There are many common causes of memory deficit, also known as memory loss. Many people believe that memory deficit naturally happens as a person grows old, and while some forgetfulness is to be expected, a dramatic loss of memories is a sign of another problem. Alcohol, some drugs — often illegal — and untreated depression can result in memory loss. Dementia is also characterized by memory deficit, though the disease affects many other aspects of the brain. Lastly, a stereotypical but common cause of memory loss is injury to the head.
Due to alcohol’s destructiveness nature when consumed, it can cause both long-term and short-term loss of memory, especially when consumed in large amounts. When a person is drunk, his or her brain struggles with absorbing new memories, and some memories might never be stored in long-term memory. Once the person has slept off his or her drunkenness, the night before might be a mishmash of random memories or no memories at all. People who routinely consume large amounts of alcohol may also experience problems with short-term memory, meaning they cannot recall things that happened recently, have difficulty learning new skills, or both. Some illicit drugs have the capability of causing a memory deficit in much the same way.
Untreated depression can also lead to memory loss, most likely because it involves the same part of the brain. Like with aging, memory loss from untreated depression should be mild. For example, a person with untreated depression should not routinely forget who he or she is talking to or how to drive to a frequently visited cafe. It is not unusual to often forget small things, though, like the name of an acquaintance, the secondary ingredients in a culinary dished just learned, or the specifics of last week's events.
Dementia most often affects people older than 65 but very occasionally occurs in adults in their 30s and 40s. This disease is defined as a loss of cognitive ability. It interferes with memory, language, and problem solving and is usually irreversible and incurable. Often, people in their late 40s or younger who have memory deficit are actually suffering from untreated depression, not dementia.
Lastly, minor head injuries or concussion can cause memory deficit. Other symptoms might also present themselves, such as difficulty problem solving, inability to focus, and trouble performing simple tasks. All of these symptoms should be evaluated by a doctor due to their seriousness. Head injuries can be fatal if enough damage is caused to the right spot.