ObjectiveTo compare the ability of the Computerized Test of Information Processing (CTIP) to detect impaired cognitive processing speed in patients with multiple sclerosis (MS) with a traditional 3.0 second Paced Auditory Serial Addition Test (PASAT) and the Adjusting-PASAT which allows for calculation of a speed score. BackgroundA primary cognitive deficit in MS is an impaired ability to process information quickly. Unfortunately, relatively few clinical tests effectively measure information processing speed. Of these, the PASAT is generally acknowledged to be the most sensitive, but use of this test is constrained by several factors. MethodsAll tests were administered to 30 adults with relapsing-remitting MS and 30 control participants. ResultsA series of analysis of variances revealed MS participants performed significantly worse than controls on the CTIP and the 3.0 second PASAT, whereas no significant difference was observed for the Adjusting-PASAT. ConclusionsThe results suggest the CTIP can detect deficits in the speed at which people with MS process information. Thus, the CTIP offers an alternative means to the 3.0 second PASAT included in the Multiple Sclerosis Functional Composite for assessing such impairment.

Objective. To contrast the effect of a typical antipsychotic (haloperidol) and an atypical antipsychotic (olanzapine) on neurocognitive functioning in schizophrenia when learning and practice (LP) effects are controlled. Methods. Two groups of participants were recruited, 27 schizophrenia patients in their first 5 years of illness and 13 normal controls. Prior to double-blind randomisation, all subjects were assessed on four occasions within 5 days (prerandomisation period) on the same neurocognitive battery. Repeated assessment prior to randomisation was chosen as a method to control for LP effects. Patients were then randomised to 56 days of treatment with haloperidol or olanzapine (postrandomisation). All subjects were assessed on neurocognitive measures at Days 28 and 56. Results. LP effects were present during the prerandomisation period on motor tasks, verbal and visual short-term memory, attention, and on a measure of verbal working memory. There were no changes in performance for patients randomised to treatment with olanzapine or haloperidol or the normal control group during the postrandomisation period. Conclusions. Once LP effects are controlled, olanzapine and haloperidol do not affect performance on measures of motor functioning, verbal short-term memory, attention, verbal working memory, reaction time, visuospatial short-term memory, and visual working memory beyond that observed from LP effects.

In spite of the fact that reaction time (RT) measures are sensitive to the effects of traumatic brain injury (TBI), few RT procedures have been developed for use in standard clinical evaluations. The computerized test of information processing (CTIP) [Tombaugh, T. N., & Rees, L. (2000). Manual for the computerized tests of information processing (CTIP). Ottawa, Ont.: Carleton University] was designed to measure the degree to which TBI decreases the speed at which information is processed. The CTIP consists of three computerized programs that progressively increase the amount of information that is processed. Results of the current study demonstrated that RT increased as the difficulty of the CTIP tests increased (known as the complexity effect), and as severity of injury increased (from mild to severe TBI). The current study also demonstrated the importance of selecting a non-biased measure of variability. Overall, findings suggest that the CTIP is an easy to administer and sensitive measure of information processing speed.

The ability of a newly developed measure of information processing to detect deficits in cognitive functioning associated with multiple sclerosis (MS) was investigated. The Computerized Tests of Information Processing (CTIP; Tombaugh, T., & Rees, L. (1999). Computerized Tests of Information Processing (CTIP). Unpublished test. Ottawa, Ontario, Canada: Carleton University) was administered to 60 clinically definite MS patients and 60 healthy controls. MS patients responded significantly slower than controls on the reaction time tests composing the CTIP. Moreover, as the CTIP tests became more difficult (i.e. as processing demands increased), the difference between the performances of the two groups progressively increased. These results suggest the CTIP is sensitive to the cognitive deficits observed in MS and that this measure has the potential to serve as a viable alternative to traditional measures of information processing speed currently in use with MS patients.

The current study examined if a newly developed series of reaction time tests, the Computerized Tests of Information Processing (CTIP), were sensitive to simulation of attention deficits commonly caused by traumatic brain injury (TBI). The CTIP consists of three reaction time tests: Simple RT, Choice RT, and Semantic Search RT. These tests were administered to four groups: Control, Simulator, Mild TBI, and Severe TBI. Individuals attempting to simulate attention deficits produced longer reaction time scores, made more incorrect responses, and exhibited greater variability than cognitively-intact individuals and those with TBI. Sensitivity and specificity values were comparable or exceeded those obtained on the Test of Memory Malingering. As such, the CTIP offers considerable promise of serving as a viable malingering test that uses a distinctively different paradigm than the two-item, forced-choice procedure employed by traditional symptom validity tests.

Auditory and visual versions of the Adjusting-PSAT [Tombaugh, T. N. (1999). Administrative manual for the adjusting-paced serial addition test (Adjusting-PSAT). Ottawa, Ontario: Carleton University] were used to examine the effects of mild and severe traumatic brain injury (TBI) on information processing. The Adjusting-PSAT, a computerized modification of the original PASAT [Gronwall, D., & Sampson, H. (1974). The psychological effects of concussion. Auckland, New Zealand: Auckland University Press], systematically varied the inter-stimulus interval (ISI) by making the duration of the ISI contingent on the correctness of the response. This procedure permitted calculation of a temporal threshold measure that represented the fastest speed of digit presentation at which a person was able to process the information and provide the correct answer. Threshold values progressively declined as a function of the severity of TBI with visual thresholds significantly lower than auditory thresholds. The major importance of the current study is that the threshold measure offers a potentially more precise way of evaluating how TBI affects cognitive functioning than is achieved using the traditional PASAT and the number of correct responses. The Adjusting-PSAT offers the additional clinical advantages of eliminating the need to make a priori decisions about what ISI should be used in different clinical applications, and avoiding spuriously high levels of performance that occur when an “alternate answer” or chunking strategy is used. Unfortunately, the Adjusting-PSAT did not reduce the high level of frustration previously associated with the traditional PASAT.

The present study explored several different procedures for determining the amount of change that occurred on the Mini-Mental State Exam [MMSE; Folstein, M. F., Folstein, S. E., & McHugh, P. R. (1975). “Mini-Mental State”: A practical method for grading the cognitive state of patients for the clinician. Journal of Psychiatric Research, 12, 189–198] and Modified Mini-Mental State Exam [3MS; Teng, E. L., & Chui, H. C. (1987). The Modified Mini-Mental State (3MS) examination. Journal of Clinical Psychiatry, 48, 314–318] over short and extended test-retest intervals. The test-retest scores were drawn from a selected sample of elderly individuals who participated in the Canadian Study of Health and Aging [Canadian Study of Health and Aging. (1994). The Canadian study of health and aging: Study methods and prevalence of dementia. Canadian Medical Association Journal, 150, 899–913] and were tested on two occasions (CSHA-1 and CSHA-2) separated by 5 years. On each occasion the MMSE and 3MS were administered twice at approximately 3-month intervals. Thus, the mental status tests were administered four times: times 1 and 2 at CSHA-1 and times 3 and 4 at CSHA-2. Mean difference scores and percent of baseline scores showed relatively small group changes over both short and long test-retest intervals for the MMSE and the 3MS. A reliable change index based on a linear regression model controlled for practice effects, psychometric errors due to low reliability, regression to the mean, and accounted for the effects of various demographic variables. Consequently, this reliable change index provided a better estimate of the amount of change that occurred for individual participants than did the mean Retest-Test 1 difference, percent of baseline change, or a reliable change index based on a Retest-Test 1 difference score. Normative data for the change scores are provided.

The Paced Auditory Serial Addition Test (PASAT) was developed to assess the effects of traumatic brain injury (TBI) on cognitive functioning. Subsequent research has shown that the PASAT has clinical utility in detecting impairments in cognitive processing in patients with a wide variety of neuropsychological syndromes. Gronwall and Sampson (1974) originally assumed the PASAT measured speed of information processing. However, the PASAT is now recognized as a measure of multiple functional domains because it requires the successful completion of a variety of cognitive functions, primarily those related to attention. While the PASAT has demonstrated good psychometric properties such as high levels of internal consistency and test-retest reliability, several issues should be considered when administering and interpreting this test. For example, test-retest scores show that the PASAT is extremely susceptible to practice effects. The PASAT is also negatively affected by increasing age, decreasing IQ, and low math ability. Administration of the PASAT creates an undue amount of anxiety and frustration in participants which affects their performance on this and other neuropsychological tests, and may subsequently increase their reluctance to return for follow up testing. Demands for rapid responding place individuals with speech or language impairment at a distinct disadvantage, as it does for those who naturally speak slowly for cultural or geographic reasons. In conclusion, the PASAT represents a reliable test that has legitimate but restricted clinical applications. A low score on the PASAT may not necessarily indicate or confirm the presence of neurological pathology. The PASAT is a highly sensitive, non-specific test and as such, care must be taken to identify the reasons underlying any low score before interpreting it as clinically significant.

Normative data for the Trail Making Test (TMT) A and B are presented for 911 community-dwelling individuals aged 18–89 years. Performance on the TMT decreased with increasing age and lower levels of education. Based on these results, the norms were stratified for both age (11 groups) and education (2 levels). The current norms represent a more comprehensive set of norms than previously available and will increase the ability of neuropsychologists to determine more precisely the degree to which scores on the TMT reflect impaired performance for varying ages and education.

A modified computer version of the PASAT (Adjusting-PSAT; ) is described that measures speed of information processing and working memory by means of a temporal threshold rather than number of correct responses. This is accomplished by making the duration of the interval between numbers depend on the correctness of responding-a correct response decreases the interval between digits and an incorrect response increases the interval. Modality of presentation (visual and auditory) was factorially combined with problem difficulty (answers between 2-10 or 2-18). Performance of 60 healthy student volunteers on the Adjusting-PSAT was compared to that obtained on several traditional neuropsychological measures (Digit Span, Trail Making Test, and Symbol Digit Modality Test) and on a test of basic addition skills. The visual version of the test produced a lower threshold than did the auditory version, but problem difficulty did not produce a significant effect. Of the neuropsychological tests, Trails-B (TMT-B) was most highly correlated with thresholds. However, regression analyses revealed that math ability accounted for more variance than did TMT-B. The clinical implications of these finding are discussed.

The Test of Memory Malingering (TOMM) is described with particular emphasis directed towards the historical setting within which the TOMM was developed. This includes a review of the criteria for developing a memory malingering test, and the use of the empirically derived decision along with a discussion of the relative merits of empirically based vs. statistically based rules for detecting malingering. Data from a series of five experiments showing the sensitivity of the TOMM to feigned memory impairments, guidelines for interpretation of TOMM scores, and answers to frequently asked questions about the TOMM are provided. Finally, the ability of the TOMM to meet the Daubert guidelines is addressed.

Previous research has examined age effects in rates of forgetting at short delay intervals of 20-30 min. The present study examined age effects in three verbal memory tasks at longer delay intervals of up to 62 days. Study participants consisted of 371 community-dwelling men and women comprising three age groups 20-39, 40-59, and 60-79 years. Age differences in acquisition and 20-min delayed recall were found on each of the memory tasks (paragraph, word list, and word pairs). However, all age groups showed equivalent rates of forgetting after this short delay interval. When participants were required to retain information for longer delay intervals (i.e., 1-62 days), increasing age was associated with faster rates of forgetting for day 1, but not over longer delay intervals. Age differences in rates of forgetting for longer delay intervals and the facilitating effects of prompted recall are discussed in terms of encoding and storage versus retrieval processes.

Research on the Test of Memory Malingering (TOMM) [Tombaugh, T. N., 1996. The Test of Memory Malingering. Toronto, Canada: Multi-Health Systems], has consistently shown that it is sensitive to exaggerated or deliberate faking of memory impairment, but it is relatively unaffected by a wide variety of neurological impairments causing genuine memory dysfunction. However, there is little research on the effects that affective disorders have on the TOMM. The current study examined how inpatients diagnosed with major depression performed on the TOMM. Results show that the TOMM is unaffected by affective state. These results, combined with those from previous research, provide converging evidence that performance on the TOMM below a cutoff score of 45 cannot be attributable to depression, neurological impairment, age or education.