Lysergic acid diethylamide (LSD) is a hallucinogen, which means it alters the user's perception of reality and can cause psychotic symptoms. LSD use in particular can result in synesthesia, dissociation, and other hallucinogenic effects. Synesthesia is defined as experiencing one sensory experience through another sensory pathway (e.g. "seeing" music in terms of color). Contrastingly, amphetamine, cocaine, and nicotine are considered stimulants, because they speed up bodily processes. 

Alcohol and benzodiazepines can be a potentially lethal combination. Benzodiazepines are psychotropic medications commonly prescribed for anxiety. Both drugs are nervous system depressants, and they have been known to have increased effects when taken together. Another significant side effect of combining alcohol and benzodiazepines is blackouts.

Consuming opiates can result in small pupils, slowed breathing, loss of alertness, dry mouth, itchy skin, nausea and vomiting. Opiates include heroin, morphine, codeine, and other prescription drugs. Consuming alcohol and benzodiazepines can result in delayed reaction time, impaired memory and judgement, and slurred speech. Consuming cocaine can cause euphoria, increased energy, and loss of appetite. Marijuana use can result in relaxation, dry mouth, increased appetite, and red eyes.

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.