Sternberg Memory Scanning Test Research Articles

Next-Day Effects of Ramelteon (8 mg), Zopiclone (7.5 mg), and Placebo on Highway Driving Performance, Memory Functioning, Psychomotor Performance, and Mood in Healthy Adult Subjects

To evaluate the next-morning residual effects of ramelteon (8 mg), zopiclone (7.5 mg), and placebo on driving performance, memory functioning, psychomotor performance, and mood in healthy adult subjects following bedtime dosing and a middle of the night awakening. Single-center, randomized, double-blind, double-dummy, placebo-controlled, crossover study. Utrecht University, The Netherlands. 30 healthy volunteers (15 males and 15 females). a single dose of ramelteon (8 mg), zopiclone (7.5 mg), and placebo, administered at bedtime. A balance test was performed at night. Other tests were performed the following morning, 8.5 h after administration. Subjects performed a 100-km highway driving test in normal traffic. Primary outcome measure was the standard deviation of the lateral position (SDLP), i.e., the weaving of the car. After driving, cognitive, memory, and psychomotor tests were performed and mood was assessed. SDLP was significantly increased after the intake of ramelteon (+2.2 cm) and zopiclone (+2.9 cm). Ramelteon and zopiclone produced significant impairment on reaction time (P<0.024) in the Sternberg Memory Scanning Test, slow (P<0.007) and fast (P<0.010) tracking, reaction speed (P<0.015) and tracking (P<0.001) in the Divided Attention Test, and delayed recall (P<0.032) in the Word Learning Test. In contrast to ramelteon, zopiclone additionally impaired performance on the Digit Symbol Substitution Test (P<0.001) and the balance test (P<0.001). Ramelteon (8 mg) and zopiclone (7.5 mg) significantly impaired driving performance, cognitive, memory, and psychomotor performance the morning following bedtime administration. In contrast to zopiclone, ramelteon produced no balance impairments. CLINICAL TRIAL IDENTIFIER: NCT00319215 (www.clinicaltrials.gov).

Predicting psychopharmacological drug effects on actual driving performance (SDLP) from psychometric tests measuring driving-related skills

RationaleThere are various methods to examine driving ability. Comparisons between these methods and their relationship with actual on-road driving is often not determined.ObjectiveThe objective of this study was to determine whether laboratory tests measuring driving-related skills could adequately predict on-the-road driving performance during normal traffic.MethodsNinety-six healthy volunteers performed a standardized on-the-road driving test. Subjects were instructed to drive with a constant speed and steady lateral position within the right traffic lane. Standard deviation of lateral position (SDLP), i.e., the weaving of the car, was determined. The subjects also performed a psychometric test battery including the DSST, Sternberg memory scanning test, a tracking test, and a divided attention test. Difference scores from placebo for parameters of the psychometric tests and SDLP were computed and correlated with each other. A stepwise linear regression analysis determined the predictive validity of the laboratory test battery to SDLP.ResultsStepwise regression analyses revealed that the combination of five parameters, hard tracking, tracking and reaction time of the divided attention test, and reaction time and percentage of errors of the Sternberg memory scanning test, together had a predictive validity of 33.4%.ConclusionThe psychometric tests in this test battery showed insufficient predictive validity to replace the on-the-road driving test during normal traffic.

Examining the Link between Information Processing Speed and Executive Functioning in Multiple Sclerosis

Slowed information processing speed (IPS) is frequently reported in those with multiple sclerosis (MS), and at least 20% are compromised on some aspect of executive functioning also. However, any relationship between these two processes has not been examined. The Sternberg Memory Scanning Test, Processing Speed Index (WAIS-III), Delis Kaplan Executive Function System (D.KEFS), and Working Memory Index (WMS-III) were administered to 90 participants with MS. Their performance on the PSI was significantly below the normative scores but no deficits in memory scanning speed were evident. The initial response speed of the Sternberg and the PSI were more closely related to D.KEFS performance, particularly in timed tasks with a high cognitive demand (switching tasks). In contrast, memory scanning speed was related to working memory. This study reinforces the link between IPS and working memory in MS, and supports the suggestion that IPS is not a unitary construct.

PRACTICAL METHODS FOR THE CLINICAL ASSESSMENT OF INFORMATION PROCESSING SPEED

The rate at which individuals are capable of processing information is considered a sensitive indicator of brain dysfunction, particularly among clinical populations whose neurocognitive impairments generally are considered relatively mild in nature. Assessment of information processing speed often is confounded, however, by comorbid impairments in other constructs of neurocognition, including attentional capacity, visuospatial perception, language, immediate memory, and motor speed/coordination. This investigation examined the effect of controlling for various potential confounders on the strength of associations among several potential measures of information processing speed. Participants were 64 patients diagnosed with clinically definite multiple sclerosis. Analysis indicated consistent significant and positive associations among measures of processing speed, which generally persisted despite simultaneous statistical control of potential confounding factors. Results imply that examined confounding variables are similarly related to the measures of processing speed. Therefore, any of the measures of information processing speed considered in this study may be used as a proxy for the more direct measure of this construct derived from the Sternberg Memory Scanning Test.

Relationship between information processing speed in temporal lobe epilepsy and white matter volume

Abnormalities in white matter have been linked to processing speed impairment in clinical populations (e.g., multiple sclerosis, closed head injury). Recent studies indicate the presence of significant reduction in cerebral white matter volume in some patients with chronic temporal lobe epilepsy (TLE). The objective of this study was to examine the relationship between white matter volume and processing speed and performance efficiency on the Sternberg Memory Scanning Test (SMST). The study groups included TLE subjects with white matter volume reduction ( n = 13), TLE subjects with normal white matter volume ( n = 14), and healthy controls ( n = 18). The groups did not differ in total cerebral gray matter volume. Compared with the controls, the reduced white matter volume TLE group exhibited a significantly steeper slope on the SMST. This was characterized by a disproportionate increase in reaction time with increased processing demands (set size), particularly for negative probe trials. In contrast, no significant differences on the SMST were evident between controls and the normal white matter volume TLE group. These findings suggest the presence of information processing speed and efficiency impairment in TLE and its relationship with white matter volume integrity.

Acute and subchronic effects of levocetirizine and diphenhydramine on memory functioning, psychomotor performance, and mood

Background: Central nervous system adverse effects, such as sedation, often accompany the use of first-generation antihistamines. These effects might interfere with memory functioning and psychomotor performance. Levocetirizine was recently introduced as a new antihistamine said to be free from sedative effects. Objective: We sought to investigate the effects of levocetirizine (5 mg), diphenhydramine (50 mg), and placebo on memory and psychomotor performance after acute (day 1) and subchronic (day 4) daily administration in 48 healthy volunteers (24 men and 24 women). Methods: This study was a double-blind, placebo-controlled, randomized clinical trial. Treatments were administrated on days 1, 2, 3, and 4, 3 hours before the start of the laboratory test battery (performed on days 1 and 4), comprising a word-learning test, the Sternberg Memory Scanning Test, a tracking test (easy and hard version), and a divided attention test (tracking and memory scanning simultaneously). Statistical analyses were performed separately for days 1 and 4 by using analysis of variance. Results: On day 1, diphenhydramine significantly impaired tracking performance (easy: F1,90 = 25.9, P < .0001; hard: F1,90 = 20.5, P < .0001) and divided attention (tracking: F1,90 = 23.8, P < .0001; memory scanning: F1,90 = 22.0, P < .0001). Results on word-learning tests and Sternberg Memory Scanning Tests were not significantly impaired. On day 4, the effects of diphenhydramine did not reach significance. In contrast, on both days 1 and 4, levocetirizine did not significantly impair laboratory test performance. Conclusion: The results show that memory, attention, and tracking performance are unaffected after acute and subchronic administration of levocetirizine (5 mg), whereas diphenhydramine (50 mg) significantly affected divided attention and tracking after acute administration. (J Allergy Clin Immunol 2003;111:623-7.)

Effects of Alprazolam on Driving Ability, Memory Functioning and Psychomotor Performance: A Randomized, Placebo-controlled Study

Alprazolam is prescribed for the treatment of anxiety and panic disorder. Most users are presumably involved in daily activities such as driving. However, the effects of alprazolam on driving ability have never been investigated. This study was conducted to determine the effects of alprazolam (1 mg) on driving ability, memory and psychomotor performance. Twenty healthy volunteers participated in a randomized, double-blind, placebo-controlled crossover study. One hour after oral administration, subjects performed a standardized driving test on a primary highway during normal traffic. They were instructed to drive with a constant speed (90 km/h) while maintaining a steady lateral position within the right traffic lane. Primary performance measures were the Standard Deviation of Lateral Position (SDLP) and the Standard Deviation of Speed (SDS). After the driving test, subjective driving quality, mental effort, and mental activation during driving were assessed. A laboratory test battery was performed 2.5 h after treatment administration, comprising the Sternberg Memory Scanning Test, a Continuous Tracking Test, and a Divided Attention Test. Relative to placebo, alprazolam caused serious driving impairment, as expressed by a significantly increased SDLP (F1,19 = 97.3, p < .0001) and SDS (F1,19 = 30.4, p < .0001). This was confirmed by subjective assessments showing significantly impaired driving quality (F1,19 = 16.4, p < .001), decreased alertness (F1,19 = 43.4, p < .0001), decreased mental activation (F1,19 = 5.7, p < .03) and increased mental effort during driving (F1,19 = 26.4, p < .0001). Furthermore, alprazolam significantly impaired performance on the laboratory tests. In conclusion, alprazolam users must be warned not to drive an automobile or operate potentially dangerous machinery.

Changes of attention and memory in a group of patients with multiple sclerosis

Cognitive impairment was observed in patients with multiple sclerosis (MS), not only in the later phase of the disease, but also early in the disease [1 /3]. There is no evidence that its occurrence has been a consequence of depression, mood changes, or fatigue after physical exercise. Furthermore, a certain degree of cognitive impairment may occur without any major physical disability symptoms in these patients [4]. The most frequently observed disturbances of cognitive functions in patients with MS were those of shortterm memory and sustaining of attention, followed by conceptual thinking problems and verbal fluency disorder [5]. The nature of attention-related problems in MS has not been definitely explained by previous investigations [5 /9]. Several methods were used to assess different aspects of attention in those patients (paced auditory serial addition test (PASAT), the Stroop test, Sternberg memory scanning test, vigilance tasks auditory As and auditory trails A tests). Working memory, which is a part of short-term memory processes, is closely associated with visual and auditory attention systems [10]. Disturbances of explicit memory in patients in the early and middle phases of MS were observed both on verbal and non-verbal tasks [11]. According to Litvan et al. [12] the short-term memory performance in patients with MS is generally intact, except for the retrieval of data, measured through digit-retention capacity. On the other hand, deficit of digit retention capacity has been reported to exist in patients with less than 2 years’ duration of illness [13]. Few studies on implicit memory [14,15] suggested that patients with MS would perform normally on a motor skill task and priming. The aim of this investigation was to assess the cognitive performance of patients with MS on attentionand memory-related tasks. The contributions of patients’ clinical and demographic characteristics to their cognitive performance were also analyzed in the present study.

The effect of Ginkgo biloba on memory in healthy male volunteers

The purpose of this study was to investigate possible effects of Ginkgo biloba, a widely used herbal extract, on memory. This study incorporated a double-blind, placebo-controlled design, which used 30 healthy male subjects in each of two groups. The treatment group received two 60-mg tablets of BioGinkgo (LI 1370) daily for 5 days, while the placebo group received a placebo. On the fifth day, after a 2-h waiting period, all subjects were given the Sternberg Memory Scanning Test [Q. J. Exp. Psychol. 27 (1975) 1.], a reaction time control test, the vocabulary and digit span subtests of the WAIS-R [Wechsler D. Manual for the Wechsler adult intelligence scale — revised. New York: Psychological Corporation, 1981.], a reading span test [J. Verbal Learn. Verbal Behav. 19 (1980) 450.] and a prose recall test [Discourse Proc. 13 (1990) 387.]. Blood pressure, heart rate and side effects were also monitored throughout the study. Nonsignificant results were found on all interactions involving treatment group on all tests except the Sternberg Memory Scanning Test. The extract appeared to be safe but largely ineffective in enhancing memory.

Information processing speed in patients with multiple sclerosis.

We have recently proposed that the cognitive deficits of patients with multiple sclerosis (MS) share numerous characteristics associated with the syndrome of subcortical dementia. One such characteristic, slowness of mental processing, was evaluated in the present study. Thirty-six MS patients were compared to 26 normal controls of equivalent age, education, and verbal intelligence on the Sternberg memory scanning test. As anticipated, the motor-involved MS patients had an overall slower reaction time than did controls. Their scanning rate, a measure of pure cognitive speed, was also significantly slower than controls. These results suggest that MS patients exhibit a slowing of mental processing independent of motor involvement.

A preliminary investigation of “albert 285” (HWA 285) on psychomotor performance, mood, and memory

AbstractEight healthy female volunteers received 150, 300, and 450 mg of HWA 285 and placebo according to a randomized, double‐blind crossover design. The subjects completed a battery of psychological tests including critical flicker fusion (CFF), choice reaction time (CRT), subjective ratings of drug effects (LARS), and a Sternberg memory scanning test (SMST) 1 and 2 hr following treatment. No statistically significant changes from placebo were observed on CFF, CRT, or subjective ratings of drug effects. However, memory as assessed using the Sternberg technique was significantly improved with respect to placebo 1 hr following treatment with HWA 285 at 150, 300, and 450 mg dose levels. The action of the drug was found to be specific in its effects on the central serial comparison stage of the information processing model.