stops using a drug. Delusions are false beliefs that contradict reality. Hallucinations are false sensory experiences, such as seeing or hearing things that are not actually there. Both delusions and hallucinations may occur in psychotic disorders like schizophrenia. Delirium tremens are a symptom of alcohol withdrawal that can involve hallucinations, shaking, and severe confusion. 

Iconic and echoic memory are two forms of sensory memory, which momentarily stores information from our senses before it is encoded in short-term memory. Iconic memory is the storage of what we see, while echoic memory is the storage of what we hear. Both of these functions can be improved with selective attention.

Implicit memory refers to memories that do not rely upon conscious recall activities. Procedural memory is the type of memory that we use to do everyday tasks like tying our shoes or riding a bike. These activities do not require our conscious awareness of our previous attempts.

Explicit memory refers to memories that can be consciously recalled. Semantic memory is memory about facts, like that Alaska is the largest state in the U.S. The other types of memory listed are types of implicit memory, which cannot be explicitly recalled.

Short-term memories are stored differently than long-term memories. Short-term memories generally include quick observations, and are only stored for 10-30 seconds. Short-term memories must be processed and stored as long-term memory in order to be accessible for any longer period of time.

Mood-congruent memory is when we feel a certain emotion, and then are able to access memories during which we felt similarly. For instance, if we are feeling frustrated in an intimate relationship we are more likely to remember another event during which we felt that same way.

Information only remains in our short-term memory for about 30 seconds. At the end of this time, this information is either forgotten or transferred to long-term memory.

Mnemonic devices are memory aids that seek to improve recall of information. Chunking is a popular memory aid that involves organizing items into familiar, manageable units. 

Influential cognitive psychologist, George Miller, conducted a series of experiments in which it seemed that there is a "magical number seven," meaning that we can usually hold about seven items in our short-term memory at once. This has been supported by many studies, but also disputed among cognitive psychologists.

An episodic memory is a recollection of specific events, usually one's personal experiences. Remembering specific details is an example of semantic memory. Learning a skill, like tying a shoelace, is procedural memory. Mnemonic devices are a tool for remembering detailed information. Remembering words one doesn't understand through repetition is a prime example of rote memorization.