Memory plays a fascinating role in our lives. Complex brain mechanisms lead to two types of memories: implicit and explicit. Implicit memory encompasses learned habits like writing or riding a bicycle. In contrast, explicit memory is responsible for remembering important facts and figures like phone numbers or credit card details.
A sudden loss of explicit memory leads to amnesia, whereas in dementia both types of memory are lost
Remember Aamir Khan’s character, Sanjay, in the film Ghajini? Sanjay forgets whatever he learns in 15 minutes.
Although an exaggerated portrayal, it highlighted a type of amnesia known as anterograde amnesia. In this condition, individuals struggle to retain new information and consolidate short-term memories into long-term ones. Damage to the hippocampus is often the primary cause of this form of amnesia.
In another type of memory loss, retrograde amnesia, the person is unable to recall past memories leading up to the triggering event. Those affected struggle to remember significant people in their lives, as the brain faces difficulty retrieving stored information. Damage to the thalamus, hippocampus, and temporal lobe is often responsible for this type of amnesia.
Psychological trauma and brain damage due to diseases or injury are often the underlying causes of amnesia.
Skim through this infographic that describes the primary differences between anterograde and retrograde amnesia.