Digitized Theses and Dissertations

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A revision of the New Adult Reading Test
(1988) Blair, Jennifer R.; Spreen, Otfried
A comparison of current with premorbid intellectual level is integral to the assessment of organic deterioration. Premorbid test data are rarely available, however, so methods of estimation are needed. Several methods measure performance on tests which are believed to resist deterioration. Other methods utilize the correlation between demographic variables and actual IQ in unimpaired subjects to estimate premorbid IQ. The limitations of these methods are discussed. The New Adult Reading Test (NART) was developed as another attempt to assess premorbid IQ. Nelson and O'Connell (1978) noted that demented patients' word reading ability was maintained in spite of intellectual deterioration. Since word reading correlated highly with IQ level in a group of unimpaired subjects, it was considered a possible indicator of premorbid intelligence levels. The maintenance of word reading ability is most likely due to previous familiarity with the words, rather than the ability to phonetically decode those words. Difficult words which can only be deciphered through the application of phonetic rules may be correctly read by the unimpaired, but prove too complex for a demented population. In order to capitalize on the individual's familiarity with words, the NART was devised. The NART consists of 50 words which could not be correctly phonetically decoded. In order to pronounce the words correctly, the individual must have previously learned how they sound. Nelson and O'Connell (1978) found that the NART correlated significantly with IQ in an unimpaired population, and discrepancies between predicted (on the basis of NART performance) and actual IQs were significantly greater in a demented population. While the NART has promise as an assessment tool for the determination of premorbid intellectual function, it must be modified for current use in a North American population. The purpose of this study was to develop a revised NART word list and to standardize it on an unimpaired Canadian/U.S. population. Sixty-six unimpaired subjects were tested with a revised NART and all subtests of the WAIS- R. Demographic variables were also recorded in order to compare prediction accuracies between revised NART and demographic variable prediction equations. It was hypothesized that the revised NART score would correlate significantly with FSIQ, VIQ and PIQ. It was also hypothesized that prediction would prove more accurate with the use of equations based on revised NART and demographic variables than with demographic variables alone as outlined by Barona, Reynolds and Chastain (1984). All hypotheses were supported. Correlations between actual VIQ, PIQ and FSIQ, and predicted IQs on the basis of revised NART score were. 83, .40, and .75, respectively, all significant at p<.001. Stepwise multiple regressions of VIQ, PIQ and FSIQ on age, sex, education, occupation, source (U.S. vs. Canadian) and NART score were calculated to generate prediction equations for the estimation of IQs. NART score was the only variable entered into all three prediction equations. Prediction was more accurate with equations based on revised NART score than with prediction equations developed by Barona, et al. (1984). The present study provides strong support for the use of the revised NART as an assessment tool for the determination of organic deterioration. The support of further validation research is needed, however, before it can be used with confidence in a clinical setting.
Cross-cultural comparison of implicit beliefs and self-referent beliefs about aging and memory performance
(1999) Aulakh, Harpreet Kaur; Hultsch, David F.
This study investigated the relationship between beliefs about memory and memory performance within a cross-cultural context. Self-referent and implicit beliefs were measured with the Personal Beliefs about Memory Questionnaire (PBMI) and the General Beliefs about Memory Questionnaire (GBMI), respectively (Lineweaver & Hertzog, in press). Memory performance was measured with the Brief Visuospatial Memory Test - Revised (BVMT) (Benton, 1990). Participants were 60 South Indian males recruited from India (30 younger adults and 30 older adults) and 60 Canadian males (30 younger adults and 30 older adults). Results indicated that the Indian participants generally held more positive self-referent beliefs and they believed that memory for other adults is better further into later life than the Canadians participants. Intelligence, as measured by the Culture Fair Intelligence Test, (CFIT; Cattell & Cattell, 1960) was found to be significantly better for the Canadians, thus, it was used as a covariate measure in the memory performance analysis. The results from the memory performance analysis did not show any significant differences between the Indians and Canadians. Thus, even though beliefs were significantly more positive for the Indian participants, memory performance did not differ between these groups.
Inferential paths in social perception
(1978) Norman, Stephen A.; Hoppe, Ronald A.
The presenter esearch explored the use of inferential paths in social perception. An inferential path is a series or chain of inferences that a person makes when assessing the meaning of social behaviour. A review of literature suggested that the effects of inferential paths are primarily psycholinguistic in nature. Two particular inferential paths were identified and examined experimentally in two pilot studies. In these studies subjects were shown behaviour and guided through different inferential paths. It was found that the conclusions drawn by subjects about the behaviour they saw depended on the inferential path through which they were guided. In the second of these studies, evidence was obtained to suggest that subjects who we re not specifically guided through the inferential paths, probably use them anyway. A final experiment looked at the possibility that role requirements dictate the inferential path taken by those who are specifically guided through a path. Role requirements describe the needs people have when they occupy particular roles in a social situation. Previous research demonstrated that role requirements, like inferential paths, are related to person perception. In general, when subjects interact with another person, or anticipate such interaction, they state that they know that person's traits, dispositions or personality, better than subjects who do not have to interact. In other words, part of the role requirements of people who interact with others is the perception of knowing those with whom they interact. Trait attributions satisfy these requirements. They provide knowledge of the other person. The final experiment indicated that in part, this knowledge is inferred via inferential paths. Results were discussed with respect to various possible models of person perception. The model closest to the data holds that role requirements activate cognitive processes which in turn determine person perception.
Ion transport mechanisms of bola-amphiphiles in planar bilayer membranes
(1997) Loock, Daniela; Fyles, Thomas M.
The bilayer clamp technique was used as an investigative tool to explore the ion transport activity of bola-amphiphiles across planar lipid bilayers. It was demonstrated that 'small' synthetic molecules can transport ions across lipid bilayer membranes with mechanisms that have not been reported for natural protection channels. In addition to the step conductance changes that are typical for natural ion transporters a variety of signal shapes were observed. The overall transport behaviour could be controlled by influencing specific steps in the mechanism via small structural alterations of the bola-amphiphiles. This approach was analogous to the introduction of point mutations in proteins. Transporter aggregates were assumed as the ion conducting structure of most bola-amphiphiles investigated. It has been demonstrated that controlling the forces that lead to the stabilization and destabilization of aggregates will lead to control of the observed transport mechanism which was reflected in the signal shapes observed. Head group repulsion, the hydrophilic/hydrophobic balance in the wall units, and the flexibility of the molecule offer possibilities for the regulation of ion transport. Charge selectivity could be controlled via the introduction of charged head groups and via the degree of hydration of the wall units. 'Dryer' pores led to perfect cation:anion selectivity which in turn gave rise to an unusual signal shape. The development of a local Donnan-potential was invoked in the transport mechanism of these bola-amphiphiles. Rectifying current-voltage responses were achieved by the introduction cl asymmetry into the mechanism. Two different classes of transporters displayed voltagegated behaviour in planar bilayer membranes. In one case the asymmetry was introduced into the structure of the bola-amphiphile itself. In a second case the unequal distribution of symmetric transporter molecules in the two bilayer leaflets led to the observed non-ohmic current-voltage relationship. The activity of eleven transporter molecules was studied in planar lipid bilayers and was compared to results previously obtained for these compounds in vesicles. In some cases different conclusions were reached from the two experiments.
A fragment of Korean phrase structure grammar
(1988) Kim, Yong-Bum; Hukari, Thomas E.
This dissertation attempts to provide a phrase structural account of the Korean language within a restricted syntactic framework which dispenses with multi-stratal representations of sentences. It is shown that the major portions of the Korean syntax can be accounted for by a slight extension of the currently prevailing theory of Generalized Phrase Structure Grammar. The findings obtained in this thesis are two-pronged. One is related to the way in which some Korean language facts are analyzed: this aspect of our results led us to conclude that an adequately restricted descriptive model serves as a heuristic in the analysis of languages. The other involves the formal aspect of the theory which necessitated a slight relaxation of restrictions imposed on the grammar. It is shown in Chapter 2 that what is traditionally known as a subject marker in Korean is also a focus marker in the sense that it encodes exclusiveness of given information; it is also claimed that two types of multiple nominative constructions are identifiable. Chapter 3 is devoted to justifying the existence of two separate structures of similar appearance: the missing object construction and the stative sentential subject construction. Chapter 4 analyzes the Korean honorific system, especially the subject honorific system as a control-agreement phenomenon. Chapter 5 provides an unified account of two linguistic phenomena known as scrambling and topicalization. Focusing is included in our account m addition to topicalization and scrambling. These three phenomena are captured by a single generation mechanism, while differences in subjacency and the use of resumptive pronouns are explained through parochial statements. If the framework employed here is claimed to be a universal linguistic model, some of the restrictions imposed on the theory should be relaxed. Based on the analysis of Korean, the following changes are suggested: metarules should be able to apply to their own output and in non-Lexical environments; extraction from fillers should be allowed: the unbounded dependency feature (or SLASH) should be able to take a set of categories as its value. We believe that implementation of these suggestions into the grammar will increase the generative capacity of our model beyond that of the context-free grammar.
Bioluminescence and color change in Euphausia pacifica
(1979) Harvey, Brian J.; Mackie, G. O.
Some of the morphological, physiological and biochemical characteristics of the photophores of the euphausiid shrimp Euphausia pacifica are examined. Electron micrographs of the light organ show that the 'rod mass', or light-emitting zone, is composed of a highly ordered crystalline substance in intimate contact with elements of the circulatory system, and that a sphincter system exists at the edge of this body, so situated as to control the irrigation of the area. The innervation of these sphincters is described, as are the dioptric, or light-directing, structures. The phenomenon of Flash-Stimulated Inhibition (extinction of a luminescent display by strong light) is investigated in pinioned specimens stimulated to luminesce by the injection of 40 pg 5-HT. Records from whole animals and from ocular photophores alone are presented. Progressive isolation of the luminescing organ suggests that it may respond to light without the intervention of the central nervous system; studies with luminescing homogenates demonstrate that Flash Stimulated Inhibition can occur in vitro, and it is concluded that the phenomenon is not behaviourally significant. Several characteristics of the luminescence system in vitro are investigated, including pH dependence and temperature optimum. A new cofactor, blood-borne and probably protein, is found to be essential to the light reaction. The color change mechanism of E. pacifica is investigated. Red chromatophores of the integument, abdominal nerve cord and photophores are described, and their response to ambient light and to 5-HT is detailed. The behavioural implications of these findings are discussed.
Studies on terpenoids from Saussurea lappa Clarke
(1970) Banks, Calvin Mitchell; Jain, Tikam C.
This dissertation consists of two parts, part one deals with the N-bromosuccinimide-induced carbocyclization of germacranolides and some interesting aspects of their chemistry. Part two is concerned with the structure elucidation of an erroneously reported diterpene alcohol which was identified as 22-dihydrostigmasterol. Treatment of costunolide l and dihydrocostunolide 2 with NBS in aqueous acetone at room temperature furnished bromolactones 3, 4 and 5 and 6, 7, and 8 respectively. Structural evidence for these bromolactones rests upon spectral data and chemical correlations with santanolide 'c' 9 and related lactones. Unlike previous brominative cyclization studies, our substrates gave a variety of products in quantitative yields. This was attributed to the conformational control the y-lactone ring exercises over the germacrane skeleton. Also demonstrated was the reversible nature of the thermally induced valence isomerization of amine adduct 10 to dehydrosaussurea lactone amine adduct 11. Mild base treatment of the methiodide salt of adduct 11 yielded dehydrosaussurea lactone 12 which was needed for further NBS cyclization studies. Guided by the TT-TT interactions (Amax 211.5 nm) of substrate 12 a carbocyclization was predicted. Treatment of dehydrosaussurea lactone 12 with NBS in aqueous acetone at room temperature afforded bicyclic lactones 3, 4 and 5 which provided the first example of cyclization of a lactone based on the elemane framework. Thus a new dimension is added to the biosynthetic hypothesis of bicyclic sesquiterpenes, namely the intermediacy of elemanoids besides germacranolides in the biogenetic pathway of bicyclic sesquiterpenes. During this study it was found that dimethylamine cleaves y-lactone rings fused to six-membered systems yielding amides, whereas this does not occur with ten-membered rings. Also examined was a comparison of the elimination procedures for the regeneration of heat sensitive a, B-unsaturated y-lactones from their parent amine adducts. It was established that the mild base treatment was superior to the Hofmann method. Finally, the structure of vachanic acid is described.
The design of pion and muon channels
(1972) Al-Qazzaz, Nadhim; Pearce, R. M.
Various concepts for the transportation of pions and muons from production targets external to the TRIUMF accelerator have been studied. A dual purpose magnetic channel capable of providing a pion beam and a muon beam has been designed. Phase One of the system consists of five quadrupoles and two bending magnets, and forms the pion collection section of the muon channel. It a1so serves as a stopped pion channel. The maximum solid angle of acceptance of this channel is 26 msr and the range of accepted momenta extends 17.5% on each side of the central momentum. For a 100 μA proton beam incident on a 10 cm long beryllium target, the calculated maximum stopping density of pions in an area of 25 cm x 25 cm is 1 x 108 n-(sec·g/cm2)-1 when the channel is operated at a central momentum of 100 MeV/c. A maximum muon stopping density of 7 x 106 μ-(sec·g/cm2)-1 can be obtained if the pions are separated by range absorption. Better muon beam purity is obtained by tuning the second half of the channel to 90 MeV/c to collect muons from the decay of pions in the backward direction when the first half is set at 160 MeV/c. In this case, a maximum muon stopping density of 1 x 106 μ-(sec·g/cm2)-1 can be obtained. If a bending magnet is placed after the Phase One system to separate the muons and the pions by momentum analysis, a calculated maximum muon stopping density of 2 x 106 μ-(sec·g/cm2)-1 can be obtained when the magnet is tuned to 85 MeV/c and the channel is set at 160 MeV/c. Phase Two of the design consists of a long straight alternating gradient section and an analyzing section. The straight section provides an extra 5.5 meter length for pion decay. When the central momentum of the pion collection system is 160 MeV/c and the straight section is tuned to optimize the number of mouns from the backward decay of pions, the calculated maximum muon stopping density in a 25 cm x 25 cm area is 1 x 107 μ-(sec·g/cm2)-1. The analyzing section consists of a 90° bending magnet and a quadrupole triplet. With the pion collection system and the straight section set as described above and the analyzing section tuned to 82 HeV/c, a calculated maximum stopping density is 3.2 x 106 μ-(sec·g/cm2)-1 in a 25 cm x 25 cm area and 1.1 x 106 μ-(sec·g/cm2)-1 in a 10 cm x 10 cm area. An average muon polarization of between 70% and 90% may be obtained. The yields of TI+ and μ+ are about three times larger than the TI- and μ- yields. The accuracy of the calculation procedures was checked by comparing calculated and measured values for a pion channel, designed and set up at the Lawrence Laboratory at Berkeley. The two sets of values were found in agreement to within experimental error.
Effect of emphasis on time-to-solution and verbal versus spatial stimuli on attribute identification performance
(1973) Wasilewski, Bohdan Kazimierz; Downing, John
Four hundred and thirteen students in twenty-four intact Grade XI classes, under the direction of their regular teachers, from three secondary schools in Victoria, B.C., participated in two concept learning experiments. The aim was to test (1) the effect of instructions which emphasize speed and (2) the effect of spatial versus verbal stimulus materials on performance on an attribute identification task. The stimuli were twenty cards representing either four or six two-value dimensions (shape, size, color, number; and, location, outline). Two problems, each of twenty cards, were contained in a booklet. The responses of Ss to the stimuli were observed in terms of the number of cards to solution. The results indicate that: (1) Ss who were instructed to work as quickly as possible solved proportionally fewer tasks and used more cards to solution in terms of a 5-point scale than Ss who were instructed to ignore time and to work as carefully as possible: and (2) Ss on verbal stimulus materials solved proportionally more tasks, achieved the solution with fewer card choices (in terms of a 15-point scale), and used fewer cards to solution (in terms of a 5-point scale), than Ss on spatial stimulus materials. These findings suggest that speed and "goodness" of a response may not be interchangeable attributes; that the use of speed instructions in either an experimental situation or in classroom testing is questionable; and that spatial and verbal stimulus materials representing the same construct may not elicit equivalent responses. The validity of generalizing the results from experimental studies of attribute identification with geometric stimuli to normal concept learning situations in the everyday life classroom is questioned.
Measuring attentional capacity
(1986) Weber, Alison Mary; Spellacy, Frank Jared
Studies of attentional function in normals and attentional problems in clinical populations, particularly closed head injury cases, strongly indicate that the crucial aspect of attentional difficulty is the limited amount of information a person can attend to or process within a given time. Within this context, the terms "attentional capacity" and "information processing capacity " are used interchangeably and are also very closely related to the concept of "working memory". Despite the reported prevalence of attentional problems among brain-impaired people, there is a dearth of appropriate clinical measures of attention. Those that do exist are limited in that they assume intact motor and/or speech response capacity which many brain-impaired people lack and they measure too narrow a range of capacity to be useful across the full clinical spectrum. The aim of the present study was to develop a measure that covers the full range of attentional capacity and accommodates the response deficits common in clinical populations. A measure called the Attentional Capacity Test (ACT) was developed in which processing demands are gradually increased across eight succeeding levels of difficulty. It involves the person listening to a series of numbers, mentally counting how many tar get numbers occur, and reporting their answer at the end of the series. The answer is always somewhere from 1 to 10, making the response one of multiple-choice format. Because the response is in multiple-choice format and given after the processing demands of the series are finished, the response mode and speed can be adjusted to patient requirements without affecting the processing demands of the task. The primary concern of the present study was to explore the validity of the ACT as a measure of information processing or attentional capacity. Using a sample of 64 normal young adults, performance on the ACT was compared to that on a relatively well-established measure of information processing, the Paced Auditory Serial Addition Test (PASAT), and also to a simple measure of working memory, the Digits Backward Test. Positive relationships between the ACT and both these tasks confirmed that the ACT measured attentional capacity. The fact that the ACT related only moderately to the PASAT may have been because the PASAT demands adding skill and quick vocal responses which the ACT does not. This interpretation was confirmed by finding that the PASAT was highly correlated to a measure of adding speed and accuracy while the ACT was only minimally related to this task. Passive memory span, as measured by the Digits Forward task, was not meaningfully related to performance on either the ACT or the PASAT. The construct validity of the ACT was further confirmed by comparing the ACT performance of nine brain-impaired patients to staff ratings of their attentional functioning in everyday life. A positive relation between the two measures was found for seven patients with diffuse injury but not for two patients with focal damage. The implications of these findings are discussed with reference to the future development of the ACT.
The experience of prayer within the context of depression: A phenomenological inquiry
(1999) Warkentin, Carrie Lynn; Hett, Geoffrey
This study used a phenomenological approach to investigate the experience of prayer in the lives of individuals who have also experienced depression. Interviews with the three women were transcribed and analysed to draw out recurring themes. A summary account of all three women's experiences shows the fundamental structure of the experience of prayer in the lives of individuals who have experienced depression. Recurring themes found in all three of the participants' experiences of prayer included the view of prayer as a process of growth initiated by a low point of desperation, trust and hope as essential to prayer, experiencing the positive physiological effects of prayer, finding meaning in life through prayer, a change from extrinsic to intrinsic values, and the importance of support from friends and a spiritual community which was connected to feeling supported by God. In addition, two of the three participants identified a gap between religiosity and spirituality in their experiences, and believed that their spiritual beliefs needed to guide their career choices. The results of this study are discussed in relation to other research in the area of prayer and psychological health. Implications for counsellors and counsellor educators are presented and recommendations are made for future research.
An experimental comparison of direct and indirect approaches to hypnosis using the Stanford hypnotic susceptibility scale, form C
(1986) Vernon-Wilkinson, Rosemary Ann; Spellacy, Frank Jared
Two experiments were conducted to test the hypothesis that subjects of low hypnotizability would respond better to hypnosis using indirect suggestion than hypnosis using direct suggestion. Subjects' scores on two hypnotizability scales were compared: one representing the direct approach to hypnotic suggestion; the other representing the indirect approach to hypnotic suggestion. The Stanford Hypnotic Susceptibility Scale, Form C (Weitzenhoffer & Hilgard, 1962) was used as the direct suggestion approach (termed the Stanford C scale). An indirect-suggestion version of the scale was constructed by the writer for use as the indirect-suggestion approach (termed the Victoria C scale). Subjects were given both scales, in counterbalanced order. After each scale, subjects were questioned regarding relative automaticity or compliance of responses. A preference questionnaire was given after testing to examine phenomenological differences between the two scales using different approaches. After testing, subjects were divided into three groups based on their Stanford C scale scores: a high hypnotizability group (scoring 9-12); a medium group (scoring 5-8); also divided hypnotizability group (0-6). Results hypnotizability and a low group (scoring 0-4). They were into two groups similarly: a higher group (7-12) and a lower hypnotizability indicated gained that the subjects higher scores using the of low indirect suggestion approach to hypnosis (the Victoria C scale), than the direct suggestion approach to hypnosis (the Stanford C scale), but only when the Victoria C scale was taken after the Stanford C scale. Subjects of high hypnotizability gained higher scores using the Stanford C scale, particularly when taken after the Victoria C scale. Results were interpreted to suggest that for these measurement scale test i terns, indirect suggestion approaches to hypnosis were more effective than direct suggestion for subjects of lower hypnotiiability. These findings apply only to this type of standardized measurement scale, and are not applicable to clinical hypnosis, in the form of hypnotherapy. These indirect-suggestion approaches may be used in a measurement scale of hypnotizability, particularly in clinical research. Such a scale would be acceptable to clinicians for clinical research, since the hypnotic techniques are similar to those used in clinical practice. The use of an indirect-suggestion measurement scale may be a more valid measure of hypnotizability when an experimental treatment using indirect approaches to hypnosis is used. However, for laboratory research using direct-suggestion hypnosis, subjects should be tested with a scale using direct suggestion. The results of the preference questionnaire indicated that most subjects rated the indirect version more favorably than the direct version overall. Even subjects who scored equally on each scale rated the indirect hypnosis version as more relaxing, 'further into hypnosis'; suggested effects more vivid; responses less compliant and more hypnotic in quality; the approach to use for therapy; and the approach which seemed generally more effective. This can have important implications. At present, the Stanford scales are scored purely on behavioral criteria; phenomenological experience is not considered. And yet it is the subjective experience which distinguishes hypnotic experience from non-hypnotic experience. The incorporation of experiential criteria into the scoring system for measurement scales is recommended. The scoring of the Stanford C scale is made on a behavioral response, and not the subject's perceived experience. Whether these behavioral responses are an adequate measure for an experience distinguished by its phenomenological experience is a question for further examination.
Ear preference in the dichotic presentation of patterned nonverbal stimuli
(1968) Spellacy, Frank Jared; Spreen, Otfried
Right ear superiority in the identification and recall of dichotically presented verbal sounds has been frequently demonstrated in right handed persons. This finding has been attributed to left cerebral hemisphere dominance for speech and the assumption that the crossed auditory neural paths are stronger than the ipsilateral ones. An analogous model has been proposed for nonverbal sounds. This model suggests that the left ear, and by implication the right cerebral hemisphere, shows a significant superiority in nonverbal auditory perception. The literature suggests that this conceptualization is too broad since some nonverbal sounds fail to show the expected ear difference. The left ear superiority has been shown most clearly when music was used as a stimulus. The intent of the present study was to replicate this finding using different experimental methods than have been used previously, to investigate the effect of varying length of the interstimulus interval, and to attempt to isolate those aspects of music which may be critical in demonstrating a right hemisphere functional superiority. Four types of stimuli were examined: music, rhythm, timbre, and pitch patterns. The latter three stimuli were selected to represent component parts of music. The experimental stimuli were presented one pair at a time. Each dichotic pair was followed by a single identification foil which was either a new sound or one of the members of the experimental pair. The subjects (S) identified the foil by responding yes or no. Ss were right handed young adults of both sexes who had shown a right ear superiority on a verbal dichotic listening test. Sixty-four Ss were assigned to one of two experimental groups. Group one had a five second interstimulus interval (I3I) separating the dichotic pair from the recognition sound; for group two this interval was twelve seconds. Two dependent variables were examined: number of correct responses and response time. A left ear superiority in identifying musical stimuli was found for the experimental group with short ISI but not for the group with long ISI. No significant ear difference was demonstrated for the other three stimulus conditions (rhythm, timbre, and pitch) in either time group. There was a significant overall tendency for Ss to make correct responses more rapidly to stimuli presented to the left ear as compared to the right ear. However, this difference was not statistically significant within any one stimulus condition. Overall performance, i.e., the number of correct identifications, was affected by type of stimulus and length of ISI. Recognition time was significantly affected by the type of stimulus, length of ISI, and sex of S. These results are interpreted in terms of left ear superiority for nonverbal stimuli under immediate memory conditions. Left ear superiority for nonverbal sounds apparently is subject to rapid decay since it can not be demonstrated under delayed recognition conditions. As predicted, an overall effect of left ear superiority was found for both the number of correct responses as well as response time. Supplementary analyses of the performance of Ss over time suggest that the phenomenon of left ear dominance is affected by decreasing attention.
Assessment of attention in children
(1988) Seidel, William Thomas; Joschko, Michael
Attention has been acknowledged as playing a central role in the processing of information. Various clinical populations such as head injured, learning disabled and "hyperactive" are thought to be particularly susceptible to difficulties in attention. Despite the fact that attention can also affect the validity and interpretation of test results, neuropsychological assessments rarely evaluate attention in an objective manner. This is primarily due to the limited availability of tests that assess attention per se.; particularly without requiring additional cognitive skills such as memory or arithmetic abilities. The present research examined the possibility of using a popular research paradigm (Continuous Performance Test; CPT) as a clinical measure of attention for children. The specific CPT developed (i.e., CCPT) required children to attend to letters which were presented individually on a computer monitor and respond whenever a predetermined target letter occurred. The CCPT consisted of two subtests each with individual targets and each lasting for 15 minutes. The task was administered to 128 "normal" children and 25 children diagnosed with Attention Deficit Disorder (ADD). The results of analyses on the, normative sample indicated that CCPT performance improved with age and was also related to teacher ratings of school performance. CCPT performance was found to be significantly correlated with some Wechsler Intelligence Scale for Children-Revised (WISC-R) subtests that have traditionally been found related to an "attention" factor and not significantly correlated with a WISC-R subtest which is poorly related to this "attention" factor. Analyses of data from the Conners Parent and Teacher Questionnaires indicated that CCPT performance was significantly correlated with those subscales related to attention, but not subscales related to nonattentional dimensions. Comparison of the ADD group and a control group matched by gender, age, IQ and SES indicated that the ADD group performed significantly more poorly on the CCPT. Furthermore, clinical cut-off scores were devised which identified 73.9% of the ADD group and 4.0% of the Normative sample as "impair ed". Medication that enhances attention was found to also improve CCPT performance in ADD children. Finally, analyses of both internal consistency and temporal stability provided preliminary support for adequate reliability of the CCPT.
Topological space and work situations
(1979) Safayeni, Farough Rassoulian; Bavelas, Alex
The structure and dynamics of goal oriented activity were considered with respect to particular task situations. An algebraic method was developed for the detection of the phenomenal parts or the sub-goals units within the activity structure. Further, the same method was used for the quantification of the extent to which the path to the goal was organized. These considerations led to the development of two hypotheses: one on the correspondence of the algebraic method to subjective experience, and another on preference for paths that were structurally similar to the task and were 'good' gestalts. A cognitive model of locomotion was developed to account for the dynamics of a person's movement within the activity structure. The model was based on a numerical representation of the person's experience of locational changes in the course of the activity. The correspondence of the model to subjective experience was expressed in several hypotheses under a central theme of a preference for the paths in which the differences between locomotional variations were maximized. All hypotheses were tested in the context of four experiments. The first experiment was designed to test the structural hypotheses, and the other three experiments were conducted to examine the various aspects of the locomotional model. The results of these experiments supported the relevance of both the algebraic method as well as the model of the relation of locomotion to activity .
Cognitive rigidity and flexibility: a neuropsychological study
(1981) Regard, Marianne; Spreen, Otfried
This study investigated the effects of imagery on flexibility and the relations among verbal and non-verbal and spontaneous and adaptive flexibility measures. Finally, the effects if brain damage on flexibility and imagery were investigated. Historical and more recent concepts of the cognitive rigidity-flexibility dimension were discussed with special emphasis on the effects of brain damage. Forty female and fourteen male volunteer students were tested with verbal and non-verbal flexibility tests. Measures of spontaneous flexibility were the Word Fluency Test and the Five Point Test and measures of adaptive flexibility were the Stroop Test and a newly introduced concept identification test, assessing imagery and interference concepts. Furthermore, a questionnaire to assess individual imagery styles was employed as well as the vocabulary and block design subtests of the WAIS. The results of brain damaged subjects were compared to a matched control group. Furthermore, z-score profiles were prepared to compare the test patterns between the different patient groups. Four dimensions of cognitive flexibility-rigidity were found in healthy subjects. Furthermore it was found that individual imagery styles had little influence on the performance in flexibility tests. A trend was showing that "habitual verbalizers" had no advantage in solving the tests and ad in fac more difficulty with the identification of non-verbal concepts. No significant gender effects were found. Brain damaged patients performed significantly poorer in all flexibility tests than normal subjects. Several test- and subject variables that effect the performance on flexibility tests were discussed. It was concluded that rigidity-flexibility measures represent different dimensions depending on stimulus mode and type of task. It was further concluded that behavioral rigidity-flexibility is not only the function of test variables, but also of various subject variables namely imagery style, intelligence, age, gender and brain damage. In healthy people, the performance on one test was not found to be predictive for the performance on another flexibility test. On the other hand, in brain damaged subjects rigid behavior seems to extend to a wider range of test performance. Finally, different performance patterns were described for different lesion sites in brain damaged.
Writing as ecology: "patterns which connect" academic writing to Gregory Bateson's ecological matrix of communication
(2003) Quigley, Sharon Frances; Oberg, Antoinette A.
Because writing is used so pervasively as a tool of thinking/learning/inquiring, embedding composition theory and praxis within an ecological framework can contribute to the development of ecologically sustainable paradigms. To develop this framework, I explore the resemblances between Gregory Bateson' s epistemological, ecological theories and writing using a method called abduction, which is a method of drawing comparisons between differing entities that Bateson advocated as a way to build insightful knowledge within and across disciplines and different ways of knowing. Extending the abductive comparison Bateson made between creative thinking and evolutionary processes, I compare writing as a tool of thinking/learning/inquiring and biological processes and explore how both exemplify information, communication, and organizational processes of creative pattern making. I experiment with creating a holistic dialectic between traditional, expository, academic writing and autobiographical, reflective, creative, and aesthetic writing and consider how my own writing might exemplify what I am proposing. I explore how opening to deeper questioning and holding the tension of "not knowing" allows the myriad, unknown, exquisitely complex interrelationships in which an inquiry is embedded to be more fully integrated and thus lead to more ecologically wise answers and actions.
An investigation of age differences in divided attention and intrahemispheric competition
(1981) Penner, Ronald Steven; Costa, Louis
Following several pi lot experiments on intrahemispheric competition a primary experiment was conducted to investigate adult age differences in divided attention and intrahemispheric competition. Right handed subjects performed a repetitive finger tapping task, with the right or left index finger, either alone or with a concurrent verbal task (Tongue Twisters, Verbal Fluency, or Sentence Repetition). All subjects were exposed to each of the three concurrent tasks with one right and one left hand trial within each concurrent task condition, and task and hand orders were counterbalanced. The subjects were instructed to divide their attention equally between the two tasks in concurrent task conditions. There were four control trials of single task tapping with each hand, and these trials were evenly spaced throughout the experiment from beginning to end. All trials were of 20 seconds duration with 30 second inter-trial intervals. Subjects tapped faster with the right than the left hand and young subjects tapped faster than older subjects. Tapping performance improved with practice, and improvement was similar for both hands and for each age group. All three verbal tasks interfered with concurrent finger tapping performance. The Tongue Twister task was associated with the greatest degree of interference while Verbal Fluency and Sentence Repetition were substantially less disrupting. Age differences in overall degree of interference were found for the Verbal Fluency and Sentence Repetition tasks. Patterns of intrahemispheric competition (greater right than left decline from baseline tapping) were found for each task, with Sentence Repetition providing the most powerful and consistent effects. There was a tendency for the Tongue Twister task to result in bilateral yet somewhat asymmetric tapping decrement. The post hoc establishment of a laterality criterion based on single task tapping performance resulted in more powerful findings of intrahemispheric competition, particularly for the Verbal Fluency condition. Age differences in intrahemispheric competition were not found for any of the concurrent task conditions. The results were discussed in terms of information processing and Kinsbourne's functional cerebral distance model. It was concluded that the elderly may require a greater portion of processing capacity to be allocated for the organization of the division of attention, and that intrahemispheric competition may be a stable phenomenon which does not represent a particular problem area in the elderly.
Office worker performance and satisfaction: the effects of office noise and individual characteristics
(1989) Ng, Cheuk Fan; Gifford, Robert
The effects of office noise on employees' satisfaction and performance are investigated in three studies, with attention given to individuals' characteristics that may modify these effects. 128 office workers completed questionnaires about themselves, their jobs, the physical features of and the perceptions of their offices. The information was used to test a causal model of employees' response to the work environment. To most respondents, particularly those in open-plan offices, their offices were too noisy and not private enough. They were distracted from work, had difficulty hearing others, and were irritated by noise. Noises made by office machines and telephones, and co-workers' conversations were distracting. The results of a path analysis were that job level affected office openness directly, office openness affected both aural distraction and conversational privacy directly, which in turn affected overall privacy. Finally, overall privacy affected satisfaction with the environment directly. Females and younger employees had less conversational privacy. Females also had more aural distractions. Unfortunately, the hypothesized model was rejected. There may be direct effects of (1) aural distraction on satisfaction, (2) job level on aural distraction, and (3) aural distraction on conversational privacy. Coworkers' conversations are a prime noise source, but their effects on office task performance have rarely been examined. In Experiment 1, the hypotheses that background conversations impaired performance, and that screeners performed better than non-screeners in the presence of irrelevant information and especially in high information rate settings are tested. A between-subjects factorial design (information rate, information relevance, stimulus screening) with a single control group was used. Sixty-one clerks performed simulated office tasks for 30-45 minutes. Subjects in the experimental groups heard a tape recording of a conversation. The conversations differed in information rate and information relevance. Subjects' stimulus screening abilities were measured with Mehrabian's Scale. The speed and the accuracy of each task were measured. Background conversation did not lower the performance of the tasks. Spelling speed was lower when the information was irrelevant. Spelling accuracy was affected by information rate, information relevance, and stimulus screening in combination. As predicted, non-screeners worked significantly more slowly overall and on spelling when irrelevant information was present. However, screeners were no faster than non-screeners in high information rate settings. Perhaps speech rate does not validly measure information rate. Consistent with previous findings, the background conversation made working less enjoyable and was fairly distracting. Individual differences in noise response must be considered, and yet have received little attention. In Experiment 2, the hypotheses that individuals perform best at the most preferred sound level and that personality may modify such relationship were tested. A within-subject repeated measures design was used. Twenty-eight data-entry operators' productivity (speed and accuracy) was measured in five one-hour sessions in which background office noise was presented at five levels. In the first session, each subject completed a sound sensitivity and an introversion-extraversion scale, and selected her most preferred sound level. All subjects preferred the lower noise levels (48-56 dBA). Extraverts chose higher sound levels than did introverts. Only the operators with more extreme scores on the introversion-extraversion rating scale produced most at the most preferred sound level, as predicted. Noise sensitive operators were clearly more accurate than were less-sensitive operators. Difficulty in recruiting office workers resulted in small samples. The use of single items as measures of some variables in the survey, questionable operationalization of information rate in Experiment 1, and the inability to reduce ambient noise to much lower levels in Experiment 2 pose some limitations to these findings. Compared with many laboratory experiments in which meaningless noise, unfamiliar tasks, and unrealistically high noise levels are used, the experiments have greater external validity.
Pattern masking and visual perception: assessing the effects of a structure and noise mask using the general recognition theory
(1999) Muis, Krista R.; Kadlec, Helena
A new paradigm was used to test the effects of a structure and noise mask on the perception of visual stimuli. These effects were examined using the General Recognition Theory (GRT) framework (Ashby & Townsend, 1986) to investigate how stimulus dimensions affect each other during perceptual processing. Participants identified one level on each of two dimensions of a stimulus. The stimuli were arcs of varying curvature and radial lines of varying orientation. The effects of the masks were examined as a function of stimulus onset asynchrony, and perception of the stimuli was assessed for perceptual separability, perceptual independence, and decisional separability, as defined within the GRT. The results indicate that the structure mask had little effect on perception of the stimuli in terms of dimensional interactions. The noise mask, however, had a considerable effect on perceptual independence. The results are discussed in terms of a stochastic model of GRT (Ashby, 1989).

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