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CHARLES J. VELLA, PHD
OCTOBER 6, 2017
California Verbal Learning Test 3
CVLT 3
California Verbal Learning Test®, Third Edition
(CVLT®3) - Dean C. Delis, Joel H. Kramer, Edith Kaplan, Beth A. Ober
Overview: An assessment of verbal learning and memory deficits in
adults
Qualification Level: C (MA degree)
Age Range: Individuals 16:0–90:0
Administration: Digital (Q-interactive®), or paper-and-pencil
Completion Time: Standard and alternate forms: 30 minutes, plus 30-
minute delay.
Scoring Options: Q-global®
Publication Date: 2017
Users and applications
Clinicians can use the revision of this classic test to help:
Assess individuals who have been diagnosed with traumatic brain
injury (TBI), dementias, schizophrenia, ADHD, or neurological
disorders
Test the degree to which a person can return to work, perform complex
activities of daily living, and live independently
Evaluate insufficient effort or malingering to reduce false results
Content & Administration
Examinees are read a list of words carefully selected for their
frequency of use across multiple demographic variables and are asked
to recall them across a series of trials.
Standard and Alternate forms can be administered in 30 minutes, with
an additional 30-minutes for delay scores.
The Brief form features lists of nine words in three categories and can
be administered in only 15 minutes, plus an additional 15 minutes for
delay scores.
Features & Benefits
Full standardization based on education, region, ethnicity, and age
Additional scores allow for more in-depth analysis of errors (intrusions
and repetitions)
Available on Q-interactive and includes more robust scoring and
reporting: 50 variables scored
Upgraded and updated scoring and reporting on Q-global for paper
versions; if plan to hand score, read manual
CVLT 3
CVLT 3 is a revision of CVLT-II.
The target words for LIST A and List B of CVLT-II remain the same in
CVLT 3.
List A: truck, spinach, giraffe, bookcase, onion, motorcycle, cabinet,
zebra, subway, lamp, celery, cow, desk, boat, squirrel, cabbage
List B: violin, cucumber, elephant, closet, turnip, guitar, basement,
sheep, clarinet, garage, corn, rabbit, patio, saxophone, tiger, radishes
Cued recall categories: furniture, vegetables, ways of traveling,
animals
What's changed? = ***
New intrusion and yes/no recognition memory measures that enhance
the ability to distinguish between memory disorders
Modification of the forced-choice task to improve its sensitivity as a
performance-validity measure; no longer any abstract alternatives
Updated digital administration via Q-interactive® eliminates hand
scoring and saves time
Revisions in CVLT 3
Large updated normative database derived from national
standardization sample of 700, ages 16 to 90, demographically
matched to most recent US census.
*** New intrusion measures that enhance ability to distinguish between
the memory disorders associated with damage to subcortical-frontal
regions (white matter ischemic disease, Huntington’s) versus mesial-
temporal regions (Alzheimer’s, severe anoxia).
*** New yes/no recognition memory measures; again to differentiate
above
*** Modification of the Forced Choice Recognition task to improve its
sensitivity as a performance validity measure.
Revisions in CVLT 3
Option of administering in paper-pencil format or digital format via the Q-interactive platform; latter saves 15 minutes of scoring time.
For paper version, scoring software provided online via Q-global platform.
Use of scaled score metric rather than z-score metric for ease of comparison of test results both within CVLT 3 and with WMS-IV.
*** Introduction of index scores using standard score metric (mean = 100; SD = 15) to reflect performance on Trials 1-5, total delayed recall and overall recall.
Application of age-adjusted scale scores (mean = 50, SD = 10) for most measures
Option to use T-scores (mean = 50, SD = 10) that reflect education and sex adjustments to age-adjusted scores for several core measures.
CVLT 3 structure
Basic: Recall & recognition of 2 lists of words (List A & B) over a
number of immediate & delayed memory trials.
In first 5 learning trials, asked to recall 16 List A words (4 words from
each of 4 semantic categories) immediately after each presentation of
list. Words from same category are never presented consecutively; can
assess semantic clustering (most effective learning strategy)
An interference list B of 16 words is then presented for 1 trial. This is
followed by Short Delay Free Recall and Short Delay Cued Recall trials
of List A.
Structure
20 minute delay (do only nonverbal tests)
Then Long Delay Free Recall, Long Delay Cued Recall & Yes/No
Recognition next.
Optional (?) Forced Choice Recognition 10 minutes later: In both
Standard & Brief, Force Choice Recognition include only concrete
distractors (abstract distractors were not sensitive to poor effort)
Brief Form
4 immediate recall trials followed by 30 second distractor task.
Then Short Delay Free Recall of Word list.
10 minute delay
Long Delay Free Recall, Long Delay Cued Recall, Yes/No Recognition
5 minutes later a Forced Choice Recognition trial
Learning & Memory parameters measured
Levels of total recall & recognition on all trials
Learning strategies (semantic vs serial clustering)
Primacy-recency effects in recall
Rate of new learning per trial
Consistency of item recall across trials
Degree of vulnerability to proactive and retroactive interference
Retention of info over short and long delays
Learning & Memory parameters measured 2
Enhancement of recall performance by category, cueing, & recognition
Parsing of recognition performance (decidability & response bias)
Relative integrity of encoding, storage & retrieval processes
Intrusion error types in recall
Repetition errors in recall
False positive types in recognition
Test Scores (73 different scores)
Core Scaled Scores:
Trial 1 to 5 Correct
List B Correct
SD Free Recall Correct
SD Cued Recall Correct
LD Free Recall Correct
LD Cued Recall Correct
Total Intrusions
LD Yes/No Recognition Total Hits
LD Yes/NO Recognition Total False Positives
Recognition Discriminability (d’)
Recognition Discriminability Nonparametric
Base Rate:
Forced Choice Recognition Hits
Standard Scores
Standard Score: Score Range
Trials 1-5 Correct 45-155
[Trials 1-4 Correct]
Delayed Recall Correct 45-155
Total Recall Correct 40-160
Total Recall Responses 40-160
These are performances across multiple trials
Process Scaled Scores
Trial 5 Semantic Clustering
Trial 1-5 Semantic Clustering
Trial 1-5 Serial Clustering
Trial 1-5 % Recall Primacy
Trial 1-5 % Recall Middle
Trial 1-5% Recall Recency
Trial 1-5 Recall Consistency
Trial 1-5 Learning Slope Analysis
Trials 1-2 Learning Slope Analysis
Trials 2-5 Learning Slope Analysis
Trials 1-5 Recall Discriminability
Trials 1-5 Intrusions
SD FR Semantic Clustering
SD FR Discriminability
SD Cued Recall Discriminability
LD FR Semantic Clustering
LD FR Discriminability
LD CR Discriminability
Delayed Recall Discriminability
Delayed Recall Intrusions
Free Recall Intrusions
Cued Recall Intrusions
Total Noel Intrusions
Total Across/Within Trial Repeated Intrusions
Total Repetitions
Total Target Repetitions
Process Scaled Scores
Total Recall Discriminability
Cued Recall Discriminability
List A vs List B Recognition Discriminability
List A vs Novel/Prototypical Recognition Discriminability
List A vs Novel/Unrelated Recognition Discriminability
Response Bias
Response Bias Nonparametric
Contrast Scaled Scores
List B Correct vs Trial 1 Correct
SD FR Correct vs. Trial 5 Correct
LD FR Correct vs Trial 5 Correct
LD FR Correct vs SD FR Correct
LD FR Correct vs Recognition Discriminability
LD FR Discriminability vs Recognition Discriminability
Contrast scores = info on 1 type of memory trial while controlling for
performance on another trial measuring related more resilient memory
ability; replace savings scores
Base Rates (Cumulative Percentages)
Scores that have highly skewed, non-normal distributions provided
using base rates (% of examinees who obtain specific scores)
Base rate scores:
Cued Recall Novel Intrusions
Cued Recall Across/Within Trial Intrusions
Cued Recall Target Category Errors
Novel Intrusions/Total intrusions Ration
Novel Cued Recall Intrusions/Total Cued Recall Intrusions Ratio
Targets/Targets + Intrusions Ration
Targets/Targets + Target Repetitions Ratio
Base Rates (Cumulative Percentages) 2
List B False Positives
List B/Shared False Positives
List B/Nonshared False Positives
Novel/Prototypical False Positives
Novel/Unrelated False Positives
Forced Choice Recognition Hits
Recall Critical Items
Yes/No Recognition Critical Items
Noncategory intrusions
Across-List Intrusions
Synonyms/Subordinate Intrusions
Conditions with known memory deficits
• Neurodegenerative diseases,
i.e. Alzheimer's disease
• Depression vs. dementia
• Anterior temporal lobectomy
• Korsakoff's syndrome
• Huntington's disease
• Lacunar infarcts
• Stroke
• Alcoholism
• Left side complex partial
seizures
• Schizophrenia
• Encephalopathy from Lyme disease
• Tumors
• Anoxia
• Neurotoxic encephalopathy
• CTE
• ADHD, LD
• Medication effects
• Work capacity,
• Capacity to live independently
• Symptom validity
CVLT sensitivity
For predicting which nonclinical elderly genetically at risk for AD would
convert, or which MCI would convert to AD
Differentiation of subcortical (WM ischemic, Huntington’s, PD) vs cortical
(AD, severe anoxia, KS) diseases
Distinguishing between depression and neurological disorders, i.e. AD
Residual memory disorders due to TBI, neurotoxic exposure, chronic SA
Distinct memory profiles for schizophrenia, depression, psych. disorders
Degree to which person can return to work, perform ADLs, live
independently
Evaluation of symptom validity
Role of executive functioning in memory processes
If you are new to CVLT 3 Administration
If you have never administered this test, you need to read both the
manual and the administration form
Read the manual in order to understand how to score responses.
Give the test to a nonpatient first.
Basics
3 forms: standard (16 word list), alternate, brief (9 word list)
Admin. Time: 47-54 minutes
Software scored: 73 scores
Scores: age and gender corrected T scores (50 m, 10 sd)
age and gender corrected z scores (+5 to –5)
2 Word Lists, A & B, forced choice recognition, categories (furniture, veggies, ways
of traveling, animals)
Do not inform of later trials
Use only nonverbal tests in delay periods
Administration: standard responses
Avoid referring to the test as a memory or learning task when possible
“We’ll be doing some interesting things today. It’s important that you try to do your best. Some of the things we are going to do may be easy, and some parts may be a little harder. You’re not expected to get all of them right. Just do your best.”
“This is hard for many people.”; “Just keep trying your best.”
End of given trial: “Anything else?” Or “See if you can think of any more”
Don’t do CVLT 3 after another word-list memory test.
Repetition errors
Need to determine whether repetition is error or self cuing.
Repetition errors:
self cueing (don’t score) vs.
same confidence level (score);
if unclear, ask
If self cuing, do not record
If repetition is given with confidence, score as error
If unclear, can ask if they think response had been given before on that
trial. If “No”, repetition error; if “Yes”, regard as self cuing.
Development
List A and B word lists: target words not be highly prototypical of the
categories to which they belonged.
Individuals with confabulatory tendencies report intrusions that are
prototypical, and therefore are hard to identify.
Four most prototypical words from each category were excluded.
Same word lists A and B on both CVLT-II and CVLT 3.
All data collection was done on Q-Interactive platform. Study showed
equivalency of Q-Interactive and paper form.
Development 2: ***
Trial 3 to 5 instructions were shortened. “including words from the list you’ve said before” removed.
Instructions for Forced Choice Recognition shortened. No more “It may be difficult to remember which one to pick, but even if it’s hard for you, just try your best.” removed.
FCR trial instructions changed to tell them that they would hear 16 pairs of words.
All 16 of FCR distractor words were changed to concrete words.
Standardization
N = 700, based on US Census, ages 16:0-90.11, stratified by age,
education, race, region & sex
*** 3 new index scores: Trials 1-5 Correct, Delayed Recall Correct,
Total Recall Correct; and Total Recall Responses
*** Contrast Scores: adjustment of particular score based on
performance on another measure, i.e. SDFR dependent on ability to
recall Trial 5, controlling for forgetting rate.
Age corrected score to determine if level of delayed recall is high or
low for age
Contrast score to determine if level of delayed recall high or low for
immediate recall ability
Demographically adjusted scores
Age, Sex, & Education account for 30% of variance; but only age and
sex are adjusted for.
Age: explains 26% of variance; -.42 correlation; recall diminishes with
age
Sex: 5% of variance; females outperform males on many verbal
memory measures; recall 3 more words on 5 trials; .32 correlation
This is consistent with the hypotheses linking estrogen and verbal
memory performance, and that hippocampal atrophy is found in
younger men but not younger women.
Education: 4.5% of variance; 30% of NC with less than 12 years of
educ have impaired memory
CVLT 3 Reliability and Validity
Reliability data for the CVLT 3: alternate form reliability for each age
group; good at .73 to .83
Validity data for the CVLT 3 builds on the
CVLT-II and CVLT 3 are highly correlated
FCR no abstract word change: only 80+ showed more 15 or less
scores
Factor Components
5 Factors on CVLT 3: General Verbal Learning, Response
Discrimination, Organizational Strategies, Acquisition Rate, & Primacy
Recency Effects
It is suggested that a general verbal learning component consistently
accounts for about 35-40% of the total variance and consists of total
free recall over the five trials of list A, semantic clustering free and
cued recall (both short- and long-delays), and recognition hits.
A second, "response discrimination" component has also been found in
most studies. It accounts for about 8-10% of the variance with loadings
from free and cued recall intrusions and recognition false positives.
Test Scores
Mean = 100, SD = 15; range = 40-160, 4 SDs below and above mean
Higher scores indicate better performances
Contrast scores: adjusted scores, degree to which common variance accounts for performance of 1 score on related score; adjusts 1 score based on performance on another variable
Don’t use education corrected score with developmental intellectual disability; low education is effect of condition, not cause of low scores
Remember that formal education level may not be accurate reflection of premorbid IQ, i.e. 140 IQ person with 10th grade education
Base rates
Measure of rareness of findings; 9% = 9% of examinees in age group
had same or lower/higher score
100% = interpret performance in relation to those who made errors;
for most, associated with high base rate (normal, not exceptional);
for some age groups, perfect score may indicate above average
performance (check base rate with this age group that made one
error; if % is 75%, then 25% obtained perfect score, which is
exceptional)
Demographic adjustments
Don’t use education adjustment in ID who achieve limited education due to their ID
Don’t use in high IQ who stop school in 10th grade to help out family (use 16 not 10 years of educ)
Age-adjusted scores best used to describe level of cognitive skills, relative to age group, for decline due to neurological event, esp. for those in average range
Dx of ID or LD should always be based on age-adjusted scores only
Demographic adjustment
Demographic adjusted score helpful if:
(a) assess whether person’s performance on cognitive test represents an
acquired decline, esp. if premorbid skill are high or low for his age group
(b) education level appears to be accurate predictor of premorbid level
(c) you are not using scores to determine level of impairment for their age
group or to dx person with developmental condition (ID or LD)
Examples: high IQ with LH stroke, with age related DFR only in average
range, but demog. score is 1.5 SDs below average; no loss relative to age
group & no difficulty with ADLs, but there is a decline relative to premorbid
level & will have difficulty relative to other high IQ
Demographic scores
Scores near middle of distribution change very little, which means that
12 y of education will have little impact in terms of using demog. or age
scores
Largest effects are for individuals at extreme ends of demographic
group, highest or lowest; for high levels of education, demog. scores
will always be relatively lower than age scores; for low education,
scores will always be relatively higher. Scores tend to adjust higher for
males than females.
Demographic scores
If having a low score results in some benefit (get a service), potential to deny their benefit if they have lower level of education and demographic scores are used. Use age scores.
If having higher score results in negative consequence (death penalty), do not use demog scores, esp. if they have low education, esp. if due to LD or ID.
Demographic scores should never be used to dx LD or ID
See Delis (2009) and Holdnack & Weiss (2013)
Meaning of CVLT 3 Measures: Trial 1 Correct
Do not use terms “LTM” or “STM” in describing CVLT.
Trial 1 Correct: auditory attention (7 +/- 2); ave score = 6.5
May indicate ADHD, Anxiety, Depression if low
Anoxics do well on Trial 1 (good attention), but poor on other trials
Subcorticals may do poorly on Trials 1 to 5
Correlates significantly with Digit Span Forward:
if Trial 1 > DS = auditory sequencing problem (correct sequence
on Trial 1 but not DS)
If Trial 1 < DS = Depression, Anxiety; but ok on other trials
Trials 2-5
Trial 2-5: core verbal learning ability
Neurologically normal persons increase number of words
recalled with each new trial
Variability across the trials may reflect fluctuating emotions,
medication, pain, effort, or frontal damage)
*** Trials 1-5 Correct Index Score: global index of learning
ability; good score reflects good auditory attention and verbal
learning
Learning Styles: Semantic Clustering
Semantic Clustering: the words are drawn from four semantic categories (furniture, vegetables, ways of traveling, animals), with no consecutive words from the same category. If a subject 'clusters' words from a category together, it is probable that they are using semantic organization.
1 Semantic Clustering: consecutive recall of words from same category
Active imposition of an organization on list of words according to shared semantic features; more efficient encoding; mental filing system; occurs in encoding and retrieval
Active learning strategy; enhances recall
Low score = poorer recall
Declines in normal elderly, neurologically impaired, mood disorders
Declines in APO-e4 variant and predicts AD
Learning styles 2
2 Serial Clustering: recall in same order in which they were presented
Can indicate poor or superior memory
Usually high score = poor recall indicating stimulus bound recall
(using temporal order); often present in Parkinson’s (stimulus bound
in memory and EF deficit)
But occasionally indicates superior memory
Primacy/Recency Recall Scores
Serial position effect: Recall from different regions of original list: recall from beginning (primacy), middle or end (recency) of list
Primacy/Recency Recall:
Serial position effect
Normal: recall more from primacy (first 4) and recency (last 4);
primacy more likely because of more rehearsal time;
recency because can be echoed from STM
Easiest: recency high (can be echoed without encoding)
present in severe encoding deficit: AD, amnestic mild NCD, Korsakoff’s, focal left temporal/hippocampal lesions; some early AD will do ok on primacy due to rehearsal
Primacy/Recency Recall Scores 2
Average to above average recall of words from primacy and middle regions reflects strong learning skills (good encoding; correlate with LT storage))
Only results from Trial 1 can be considered pure primacy/recency effects.
Early Huntington’s: impaired free recall retrieval, but ok encoding; poor primacy/middle, but normal recognition memory
Rate of Learning
Learning Slope:
average # of new words per trial
1 = average of 1 new word per trial; > 1 = increase
Anxiety, depression: may perform poorly on Trial 1; may show above-average learning slope, esp. across Trials 1-2
Frontal lobe lesions; normal on trials 1 or 2, but reduced learning over 1-5, esp. 2-5; reach learning plateau or show inconsistent recall
Rate of Learning 2
Severe encoding deficit (AD, Korsakoff’s): no new learning; flat learning rate/slope; all 3 learning slopes are low
Parkinson’s Disease:
impaired level of correct on all 5 learning trials, but learning slopes are normal;
rate of new learning per trial normal; but overall level or recall below normal;
a retrieval deficit; better recognition relative to free recall
retrieval deficit - lowered level of recall on all trials, but produced normal learning rate
Recall Consistency
Percentage of Recall Consistency:
Recall of same words over trials
Low score (shift regions) = haphazard, inconsistency
Inconsistent in Frontal lobe pts., but not in AD (recall recency)
List B Trial
Proactive Interference (PI) = normal detrimental effect of prior on subsequent learning; Proactive Interference is normal. Expect fewer List B than A
List B is an interference list; shared categories: only two categories the same in Lists A & B (vegetables & animals); nonshared (musical instruments; parts of house)
Normal PI =
List B lower than Trial 1 due to interference from List A words
Recall of List B shared categories worse than nonshared categories due to semantic similarity to List A words
Recall of words from nonshared that is superior to recall from shared categories = release from PI (on Trial 1, normals recall same number of shared and nonshared; but on List B, recall shared decreases by 33%, nonshared increase by 21%)
Abnormal PI = if List B significantly lower
List B
Low contrast score = vulnerability to PI
Low list B and Trial 1 = poor auditory attention
AD lack of PI: higher list B
Short Delay Free Recall
Short delay free recall (SDFR): List A requested; recall on this may show decrement due to combo of short delay and RI from List B
Retroactive Interference (RI) = normal detrimental effect of new on previous learning
Scores for level of recall and retention (savings) of info from Trial 5. Level of recall after delay can vary from retention rate
Example: score of 6 on Trial 5 and SD = mild impairment in level of recall, but normal retention rate
Impaired recall level with normal retention rate: present in subcortical disorders (PD, HD, MS, HIV) and psych. disorders (depression, PTSD, ADHD, Schiz)
Significantly poor SDFR (low level and retention rate): present in cortical disorders: AD, Korsakoff’s, MTL damage
Short Delay Free Recall 2
Short Delay Score: low score = impaired short delay recall
Differences in performance across 2 or more recall trials (immediate or delayed) can be due to attentional fluctuation
To differentiate retention deficit vs attention problem:
Person with impaired retention rates likely to be impaired on Long Delay Yes/No Recognition; Person with fluctuating attention problem, but intact retention are more likely to perform better on recognition than recall testing
Person with poor retention rates on CVLT will do so on other memory tests; person with variable attention or effort more likely to show inconsistencies across several memory tests
Contrast Score:
savings from trial 5
low score = unusually rapid forgetting & RI
Short Delay Cued Recall
Short Delay Cued Recall: Category cues / semantic clustering
Asked to recall words from each of 4 semantic categories: gives assistance by naming categories & by use of semantic clustering for recall
If SDFR lower than SDCR, semantic facilitation; seen in MDD
Most neurological conditions that show retrieval deficits show equal SDFR & SDCR (both require retrieval) with normal recognition; category cues are not sufficient to overcome retrieval deficit & need recognition trial (which does not require retrieval) to show more encoded than retrieved
SD Cued Recall may impair recall in children with poor language skills; semantic categories may overload them
Short Delay Cued Recall 2
*** New Target Category Error Score: assist in determining whether linguistic categorization difficulties influence cued recall;
4 cues given; person may say zebra to ways of traveling;
not a memory error, but is linguistic categorization error;
scored as correct recall and Target Category Error;
those with higher number of latter may have lower verbal-intellectual skills
SDCR reveals tendency to make intrusion, or confabulatory, errors (words not on target list); SDCR pulls for this;
AD pts especially vulnerable to high intrusion rates on cued recall
Long Delay Trials
Long Delay Trials:
20 minute delay (use nonverbal testing); Low scores: high rapid forgetting rates
Purpose: measure forgetting rates over long interval & measure retention rate without an intervening list (avoid RI)
Several long delay measures of level of recall & retention ratio:
LDFR Correct: level of correct recall on LDRC trial
LDFR Correct vs SDFR Correct contrast score: how much info retained from SDFR to LDFR
Long Delay 2
Normally, LD trials parallels SD trials: Trial 5 to SDFR predicts normal retention from SDFR to LDFR; exceptions include attention or effort
LDCR can trigger intrusion errors, indicating most serious memory disorders
Two common memory deficit profiles:
Subcortical-frontal profile: Deficient level of recall on all trials, but normal retention of info learned over long delay; also in Psych. Pts
Cortical profile: Deficiencies in both recall level and retention rate over delay period;
seen in AD, Korsakoff’s, focal left temporal/hippocampal lesions;
mild forms of this in chronic alcohol abuse & conversion of genetically at risk to AD
Recall Error Scores: Repetition Errors
Repetition Errors: same trial repeats
Total Repetition score (repetitions on both target words &
intrusions in a trial)
*** New Total Target Repetition score: repetition of only target
words in a trial; not uncommon in normals as self cuing
HD: higher scores; repetition as perseveration
Other causes: poor encoding, source memory deficit
Recall Error Scores: Intrusion Errors
Intrusions: not on target list word
high score= low recall and recognition
Present in AD, Korsakoff’s, anoxia, hippocampal lesions
Detailed analysis of intrusion errors always warranted: presence,
degree, & nature of intrusions give differential dx of memory disorders
Intrusions: Immediate & Delayed Recall Intrusions
Immediate & Delayed Recall Intrusions:
Those with mild confabulatory tendencies can hold intrusions in
check during immediate recall, but produce irrelevant responses on
delay recall
Opposite pattern in impulsive and disinhibited: presentation of target
words on immediate recall can trigger loose association on
immediate recall, but not on delayed recall
Intrusions: Free vs Cued Recall Intrusions
Free vs Cued Recall Intrusions:
Originally CVLT included cued trials to provide intermediate level of retrieval aid for individuals with retrieval deficits (with maximum aide from recognition trials)
If locus of deficit is retrieval (i.e. subcorticals), category cues help
For most people, cueing significantly helps retrieval
Cued Recall trials elicit intrusions in those vulnerable to confabulation.
Increased intrusions on cued recall is one of most sensitive ways to detect preclinical phase of AD; with full AD, intrusions on both free and cued recall; but category cues result in markedly higher error rate than found on free recall
Intrusions: Across-List Intrusions
Across-List Intrusions: a List A word on List B trial (Proactive
interference), or List B word on List A DR trial (Retroactive
interference)
Disproportionately high number of across-list intrusions from either list
is considered to reflect a source memory deficit (can remember word,
but not source of word)
Synonym/Subordinate Intrusions
Synonym intrusion: Most benign intrusion error: report a synonym of
target word (i.e. ship for boat)
Mildly elevated number of these intrusions may indicate development
weakness in verbal skills, not memory per se; or a word finding deficit
Subordinate intrusion: word that reflects a specific example of target
word (i.e. red onion for onion)
Category Intrusions
Category Intrusion: nonlist word, but a semantic member of that
category (i.e. says car on List A recall, which has ways of traveling
category)
Small number of category intrusions occur with normal aging,
but high number may reflect confabulatory tendency in more
serious memory disorder
Often present in severe memory disorders in those with strong
language skills; AD, Korsakoff’s, with ok language, give
primarily categorical intrusions
Noncategory intrusions
Noncategory intrusions: most serious type of intrusion errors = one
that is semantically unrelated to categories on the list (i.e. says rock).
Can reflect both memory, attention, and language deficits
AD often present Noncategory words, as do Down’s syndrome (use
recency area, and then items in test room)
Can be a non memory issue: person with hearing problem
misperceives target word and gives phonemically similar
Noncategory word that rhymes with target word (flier for plier)or
gives part of target word (cabin for cabinet); may score these as
correct and note hearing problem in report
2 new measures: Novel vs Across/Within Trial Repeated Intrusions
*** A novel intrusion = person gives intrusion response for the first timeon any trial of test; it is an intrusion that they have not already given on current or previous trials.
i.e. dog on LDCR and not previously = scored as novel intrusion
Cortical Major NCDs (encoding deficits) produce higher proportions of novel intrusions
*** Across/Within Trial Repeated Intrusion: when person gives intrusion during a trial that is a word they have previously said on current trial (within trial intrusion) or on any previous trial (across trial intrusion)
dog on LDCR trial and also said dog on at least 1 of previous immediate or delayed recall trials; record as across/within trial repeated intrusion
Novel vs Across/Within Trial Repeated Intrusions 2
Subcorticals (PD, early HD, WM ischemia, focal frontal) have tendency to report high proportion of across/within trial repeated intrusions; some on immediate recall; frontals due to disinhibition of semantically associated words & source memory errors; frontals will often repeat initial intrusion repeatedly
Severe encoding cortical disorders (AD): propensity to confabulate (generate responses not on target list); issue of profound memory problem and relatively better, but declining, language ability, producing high intrusion rates across all recall trials, but esp. on cued recall where category clues elicit associations to those categories; but encoding deficit prevents encoding of intrusion
On 2 delayed cued recall trials:
Frontals continue to report any prior intrusion due to source memory problem; 58% ae across/within trial repeated intrusions;
AD pts: category cues elicit a surge of intrusions, 73% of intrusions are novel
Holden, et al., 2017
Yes/No Recognition
To validate whether individual has retrieval vs encoding deficit, need both free recall and recognition trials
To measure recognition, yes/no recognition trial (16 List A words & 32 distractors, with 4 types of distractors):
1 - List B shared Distractors (BS) – 8 list B, shared category (i.e. animals & vegetables)
2 – List B Nonshared Distractors (BN) – 8 list B from nonshared categories on list B, but not on A (musical instruments and parts of a house)
3 – Novel/Prototypical Distractors (NP) – 8 neither list, but prototypical members of categories on List A (carrot for vegetables)
4 – Novel/Unrelated Distractors (UN)– 8 not on either list, unrelated semantically (i.e. camera)
False Positive Errors on Yes/No recognition
False Positive Errors:
yes response to a distractor
High Score = significant memory disorder (esp. source memory); form of confabulation
Frontal effect
CVLT 3 has raw scores and base rates for each of 4 types of false positive errors (see slide after next)
False Positive Errors
Elevated false positive rate on recognition testing correlates with an elevated intrusion rate on recall testing; indicate confabulation
Early AD with depression: low intrusion rate on recall, but high false positive rate on recognition trial; depression reduces retrieval/intrusion; AD increases false positives
Verbally disinhibited: high intrusion on recall, low false + rate on recognition
Frontal: loss of instructional set results in strong yes or no response bias, a high false + or low hit rate
False Positive Errors on Yes/No recognition
1 - List B shared False Positives: shared category: most common type of error, due to source memory problem, semantic association, or encoding deficit that produces strong yes-response bias; also present in normal aging
2 – List B Nonshared False Positives: lack of semantic association, therefore more serious deficit; due to encoding deficit or source memory deficit
3 – Novel/Prototypical False Positives: more serious deficit; due to semantic pull
4 – Novel/Unrelated False Positives: most serious error; normal elders do not make them; cortical encoding disorders do
Recognition Discriminability
High recognition hit rate does not necessarily indicate good recognition; i.e. AD pts have yes response bias on recognition
Recognition Discriminability: ability to distinguish target from distractor words;
Discriminability Index = best measure of recognition memory (takes into account hit rate relative to false positive rate)
High, positive score = good recognition, encoding
2 measures of recognition discrimination:
Recognition Discriminability d-prime (d’): most commonly used recognition discriminability measure in NS research; range of +4 to -4
Recognition Discriminability Nonparametric
Recognition Discriminability
Advantage/disadvantage to both scores:
Very strong response bias in either direction (yes or no), d’ measure
better adjusts for fact that Yes/No Recognition has twice as many
distractor (32) than target items (16)
Number of false positive errors may be better reflection of impaired
recognition memory performance than false positive rate in AD, because
it is rare for them to endorse majority of 32 distractors; their relatively high
hit rate, combine with their medium false + rate, may translate to only
moderately impaired (not severe) recognition memory performance
Nonparametric index is based on absolute number of false + errors, may
better capture AD recognition severity
Correlation of d’ and nonparametric was r = .96
Response Bias
Response Bias: tendency to favor “yes” or no” recognition responses; negative raw score = yes response
-2 (strong yes) to +2 (strong no bias)
Severe encoding deficit: strong yes bias; high score = confabulatory
Depressed often produce strong no; often with derogatory comments
Frontals: can lose instructional set and favor yes or no; you can ask why & retest with Alternate form
Symptom Validity issues: can end with significant no responses
Recognition Discriminability subtypes
4 measures
1 – Total Recognition Discriminability: hit 16 targets, reject 32 distracters
Both d’ and nonparametric
2 – List A vs. List B Recognition Discriminability (formerly Source Recognition Discriminability): hit 16 targets, reject 16 List B
distracters; source memory disorders will do worse on this measure
Recognition Discriminability subtypes
3 – List A vs Novel/Prototypical Recognition Discriminability: – hit 16 targets, reject 8 novel distractors that are not semantically related to List A categories; those who have propensity to report primarily category intrusions obtain low score here
4 – List A vs. Novel/Unrelated Recognition Discriminability: hit 16 targets, reject 8 distractors that are both novel and semantically unrelated to List A categories; most severe encoding deficits exhibit low scores on this (and other 3 scores)
Encoding vs. Retrieval Patterns
Encoding: process of transferring sensory info into stored mental representation
Retrieval: process of bringing stored info into conscious awareness
Encoding vs. Retrieval Patterns: often based on FR vs Recog
Free Recall poor, Recognition OK = Retrieval Deficit;
words are encoded but there is retrieval difficulty
Free Recall and Recognition poor = Encoding Deficit;
if equal levels of impairment, then encoding deficit; recognition trial tests limits of what’s stored in long term memory; good measure of encoding
Free Recall & Recognition poor, but Free Recall significantly worse than Recognition; (i.e. 4 SDs vs 2 SDs)
Both encoding and retrieval impaired
Encoding vs. Retrieval Patterns
Tests of only FR exaggerate memory deficit in those with retrieval
deficit but normal encoding; fail to discriminate normal recognition;
tests that evaluate only recognition memory minimize memory deficits
of these same types if pts, because perform normally on recognition;
need recall test to show that they do not have intact memory but have
retrieval deficit.
Long Delay Free Recall vs. Total Recognition Discriminability:
Retrieval profile: low LDFR and OK Recog. Discrim.
Encoding profile: equivalently impaired on both
Encoding vs. Retrieval Patterns
Parkinson’s:
ok semantic memory (WAIS Voc or BNT), but only when retrieval
demands are not taxed (without time limits);
but on FAS (need fast and efficient retrieval), PD has deficit
PD semantic memory has ok storage or remote verbal klg, but
retrieval is impaired;
Episodic memory: ok encoding (intact recognition memory) but
decreased retrieval (free recall deficit)
Contrast Scores
Contrast Scores: for comparing performance on 2 trials or conditions of
a List; replace savings scores; using regression based method; obtain
predicted score on dependent measure based on variable for which
they wish to control (i.e. Predicted SDFC controlling for Trial 5)
*** 6 new contrast scores:
1. List B vs Trial 1 Correct: List B can be longer than Trial 1 due to PI
for learning trials
2. SDFR Correct vs Trial 5 Correct: SD can be lower due to RI & rapid
forgetting
3. LDRF Correct vs Trial 5 Correct: LDFR can be lower due to RI &
forgetting over delay
Contrast Scores
4. LDRF Correct vs SDFR Correct: LD lower due to forgetting over long delay; in some LD higher than SD due to provision of category cues on SDCR trial; helps semantic clustering
5. LDFR vs Recognition Discriminability: assess disproportionate improvement on delayed Y/N relative to FR; subcortical frontal show this; suggests encoding/storage deficit; this profile at severe level:
chronic alcoholic, LT epileptic exhibit this to lesser extent;
high altitude hypoxemia;
unusual pattern = significantly lower Rec. Discrim relative to LDFR – loss of instructional set, haphazard responses – found in poor effort; lower hits on recognition & low delayed recall; will produce atypical lower recognition than FR
Contrast Scores
6. LDFR Discriminability vs Recognition Discriminability: for those with
high intrusions on LDFR; more accurate comparisons
Recall Discriminability vs Recognition Discriminability
Recall Discriminability: correct recall level on particular trial relative to intrusions on recall on that trial
Recognition Discriminability: hit rate relative to false positive rate
On cued recall, AD free association to category cures & report many intrusions; some of by chance; not from memory but from semantic klg base
Total Recall Discriminability: development to correct for this (correct level of recall artificially high due to high intrusion rate; correct recall of targets relative to intrusions = more accurate measure of recall accuracy
HD and AD did not differ on recall, but significant difference on TRD with HD showing superior recall because high intrusion rates factored out in AD
Global Verbal Learning & Memory Indices
*** 3 new indices that reflect global measures of overall learning and memory:
Trials 1-5 Correct: global measure of immediate recall performance
Delayed Recall Correct: global measure of delayed recall performance
Total Recall Correct: global measure of performance on 10 core learning and recall trials
*** Also Total Recall Responses: sum of all raw correct and incorrect responses across 10 recall trials; global assessment of response activationindependent of response accuracy
AD have normal response activation but severely impaired accuracy
Severe depression limited response activation with high response accuracy
Assessment of Performance Validity
Memory functions are among most common areas in which individuals feign brain damage to look impaired; CVLT is good at detection of exaggerated memory deficits
4 embedded variables are sensitive to detection of memory deficit exaggeration:
Trials 1-5 Correct
LD Cued Recall
Yes/No Recognition hits
Recognition Discriminability
Unusually low scores in face of insufficient documentation of neurological involvement are alerts for insufficient effort or psychosis
Forced Choice Recognition
FCR: choose word from each pair that was on List A
A good measure of inadequate effort that is more blatant; in absence of dementia or psychosis
94% of norm group got perfect scores; 1 error is suspect
Poor forced choice indicates poor effort, but OK forced choice does not rule it out
List of Critical Items
Critical items: Inconsistences in memory of same target words across different recall & recognition trials; word should be recalled on easier FCR because remembered earlier on more difficult recall or recognition
Words remembered earlier, but not on forced choice; Extremely rare in norm group
Subtypes and Variability of Performance Validity
More sophisticated fakers may do well on FCR but poorer on harder PV measures
Patterns to be aware of:
Inconsistences across different trials (high LDFR with poor scores on the 5 immediate recall trials
Atypical patterns of learning characteristics (high proportion of recall from primacy & middle regions with poor overall scores on immediate recall trials
Atypical neurocognitive profiles (severe impairment on WMS LM with normal performance on more difficult CVLT trials like LDFR
Inconsistencies in test scores or cognitive profiles across repeat evaluation that cannot be explained by dementia, mood, medical or pain sxs, or practice effects
Discrepancies between poor scores on NP tests and higher every day life functioning
Determining severe to profound levels of memory impairment
FCR can be used for both:
Performance Validity
staging severity of memory decline for both early and advanced AD;
Scores on immediate and delayed recall & Y/N recognition tend to fall
in severely impaired range, approaching floor effects
Early and advanced AD pts achieve mean Total Correct hit scores on
FCR of 15 and 13 of 16; despite recall & Yes/No approaching floor
effects, can achieve remarkably higher FCR
FCR is way of staging severity of AD in mild vs moderate vs severe AD
Subtypes of impaired memory profiles in specific clinical
populations
TBI: fall into subtypes of normal, mild and severe
3 types of PD: normal, primarily retrieval deficit, & primary encoding
deficit
HD: retrieval profile, encoding profile
Also in HIV, mild cognitive impairment, depression
All produce specific profiles of memory strengths and weakness (see
Chapter 6)
Brief Form of CVLT3 (old Short Form)
9 words, 3 categories, 3 words per category, 4 Trials, 30 second delay
(count backwards from100) then SDFR trial, 10 minute delay, LDFR,
LDCR, Yes/No Recognition, 5 minute delay, FCR
Can be used as screening tool or for moderate to severe brain damage
Less taxing
Can differentiate AD from Multiinfarct dementia
No process scores; no PI, across list intrusion, source recognition
discriminability scores included
Chapter 6: Review of literature of CVLT and CVLT-II, 1999-2017
Demographic Factors: age, sex, education
Age: strong evidence of decline for rate of acquisition, overall recall &
recognition discriminability with age; older make more recall errors,
stronger yes response, more False positives – in both healthy and
clinical groups; impact of age on memory increases exponentially with
age; correlated with dopaminergic decline; need age correction
Studies have found that older perform lower on: Trials 1-5 Total, SDFR,
SDCR, LDFR, LDCR, Recognition, False positives, Trial 1, List B; often
worse for males
Lit Review: Sex – Women superior
Sex: sex differences in favor of females; related to more efficiency,
semantically based learning strategies in women; sex is significant
predictor of all major C2 measures; sex difference in forgetting rates
(retention); need sex correction
Studies have found: LDFR has stronger correlation with hippocampal
volume in women; women outperform men on most CVLT-II measures;
better on Trial 1-5 Total, LDFR, semantic clustering; advantage
improves with age, and is present in Schizophrenic women
Lit Review: Education
Education: Education is significant predictor of verbal learning and
memory performance; those with higher education have stronger
memory performance; applies to Short Form as well
Studies have found that with higher education: better LDFR, List B,
Trial 5
Highest C2 performance is 4 x more likely to be college educates
Korsakoff’s Syndrome
Korsakoff’s Syndrome: profound memory deficits, report few cognitive
complaints (limited insight); poor performance on all memory indices;
poor retention after a delay; lack of improvement on recognition;
predominantly an encoding/storage deficit (similar to AD); often
referenced as diencephalic-hippocampal profile
4 Dutch studies of nondemented chronic alcoholics, mean age 56:
severe C2 deficits; LDFR predicts route learning (an explicit memory
task); worse performance on Total Learning, List B, LDFR, LDCR,
Recognition; flat learning curve; self report of cognitive complaints was
not correlated with C2 deficits (EF deficit)
Amnestic MCI and Alzheimer’s Disease
aMCI & AD: have largest number of studies; highly significant deficits
across C2 measures, including semantic clustering, primacy-recency,
retention/savings in these 2 populations; most common pattern –
NC>aMCI>AD on most measures; AD shows no significant
improvement on Recognition relative to recall, implying AD is encoding
deficit; CVLT is a preclinical marker for AD and is a strong predictor for
conversion of aMCI to AD
Learning characteristics: worse on Trials 1, 5, 1-5 (AD T5=4, aMCI =
10; NC = 13); AD has flat learning curve, lower semantic clustering in
aMCI; NC average 80% by T5 (twice as many as aMCI & AD); early
semantic clustering decline related to AD pathology & indicates
progression from aMCI to AD
Amnestic MCI and Alzheimer’s Disease
Recall characteristics: aMCI significantly worse on LDFR & LDCR; AD worse than aMCI; greater rate of forgetting, greater recall errors; recognition discriminability lowest in AD (NC retain 70% on LDFR, aMCI 15%, AD 5%); pattern of NC>aMCI>AD is universal on CVLT performance; aMCI shows lower recall, poor subjective memory ratings (but unrelated to C2 performance), poorer prospective memory
AD vs depression: AD lower on all indices; AD did best with recency region, poorer on primacy; NC and depression show classic U shaped serial position effect (higher primacy/recency, lower middle); AD has unique pattern for greater recency than primacy
AD vs LBD: NC better than both on all measures; AD & LBD same on LDFR, but AD lower savings and recognition, more intrusions on LDCR; NC & LBD show significant better recall, retention & recognition than AD
Alzheimer’s Disease
Recall & YN Recognition Discriminability in AD: 93% Y/N in NC, 67% in
aMCI, 63% in AD (chance = 50%); NC has significantly higher
recognition hits, fewer false positives, greater sensitivity (d’); aMCI &
AD do not differ
HD and AD: recall discriminability – both severely impaired; but on
recall discriminability, AD lower than HD, esp. in SDFR, SDCR, LDCR
Source recognition discriminability: HD & AD similarly impaired, but AD
worse on Novel recognition & Total recognition discriminability; novel
recognition decimates between the two.
aMCI and Alzheimer’s Disease
Clinical and research utility in aMCI and AD: Trail 1-5 Total is best
discriminator of conversion to AD; also for differentiating NC from aMCI
(90% sens /84% specif); LDFR is strong predictor for AD conversion; 4
recall measures predict AD conversion, esp. LD Total Recall; poor
learning, reduced recall and recall errors identify aMCI at 98%; LDFR
is best predictor of persistent memory deficits
Huntington’s
Huntington’s: have impaired C2 performance across number of measures;acquisition problems, more intrusions, better recognition improvement; HD profile is primarily a retrieval deficit (subcortical pattern; also seen in depression & schizophrenia)
HD: memory is attenuated in Frontal-striatal dysfunction, like HD & PD, esp. retrieval deficit; poor retrieval but better recognition; but not always same retrieval deficits; retrieval deficit profile (RDP) = recognition discriminability z score – LDFR score >=2; NC on RDP= <2; HD more likely to display RDP (HD = 37%; PD = 8%); HD more likely to benefit from recognition compared to DR than PD; RDP more likely in HD when at least mild global cognitive deficits
HD vs AD Recall discriminability: on FR & CR, confabulation can result in intrusions; with high intrusions, person may have higher recall of target items by chance; Recall discrim. = # of targets recalled relative to # of intrusions; HD had higher intrusions on SDFR, SDCR, LDCR
Huntington’s
HD had better scores on Novel & Total Recognition discrim than AD;
Novel Recog. Discrim. Is best decimator between HD and AD
HD worse on LDFR and discrim. Relative to NC and MS pts; HD worse
on all scores relative to NC, esp. if evening cortisol up and more motor
sxs
Parkinson’s
PD: PD performance significantly lower than NC on C2; esp. difficulty
with semantic clustering (more serial clustering); more intrusion errors
but only on cued recall; more source memory problems; PD is a
subcortical dementia, incl. pathways to Frontal-striatal cortex; but mTL
structures important for encoding; but differs from HD
Study results: PD worse on all C2 indices, esp. SDCR & LDCR; less
semantic clustering; bradykinesia (pegboard) & hypokinesis
significantly correlate with serial clustering; frontal and EF deficits
include lower acquisition and recognition discrim.; deficits are
prodrome for PDD; like Schizophrenia, PD is a retrieval profile
(retrieval deficit with improved recognition); first a retrieval deficit, but
then an encoding deficit in PDD
Parkinson’s 2
PDD vs LBD: LBD worse on all recall measures, semantic clustering,
intrusions, response bias, false positives, Yes/No; more perseverative
errors in PDD
PD vs NC: PD significantly worse verbal learning; lower recognition
due to higher false positives; less use of semantic clustering; LD & SD
measures correlated with hippocampal volume, esp. Left hippocampus
PD has more EF deficits (lack self initiated retrieval skills)
Traumatic Brain Injury: always use CVLT
TBI: C2 clarifies nature of learning and memory deficits in moderate-severe TBI; both encoding and retrieval deficits; decreased retention; C2 performance related to TBI severity; mild > moderate > severe TBI; in severe TBI, explicit/episodic memory deficit co-occurs with normal implicit learning and memory; 4 factor model = attention, learning efficiency, delayed recall & inaccurate recall
Study findings: reduced learning, semantic clustering, more PI; diminished consolidation, retention, retrieval; increased intrusions and false positives; heterogeneity of deficits due to TBI severity and lesion variability; more rapid forgetting; diminished consolidation but intact encoding/retrieval
Mild TBI: more PI; no difference from NC, but subtle attention deficit
Traumatic Brain Injury 2
Over 1 year: lower SDFR, LDFR, LDCR; encoding deficit, flat learning
curve
Over 3-5 years: dose-response relationship; as TBI severity increases,
C2 performance decreases
Moderate-Severe TBI: lower Recall, Recognition and Total Recall
discriminability; higher false positives; rapid forgetting
Schizophrenia
Schizophrenia: verbal memory deficit is a key characteristic of Schizophrenia, including at first episode; longitudinal static persistence of memory deficit; not a progressive neurodegenerative disease; the greater the sxs, more memory deficits; division of memory deficits into multiple subtypes = cortical/encoding deficit; subcortical/retrieval deficit
Study findings: 70 study, 1999, metaanalysis = poorer F and Cued recall over SD and LD, poor recognition; other studies: negative sxs related to memory deficits; early onset = fewer words recalled, poorer recall; some PI and lower forgetting rate, less semantic clustering, more intrusions, poorer recognition
Schizophrenia: typically a subcortical, retrieval profile type (poor recall, ok recognition); but 3 possible profiles = normal, subcortical, & cortical
Depression
Depression: MDD have memory deficits associated with higher
symptom severity, esp. at 1st episode depression; declines in SDFR;
subcortical memory problem, with EF deficits = retrieval deficits,
impaired recall but relatively intact retention rates and recognition
Study results: often recall deficit with intact retention and recognition;
& risk for AD; increased serial clustering with R hippocampal atrophy;
MDD associated with poorer FR, learning slope, SDFR, semantic
clustering; often EF deficits; AD more recency items, whereas MDD
more primacy than recency; recall from primacy is characteristic of only
cortical types; MDD sxs predict EF deficits but not verbal learning;
unlike MDD, anxiety has no correlation with less words on Trial 1-5
Performance Validity
Performance Validity: FCR is good stand alone for PV evaluation (90%
performance score);
score below cutoff highly predicts poor effort; although score above cutoff
does not rule out effort issues;
embedded C2 measures are also good = better for identification of
adequate effort than of inadequate effort; Recognition hits and
Recognition discriminability (d’) are best of these 4 measures
Study results: Critical items (items recalled earlier but not on FCR or # of
occurrences of endorsed items on Y/R Recog not identified on FCR); should
be able to recognize words they were able to freely recall on recall trials;
Review of 37 studies, n = 7575; failure on FCR defined as <=14 of 16; there
were 0 failures; C2 manual = <1% failure, including in clinical groups
Performance Validity: FCR
Differentiation: Psychotics: 4x higher failure rate; later AD had 6x
higher failure rate; moderate TBI, 5x; 13% in secondary gain TBI, only
4% in non 2ndary gain
If fail independent PVTs, failure on FCR is 50%
Sensitivity is .50; specificity is .93 for FCR; scoring above 14 does not
rule out PV issues; scoring below 14 is highly accurate in identification
of PV issue
Failing FCR is highly sensitive predictor of poor PV; passing it is a
strong predictor of adequate effort
Performance Validity - Critical Items
Critical item analysis (CIA): LDFR was not predictor of FCR or CIA
Normal performance on these measures cannot rule out PV issues, but
score below 14 are very unlikely in individual with adequate effort
Trials 1-5 Total discriminability, Recognition discriminability (d’), and
LDFR predict poor effort
Trial 1-5 single most accurate predictor of poor PV when <= 46
Frontal Lobe effects on memory
• Frontal cortex plays a strategic role in memory performance.
• Frontal lobe pts exhibit overall:
• poorer recall (fewer words): poorer acquisition
• increased intrusions, false positives
• reduced semantic clustering,
• impaired Yes/No recognition
• On intrusions, frontals endorse specific distractors: semantically
related words and words from list B
• Frontals have false recollections and poor source memory
• Inconsistent recall across trials characterizes patients with amnesia
caused by frontal lobe pathology
