Interaction Effects of Synonymity, Intralist Synonym Cohesiveness, and List Length in Multi-Trial Free Recall

1976 ◽  
Vol 38 (2) ◽  
pp. 507-521
Author(s):  
Rudolf R. Abramczyk ◽  
W. Douglas Thompson ◽  
Donald E. Jordan ◽  
Robert A. Weeks
Keyword(s):  
Free Recall ◽  
Semantic Similarity ◽  
List Length ◽  
Differential Effect ◽  
Interaction Effects ◽  
Impaired Performance ◽  
Negative Results ◽  
Intralist Similarity ◽  
Retrieval Strategies ◽  
High Degree

In each of three experiments, different lists of synonymous and minimally related adjectives were presented to groups of subjects for multi-trial free recall. The results in Exp. 1 supported the hypothesized interaction of synonymity and list length on recall and organization, predicting impaired performance on long lists of synonyms. Two partial replications (Exps. 2 and 3) obtained negative results. In Exp. 4 five measures of semantic cohesiveness were employed to verify the presence of a high degree of semantic similarity in the three experimental lists of synonymous adjectives. It was concluded that list synonymity has a differential effect primarily on the retrieval strategies employed and that subjects are still able to achieve optimal recall and organization with lists of high intralist similarity.

scholarly journals Effects of semantic relations, repetition of words, and list length in word list recall of Alzheimer's patients

2008 ◽  
Vol 66 (2b) ◽  
pp. 312-317 ◽  
Author(s):  
Orlando F.A. Bueno ◽  
Paulo H.F. Bertolucci ◽  
Maria Gabriela M. Oliveira ◽  
Jacqueline Abrisqueta-Gomez
Keyword(s):  
Free Recall ◽  
List Length ◽  
Word List ◽  
Semantic Relations ◽  
Healthy Elderly ◽  
Facilitating Factors ◽  
Word Lists

INTRODUCTION: Semantic relations among words and repetition enhance free recall, but it is unknown if these facilitating factors are effective in dementia. METHOD: Alzheimer's patients (MILD-Alz, MOD-Alz) were compared to healthy elderly. Fifteen-word lists were read out to the subjects. In four sets of lists the words in intermediary input positions were semantically related or not, or the midlist words were repeated, or they were repeated and semantically related. RESULTS: The usual third peak of recall of semantically related words was not observed in MOD-Alz, repetition of words did not increase recall of the patients, and the combination of relatedness and repetition benefited only MID-Alz. In a second experiment, with related or unrelated midlist words, and list length shortened from 15 to 9 words, semantic facilitation was observed in mild and moderate Alzheimer´s patients, although diminished compared to controls. CONCLUSION: Progression of dementia turns facilitating factors of recall less effective.

DETECTION OF AUTOANTIBODIES AND ALLOANTIBODIES AGAINST PLATELET-ASSOCIATED ANIGENS

1987 ◽  
Author(s):  
R McMillan ◽  
P Tani ◽  
P Berchtold ◽  
F Millard
Keyword(s):  
Hla Antigens ◽  
Class I ◽  
High Dose ◽  
Hla Antibodies ◽  
Negative Results ◽  
Single Donor ◽  
Prognostic Group ◽  
Successful Outcomes ◽  
Well Assay ◽  
High Degree

Although autoantibodies against the platelet glycoproteins (GP) and a 1loantibodies toward class I HLA antigens have been demonstrated using various methods, practical techniques for their detection have not been available.We studied 59 patients with chronic immune thrombocytopenic purpura (ITP) where platelet-associated and plasma autoantibodies against the GP Ilb/IIIa complex and GP lb were measured using a newly developed imraunobead assay and a previously described microtiter well assay. The specificity of both assays depends on the monoclonal antibody employed (e.g., GPIIb/IIIa, lb or HLA). Platelet-associated autoantibody was detected using the immunobead assay in 21 of 28 patients (13 with anti-GPIIb/IIIa and 8 with anti-GPIb). Plasma autoantibodies were noted in 34 of 59 patients (21 with anti-GPIIb/IIIa, 11 with anti-GPIb and 2 with both). Positive results were noted in 30 of 59 ITP patients using the immunobead assay and in only 14 of 59 using the microtiter well assay, suggesting that solubilization prior to antibody addition, as in the microtiter well assay, alters epitope stability. However, the microtiter well assay appears to define a poor prognostic group. Of 11 patients with positive well assays who underwent splenectomy, only one achieved a complete remission, 3 have died and all require continuous high-dose steroids or immunosuppressants. Of the 31 thrombocytopenic controls studied, all gave negative results using both assays.The immunobead assay was adapted to specifically measure anti-HLA antibodies and was used to evaluate 51 single donor platelet transfusions given to 7 patients refractory to random platelets. Twenty-nine of 33 (88%) transfusions associated with a negative assay had successful outcomes (1 hr increment >7500) while only 2 of 18 (11.1%) episodes associated with a positive test had successful outcomes. Only 1 unsuccessful transfusion episode was associated with a negative immunobead and a positive antiglobulin test suggesting that transfusion-related alloantibodies, other than to class I HLA antigens, are an uncommon cause of refractoriness.We conclude that these two clinically adaptable assays are capable of measuring both autoantibodies and anti-HLA alloantibodies with a high degree of sensitivity.

Verbal fluency in Parkinson's disease: results of a 2-min fluency test

2006 ◽  
Vol 18 (1) ◽  
pp. 38-41 ◽  
Author(s):  
B. Scholtissen ◽  
J. Dijkstra ◽  
J. Reithler ◽  
A. F. G. Leentjens
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Executive Functioning ◽  
Verbal Fluency ◽  
Healthy Controls ◽  
Impaired Performance ◽  
Phonemic Fluency ◽  
Retrieval Strategies ◽  
Fluency Task ◽  
Fluency Test

Background:Patients suffering from Parkinson's disease (PD) are often reported to have an impaired performance on tests measuring executive functioning, such as fluency tasks.Aim:To investigate whether verbal fluency is impaired in PD patients (n = 25) compared with healthy controls (n = 15) using a 2-min semantic and phonemic verbal fluency test. A 2-min version of the fluency task was used to allow for more switches between clusters to study retrieval strategies more adequately.Results:No differences in performance on both semantic and phonemic fluency tasks between the PD patients and the control persons were found. Moreover, both groups appeared to use the same retrieval strategies.Conclusion:Patients suffering from PD appear to use the same strategies for producing words as healthy controls do. Different pathways may be involved in switching clusters during the fluency task than in other types of switching that may be impaired in PD, such as motor switching and concept-shifting.

scholarly journals IMMUNOLOGICAL AND CHEMICAL INVESTIGATIONS OF VACCINE VIRUS

1936 ◽  
Vol 64 (3) ◽  
pp. 439-452 ◽  
Author(s):  
Robert F. Parker ◽  
Thomas M. Rivers
Keyword(s):  
Coefficient Of Variation ◽  
Vaccine Virus ◽  
Agglutination Reaction ◽  
Test Antigen ◽  
End Point ◽  
Negative Results ◽  
The Mean ◽  
Different Strains ◽  
High Degree ◽  
Infectious Unit

Methods have been described by which the number of elementary bodies present in a suspension can be estimated. It has been shown that by means of replicate counts, in which the Petroff-Hausser chamber was used, a high degree of accuracy can be attained. By means of the Gates densitometer, the number of elementary bodies in a suspension can be determined with a coefficient of variation of about 3.0 per cent. A method has been described by which the accuracy of estimation of the infectious titer of a suspension can be increased without greatly enlarging the number of animals employed. This consists of selecting as the end-point that dilution of virus which on intradermal inoculation in a rabbit would lead theoretically to an equal number of positive and negative results. The statistical advantages of this method have been confirmed by the experiences of other laboratories. By the application of the methods described, there was shown to be a direct correlation between the number of elementary bodies and the number of infectious units of virus present in a given suspension. At the mean of the distribution this ratio is as the logarithms 9.62 to 8.0. To extrapolate this curve, in order to determine the number of elementary bodies present in a single infectious unit, while tempting, is probably not justifiable. It must likewise be remembered that the data given apply to a particular strain of vaccine virus, and that the number of infectious units has been determined by intradermal inoculation of rabbits. It appears also that this method may be of value in studies of the virulence of different strains of vaccine virus, since by its application one may determine not only the infectious liter of a suspension, but its content of elementary bodies. In the agglutination reaction it was found that optimum titers of serum were obtained when the test antigen contained from 2.0 x 109 to 1.05 x 1010 elementary bodies per cc. Approximately 1.95 x 108 particles per cc. of suspension were required for the production of visible agglutination.

The Effects of Intravenous Diazepam and Hyoscine upon Human Memory

1984 ◽  
Vol 36 (1) ◽  
pp. 133-144 ◽  
Author(s):  
C. D. Frith ◽  
J. T. E. Richardson ◽  
M. Samuel ◽  
T. J. Crow ◽  
P. J. McKenna
Keyword(s):  
Semantic Similarity ◽  
Human Memory ◽  
Item Recall ◽  
Double Blind ◽  
Immediate Serial Recall ◽  
Impaired Performance ◽  
Intravenous Diazepam ◽  
Abstract Words ◽  
Acquisition Processes ◽  
Phonemic Similarity

Diazepam and hyoscine are known to have amnesic effects when administered intravenously. The two drugs are pharmacologically quite different from each other and might be expected to produce qualitatively distinct patterns of impairment in formal memory tasks. Groups of normal volunteers received intravenous administrations of diazepam, hyoscine and saline following a double-blind procedure and were then tested on immediate serial recall. Diazepam and hyoscine produced similar deficits on concrete and abstract words whether scored for ordered recall or item recall. In terms of ordered recall, phonemic similarity produced impaired performance under all three administrations, but semantic similarity did not. In terms of item recall, diazepam and hyoscine produced impaired performance on unrelated words, but the impairment was reduced under conditions of either phonemic or semantic similarity. There were also some interesting differences between diazepam and hyoscine in terms of their effects upon the shape of the serial-position curve and upon the types of intrusion error. The results confirm that both diazepam and hyoscine impair acquisition processes but fail to distinguish the effects of the two drugs upon different categories of encoding operations.

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