Thesis (Ph. D.)--University of California, San Diego and San Diego State University, 2007. / Title from first page of PDF file (viewed April 4, 2007). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 128-166).

Thesis (Ph.D. in Psychology)--S.M.U., 2007. / Title from PDF title page (viewed Nov. 19, 2009). Source: Dissertation Abstracts International, Volume: 68-11, Section: B, page: 7695. Adviser: Alan S. Brown. Includes bibliographical references.

Thesis (doctoral)--Rheinisch-Westfälische Technischen Hochschule Aachen, 1999. / Includes bibliographical references (p. 133-142).

Thesis (Ph.D.)--Ohio University, June, 2008. / Abstract only has been uploaded to OhioLINK. Includes bibliographical references (leaves 70-79)

Visual long term memory (VLTM) research has shown that we are capable of learning a virtually infinite amount of visual information. At the same time, visual short term memory (VSTM) research has shown that there is a severe limitation in the amount of information we can simultaneously apprehend at a given time. How does the severe capacity limitation in the initial uptake of information influence the encoding of information into VLTM? To this date, there has been no direct test of such influence, and the effect of such limitation has been unclear. Here, we demonstrate that, across wide varieties of conditions, the severe-capacity limitation in VSTM dictates the encoding of information into VLTM by determining the "bandwidth" of information transfer. This finding has a substantial implication for the understanding of the role of severely-capacity limited VSTM in forming many types of VLTM representations. / 10000-01-01

The complexity of behaviour necessitates a clear and concise approach in order to comprehend its functioning. An example of such an approach is highlighted by the field of cybernetics. Cybernetic models have been used extensively throughout the various fields of Psychology but perhaps never more so as in the case of short term memory (STM). This particular field abounds with behavioural models and research workers are constantly developing new models or testing the universality of existing models. Universal validity is essential to the strength of the behavioural principles inherent in any model but unfortunately such validity tends to be neglected. The present study attempts to reconcile this position with reference to specific models of STM, with relation to the phenomena of eidetic imagery (EI). Certain studies concerning the incidence of EI in illiterate Africans have produced results which are contradictory to those obtained in the Western culture. Two of the most important contradictions concern the fact that the illiterate Africans experienced the absence of an age parameter on the occurrence of such imagery and the fact that the incidence of imagery was more extensive in the African culture. A reason for these contradictions was sought and it was reasoned that as eidetic images have been closely linked with memory images, it may, therefore, be assumed that these particular cultures may use EI as an aid to memory in the absence of written material. Further, it would not be unreasonable to assume that this visual imagery may tend to dominate the STM process and thereby challenge the universality of those memory models that proposed acoustic domination of this process. No work has been done in investigating the memory process of the Africans. Thus, a study which did so would not only test the universality of specific memory models but would also possibly throw more light on the memory process itself. In this particular study there were three specific aims; (a) to ascertain the relative incidence of EI on a cross-cultural level, (b) to assess the influence of EI on the memory process, and (c) to ascertain the extent to which principles of STM developed in the West applied to the African groups. The groups concerned in the study comprised two Xhosa groups and a European group. The European group (WS) was drawn from a White Student population at Rhodes University and was regarded as a control group. The equivalent literate Xhosa group (BS) was drawn from a Black Student population at the University of Fort Hare. The illiterate Xhosa group (RX) was drawn from a population of Red Xhosa people in the Transkei. Four tasks were administered to the groups with the cross-cultural variable carefully controlled as much as possible. The following comprised the four tasks; (a) eidetic imagery (b) auditory serial recall (c) visual serial recall and (d) an acoustic confusable task. Each subject commenced with the eidetic imagery task and was then confronted with a random presentation of the other three tasks. The EI task began with an after image task which was foIlowed by three selected pictures which comprised the EI task. After each picture presentation the subject was closely questioned as to the presence of imagery. Scoring was of a subjective nature. The visual and acoustic confusion tasks constituted serial presentation of ten items over six randomized trials. Each item was presented for 0,75 seconds with a negligible inter-item interval. The presentation order of the items was randomized throughout the trials. Presentation was by means of a preprogrammed 16mm colour film. Items were scored for correct serial position. The auditory task consisted of the serial presentation of ten items over six randomized trials. The items were once again randomized throughout the trials with regards to presentation order. The presentation speed was one word per second. The presentation was by means of a pre-programmed tape. Items were scored for correct serial position. The visual task was common to both language groups whilst the other two tasks correlated with the language group. Thus, the items in the auditory and acoustic confusion tasks were different for each language but an attempt was made to control this variable. The tasks were conducted in the subjects home language which was either Xhosa or English. It was assumed that the RX group would demonstrate a greater incidence of EI, irrespective of the age of the subject, and that imagery would be reflected in the recall performance of the memory tasks. It was suggested that imagery may determine or encourage the mode of storage that the subject employed, which, in this case, would be the visual modality. If so then it would be expected that visual storage would circumvent the detrimental influence of acoustic confusability. The Xhosa university group (BS ) was an unknown quantity but was included to ascertain whether there were any marked differences between the group and the other two. The results revealed that imagery was in fact more prevalent in the Xhosa groups whilst the WS group demonstrated a complete lack of EI but did report the presence of pictorial imagery (PI). However, imagery did not appear to function as an aid to memory. It seemed, however, that in certain instances it correlated with visual encoding. Generally the Xhosa subjects, especially with regards to the visual tasks, tended to encode visually whilst the WS group encoded auditorily. With reference to recall performance, it was found that in all instances the WS group demonstrated superior recall followed by the BS and RX groups in that order. There was a significant difference in the strength of recall between each of the groups. The results of the auditory and visual tasks were interpreted within the STM principles developed in the West. It was found that the WS group adhered to these principles thereby justifying its position as a central group. The BS group followed a similar pattern with exception to the recency effect which was much weaker in their case. The RX group reported the absence of any storage and rehearsal strategies and this was reflected in their poor recall performance. They too were characterized by a very weak recency effect. The interesting point arose, however, when the auditory and visual recency effects were compared. According to Crawder and Norton (1969) the influence or the precategorical acoustic store (PAS) on recall should be reflected by a comparatively stronger auditory recency effect. This trend was observed in relation to the WS group but not to the Xhosa groups who tended to demonstrate a stronger visual recency effect. It was therefore, suspected that PAS did not operate with the same effectiveness with the Xhosa subjects. In fact it was suggested that in the case of the Xhosa subjects the visual peripheral store may be stronger than PAS. Contrary to expectation all three groups exhibited acoustic confusion. This was expected of the WS group as the subjects preferred auditory storage , but not of the Xhosa subjects who preferred visual storage. It was suggested however, that in the case of the Xhosa subjects the visual storage technique would have to be abandoned immediately prior to or during recall as recall was necessarily in the auditory modality. The outcome of the experiment generally confirmed Doab's conclusions as to the incidence of imagery and its relation with memory. However, due to the Xhosa preference for visual storage and their stronger visual recency effect, Sperling's model was slightly modified. Conrad 's findings were, of course, substantiated.

The present work is an examination of the mechanisms underlying temporal processing in vision. Recent studies have shown that when observers are asked to identify two objects presented in rapid succession, identification of the first object is quite accurate, while identification of the second object is poor when it folows the first at very brief inter-target intervals (i.e. 200-500 ms). This second-target deficit is known as the attentional blink. According to bottleneck models, the attentional blink occurs because processing of the first target prevents the second target from gaining access to high-level processing. A strong prediction of this account is that if processing time for the first target is increased, the magnitude of the attentional blink should also increase. This prediction is confirmed in experiments. It is argued that these results strongly support bottleneck models as an account of the attentional blink in particular and of temporal processing more generally. / Arts, Faculty of / Psychology, Department of / Graduate

Experimental evidence was needed to help answer the question of whether the decrease in retention from Trial 1 to Trial 2 was caused by PI from Trial 1 decreasing retention of Trial 2, or by a primacy effect increasing retention of Trial 1 over the natural retention baseline of a S. The present experiment was designed to help answer this question.

abstract: Learning programming involves a variety of complex cognitive activities, from abstract knowledge construction to structural operations, which include program design,modifying, debugging, and documenting tasks. In this work, the objective was to explore and investigate the barriers and obstacles that programming novice learners encountered and how the learners overcome them. Several lab and classroom studies were designed and conducted, the results showed that novice students had different behavior patterns compared to experienced learners, which indicates obstacles encountered. The studies also proved that proper assistance could help novices find helpful materials to read. However, novices still suffered from the lack of background knowledge and the limited cognitive load while learning, which resulted in challenges in understanding programming related materials, especially code examples. Therefore, I further proposed to use the natural language generator (NLG) to generate code explanations for educational purposes. The natural language generator is designed based on Long Short Term Memory (LSTM), a deep-learning translation model. To establish the model, a data set was collected from Amazon Mechanical Turks (AMT) recording explanations from human experts for programming code lines. To evaluate the model, a pilot study was conducted and proved that the readability of the machine generated (MG) explanation was compatible with human explanations, while its accuracy is still not ideal, especially for complicated code lines. Furthermore, a code-example based learning platform was developed to utilize the explanation generating model in programming teaching. To examine the effect of code example explanations on different learners, two lab-class experiments were conducted separately ii in a programming novices’ class and an advanced students’ class. The experiment result indicated that when learning programming concepts, the MG code explanations significantly improved the learning Predictability for novices compared to control group, and the explanations also extended the novices’ learning time by generating more material to read, which potentially lead to a better learning gain. Besides, a completed correlation model was constructed according to the experiment result to illustrate the connections between different factors and the learning effect. / Dissertation/Thesis / Doctoral Dissertation Engineering 2020

This thesis presents the realization of an intelligent cognitive radio network that uses long short term memory (LSTM) neural network for sensing and predicting the spectrum activity at each instant of time. The simulation is done using Python and GNU Radio. The implementation is done using GNU Radio and Universal Software Radio Peripherals (USRP). Simulation results show that the confidence factor of opportunistic users not causing interference to licensed users of the spectrum is 98.75%. The implementation results demonstrate high reliability of the LSTM based cognitive radio network.