Ricerc@Sapienza

We often think of memory in terms of mentally reliving prior events. Such conscious recollection is, of course, an important aspect
of memory and has been a traditional way that researchers have defined and studied memory (James, 1890). However, it is also
clear that we are sometimes influenced by past experiences in the absence of conscious recollection. When we carry out a
well-learned motor skill, for instance, playing the piano or swinging a golf club, we are certainly influenced by past experiences
of practice and training even though we typically do not recollect these specific events as we carry out the skill. Likewise, researchers
have long proposed that prior events might produce nonconscious effects on current behavior: “.vanished mental states give proof
of their continued existence even if they themselves do not return to consciousness.” (Ebbinghaus, 1885/1964, p. 2). Indeed,
Ebbinghuas’s famous savings measure was developed for this very reason – to allow the assessment of both conscious and nonconscious influences of memory. Similarly, the neurologist Korsakoff argued that in patients with anterograde amnesia memory for the
past can sometimes evince itself without conscious awareness. Korsakoff found that although these patients show little conscious
recollection of recent events, they nonetheless demonstrate classical conditioning. These learning experiences were not themselves
recollected but were still capable of producing robust conditioned responses. This was demonstrated in a more colorful way by the
Swiss neurologist, Edouard Claparede (Claparede, 1911/1951), who was also treating a patient with anterograde amnesia. Despite
the patient’s inability to consciously recollect recent events, Claparede suspected that she has some preserved memory abilities. To
assess this possibility, Claparede concealed a pin in his hand, giving the patient a painful pinprick when they shook hands. The next
time Claparede met the patient, he extended his hand to shake but she refused. When asked she could not explain her refusal and
showed no indication of remembering the prior, painful encounter with Claparede. When pressed for an explanation, she eventually explained her reluctance by saying that people sometimes hide pins in their hands as a type of practical joke. Clearly the patient
was influenced by the original encounter even though she could not recall it.