Table 1.

Definitions and calculated values of the norm of the 32 California Verbal Learning Test (CVLT) indices in healthy subjects. Distribution of the indices: Recall [1,2,3,4,5,6,7,8]; Recognition measures [9,10,11]; Recall errors [12,13,14,15]; Recognition errors [16,17,18,19,20]; Organizational strategies [21,22,23,24,25,26]; Contrast measures [27,28,29,30,31,32].

		Definition	Mean (2 SD)
1	List A, trial 1	Measure of initial learning	7.8 (4.5)
2	List A, trial 5	Number of words recalled in trial 5	12.5 (4.8)
3	List A, total recall 1–5	Total number of list A words recalled over five trials	54.5 (19.4)
4	List B, recall	Number of list B words recalled during the immediate recall trial	6.5 (3.7)
5	Short delay free recall	Number of list A words recalled immediately after the list B trial without re-presentation of list A	10.6 (5.9)
6	Short delay cued recall	Number of list A words recalled when category names were provided	11.4 (5.1)
7	Long delay free recall	Number of list A words recalled after a 20-min delay of nonverbal testing	11.3 (5.4)
8	Long delay cued recall	Number of list A words recalled after a 20-min delay of nonverbal testing when category names were provided	11.8 (5.1)
9	Hits	Number of list A words identified during the recognition task that included 28 distractor items	14.6 (2.9)
10	Discriminability	Ability to discriminate targets from distractor items during the recognition task (%)	95.6 (8.1)
11	False positives	Number of distractor items identified as list A items during the recognition task	0.5 (2)
12	Intrusions, total	Total number of nontarget items reported on all free and cued recall trials of lists A and B	2.9 (6.8)
13	Intrusions, free	Total number of nontarget items reported on all free recall trials of lists A and B	2.1 (4.8)
14	Intrusions, cued	Total number of nontarget items reported on the two cued recall trials of list A	0.8 (2.6)
15	Perseverations	Total number of responses repeated on each trial, summed across all free and cued recall trials of lists A and B	4.5 (7.4)
16	List B: shared	List B distractors belonging to a category shared with list A words (fruits, spices)	0.3 (1.2)
17	List B: unshared	List B distractors belonging to a category not shared with list A words (cooking tools, fish)	0.3 (1.4)
18	Prototypic	Distractors that are very common examples of list A categories (e.g., apple)	0.1 (0.8)
19	Phonetic	Distractors with phonetic resemblance to list A words	0.1 (0.5)
20	Unrelated	Distractors without any relation to list A words (e.g., cigarette)	0 (0)
21	Semantic cluster	Ratio of observed to expected clustering in which the proportion of correct responses followed by another correct response from the same category is contrasted with the expected chance clustering	1.8 (0.8)
22	Serial cluster	Ratio of word pairs recalled in the same succession as presented in list A relative to serial ordering expected by chance	2.1 (2.8)
23	Recall consistency	Percentage of target words recalled in one of the first four trials that were recalled in the subsequent trial	0.8 (1.6)
24	Learning slope	Slope of a least-squares regression line calculated to fit changes in correct response scores across trials 1-5	1.1 (1.1)
25	Primacy recall	Percentage of total words recalled in trials 1-5 that were from the primacy region of list A (first four words)	0.3 (0.1)
26	Recency recall	Percentage of total words recalled in trials 1-5 that were from the recency region of list A (last four words)	0.3 (0.1)
27	Retroactive interference	Decrease in recall score between list A trial 5, and list A short delay free recall (%)	−15.6 (34)
28	Proactive interference	Decrease of recall score between list A trial 1, and list B recall (%)	−10.6 (64.2)
29	Storage	Decrease in recall score between list A trial 5, and list A long delay free recall	−1.2 (3.5)
30	Rate of forgetting	Decrease in recall score between list A trial 5, and list A long delay free recall	0.7 (2.8)
31	Improvement index	Recognition hits minus long delay free recall	3.3 (4.6)
32	Improvement rate	Increase in the number of correct responses between long delay free recall and recognition, expressed as a percentage of recall	36.4 (68.7)