The findings suggest the possibility that serial position effects can be used to identify people who are developing MCI. (2005) found a difference between MCI participants and controls in the pattern of words recalled on the CERAD Word List, which is a 10-word list presented in a different order on each of three trials ( Welsh, et al., 1994). 2006) found a normal serial position effect for MCI participants on a 15-word list presented in a different order on each of three trials. Bennett's group ( Bennett, Golob, Parker, & Starr, A. The limited serial position data available from MCI patients have been mixed. The diagnosis of MCI can be difficult because memory impairment associated with MCI is often in a transition stage between normal age-related decline and the more serious deficit associated with Alzheimer's disease. In the AD group primacy was impaired but not recency. Gainotti and colleagues ( Gainotti, Marra, Villa, Parlato, & Chiarotti, 1998) used the 15 unrelated words from the Rey Auditory Verbal Learning Test and compared mild to moderately demented Alzheimer patients with controls on the recency and the primacy for totals across 5 learning trials. As expected normal primacy and recency effects were observed for the controls. There was no difference in recall on trial one between the mild and very mild groups. When performance on the first trial of the CVLT for a mild AD group (MMSE 23.5) was compared with controls, the mild and very mild AD patients had a recency effect but no primacy effect ( Bayley, et al., 2000). The controls recalled the primacy and recency regions equally, while the AD group recalled recency > middle > primacy. Foldi and her colleagues ( Foldi, Brickman, Schaefer, & Knutelska, 2003) used the 16-word California Verbal Learning Test (CVLT) and compared recall total across five trials of primacy and middle regions of the list with items in the recency region. The lack of a primacy effect also is a defining feature of word-list learning in patients with Alzheimer disease ( Carlesimo, Fadda, Sabbadini, & Caltagirone, 1996). Patients with anterior temporal lobe resections show significant declines in recall from primary and middle portions of a word list, but not the recency portion, compared with preoperative performance ( Hermann, et al., 1996). Patients with amnesia from a variety of conditions show a recency effect but they poorly retain primacy items ( Carlesimo, Marfia, Loasses, & Caltagirone, 1996). Craik (1970) found that words in the terminal serial position were retrieved best in immediate recall but least well after a delay. However, Glanzer and Cunitz (1966) found the recency effect was removed when a delay of 10 seconds or longer filled with a distracter activity was imposed before recall. Baddeley and Hitch (1993) review data in which the last few words on a list are preferentially retained after a distracter activity or a prolonged delay, which would argue against a simple short-term memory explanation. Other interpretations of the recency effect have been proposed. The recency effect usually is attributed to information being temporarily stored in short-term memory, which lasts for approximately 20 seconds and has limited capacity. When using a one-trial learning paradigm, there also is no proactive interference from previous items. The usual interpretation of this robust finding is that the primacy effect occurs because there is more opportunity for rehearsal of items in long-term (episodic) memory. These preferential recalls are called primacy and recency effects. In cognitively normal individuals words at the beginning and end of the list are more frequently recalled than words in the middle ( Deese & Kaufman, 1957). Serial position effects are observed when a series of items, such as words, that exceeds attention span are learned.
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