From Working Memory to Long-term Memory and Back: Linked but Distinct

Neural models have proposed how short-term memory (STM) storage in working memory and long-term memory (LTM) storage and recall are linked and interact, but are realized by different mechanisms that obey different laws. The authors' data can be understood in the light of these models, which suggest that the authors may have gone too far in obscuring the differences between these processes.

A Memory Model for Concept Hierarchy Representation and Commonsense Reasoning

Most associative memory models perform one level mapping between predefined sets of input and output patterns1 and are unable to represent hierarchical knowledge. Complex AI systems allow hierarchical representation of concepts, but generally do not have learning capabilities. In this paper, a memory model is proposed which forms concept hierarchy by learning sample relations between concepts. All concepts are represented in a concept layer. Relations between a concept and its defining lower level concepts, are chunked as cognitive codes represented in a coding layer. By updating memory contents in the concept layer through code firing in the coding layer, the system is able to perform an important class of commonsense reasoning, namely recognition and inheritance.

Sequential Memory with ART: A Self-Organizing Network Capable of Learning Sequences of Patterns

A model which extends the adaptive resonance theory model to sequential memory is presented. This new model learns sequences of events and recalls a sequence when presented with parts of the sequence. A sequence can have repeated events and different sequences can share events. The ART model is modified by creating interconnected sublayers within ART's F2 layer. Nodes within F2 learn temporal patterns by forming recency gradients within LTM. Versions of the ART model like ART I, ART 2, and fuzzy ART can be used.

Extracted Memory from Temporal Patterns Using Adaptive Resonance and Recurrent Network

We can recognize objects through receiving continuously huge temporal information including redundancy and noise, and can memorize them. This paper proposes a neural network model which extracts pre-recognized patterns from temporally sequential patterns which include redundancy, and memorizes the patterns temporarily. This model consists of an adaptive resonance system and a recurrent time-delay network. The extraction is executed by the matching mechanism of the adaptive resonance system, and the temporal information is processed and stored by the recurrent network. Simple simulations are examined to exemplify the property of extraction.

Neural Models of Temporally Organized Behaviors: Handwriting Production and Working Memory

Advanced Research Projects Agency (ONR N00014-92-J-4015); Office of Naval Research (N00014-91-J-4100, N00014-92-J-1309)

Laminar Cortical Dynamics of Cognitive and Motor Working Memory, Sequence Learning and Performance: Toward a Unified Theory of How the Cerebral Cortex Works

How do the layered circuits of prefrontal and motor cortex carry out working memory storage, sequence learning, and voluntary sequential item selection and performance? A neural model called LIST PARSE is presented to explain and quantitatively simulate cognitive data about both immediate serial recall and free recall, including bowing of the serial position performance curves, error-type distributions, temporal limitations upon recall, and list length effects. The model also qualitatively explains cognitive effects related to attentional modulation, temporal grouping, variable presentation rates, phonemic similarity, presentation of non-words, word frequency/item familiarity and list strength, distracters and modality effects. In addition, the model quantitatively simulates neurophysiological data from the macaque prefrontal cortex obtained during sequential sensory-motor imitation and planned performance. The article further develops a theory concerning how the cerebral cortex works by showing how variations of the laminar circuits that have previously clarified how the visual cortex sees can also support cognitive processing of sequentially organized behaviors.

Working Memory Networks for Learning Multiple Groupings of Temporarily Ordered Events: Applications to 3-D Visual Object Recognition

Working memory neural networks are characterized which encode the invariant temporal order of sequential events that may be presented at widely differing speeds, durations, and interstimulus intervals. This temporal order code is designed to enable all possible groupings of sequential events to be stably learned and remembered in real time, even as new events perturb the system. Such a competence is needed in neural architectures which self-organize learned codes for variable-rate speech perception, sensory-motor planning, or 3-D visual object recognition. Using such a working memory, a self-organizing architecture for invariant 3-D visual object recognition is described that is based on the model of Seibert and Waxman [1].

Working Memory Networks for Learning Temporal Order, with Application to 3-D Visual Object Recognition

Working memory neural networks are characterized which encode the invariant temporal order of sequential events. Inputs to the networks, called Sustained Temporal Order REcurrent (STORE) models, may be presented at widely differing speeds, durations, and interstimulus intervals. The STORE temporal order code is designed to enable all emergent groupings of sequential events to be stably learned and remembered in real time, even as new events perturb the system. Such a competence is needed in neural architectures which self-organize learned codes for variable-rate speech perception, sensory-motor planning, or 3-D visual object recognition. Using such a working memory, a self-organizing architecture for invariant 3-D visual object recognition is described. The new model is based on the model of Seibert and Waxman (1990a), which builds a 3-D representation of an object from a temporally ordered sequence of its 2-D aspect graphs. The new model, called an ARTSTORE model, consists of the following cascade of processing modules: Invariant Preprocessor --> ART 2 --> STORE Model --> ART 2 --> Outstar Network.

Normal and Amnesis Learning, Recognition, and Memory by a Neural Model of Cortico-Hippocampal Interactions

The processes by which humans and other primates learn to recognize objects have been the subject of many models. Processes such as learning, categorization, attention, memory search, expectation, and novelty detection work together at different stages to realize object recognition. In this article, Gail Carpenter and Stephen Grossberg describe one such model class (Adaptive Resonance Theory, ART) and discuss how its structure and function might relate to known neurological learning and memory processes, such as how inferotemporal cortex can recognize both specialized and abstract information, and how medial temporal amnesia may be caused by lesions in the hippocampal formation. The model also suggests how hippocampal and inferotemporal processing may be linked during recognition learning.

Store Working Memory Networks for Storage and Recall of Arbitrary Temporal Sequences

Neural network models of working memory, called Sustained Temporal Order REcurrent (STORE) models, are described. They encode the invariant temporal order of sequential events in short term memory (STM) in a way that mimics cognitive data about working memory, including primacy, recency, and bowed order and error gradients. As new items are presented, the pattern of previously stored items is invariant in the sense that, relative activations remain constant through time. This invariant temporal order code enables all possible groupings of sequential events to be stably learned and remembered in real time, even as new events perturb the system. Such a competence is needed to design self-organizing temporal recognition and planning systems in which any subsequence of events may need to be categorized in order to to control and predict future behavior or external events. STORE models show how arbitrary event sequences may be invariantly stored, including repeated events. A preprocessor interacts with the working memory to represent event repeats in spatially separate locations. It is shown why at least two processing levels are needed to invariantly store events presented with variable durations and interstimulus intervals. It is also shown how network parameters control the type and shape of primacy, recency, or bowed temporal order gradients that will be stored.

Low power predictable memory and processing architectures

Great demand in power optimized devices shows promising economic potential and draws lots of attention in industry and research area. Due to the continuously shrinking CMOS process, not only dynamic power but also static power has emerged as a big concern in power reduction. Other than power optimization, average-case power estimation is quite significant for power budget allocation but also challenging in terms of time and effort. In this thesis, we will introduce a methodology to support modular quantitative analysis in order to estimate average power of circuits, on the basis of two concepts named Random Bag Preserving and Linear Compositionality. It can shorten simulation time and sustain high accuracy, resulting in increasing the feasibility of power estimation of big systems. For power saving, firstly, we take advantages of the low power characteristic of adiabatic logic and asynchronous logic to achieve ultra-low dynamic and static power. We will propose two memory cells, which could run in adiabatic and non-adiabatic mode. About 90% dynamic power can be saved in adiabatic mode when compared to other up-to-date designs. About 90% leakage power is saved. Secondly, a novel logic, named Asynchronous Charge Sharing Logic (ACSL), will be introduced. The realization of completion detection is simplified considerably. Not just the power reduction improvement, ACSL brings another promising feature in average power estimation called data-independency where this characteristic would make power estimation effortless and be meaningful for modular quantitative average case analysis. Finally, a new asynchronous Arithmetic Logic Unit (ALU) with a ripple carry adder implemented using the logically reversible/bidirectional characteristic exhibiting ultra-low power dissipation with sub-threshold region operating point will be presented. The proposed adder is able to operate multi-functionally.

History, revolution and the British popular novel: historical fiction in the romantic age

“History, Revolution and the British Popular Novel” takes as its focus the significant role which historical fiction played within the French Revolution debate and its aftermath. Examining the complex intersection of the genre with the political and historical dialogue generated by the French Revolution crisis, the thesis contends that contemporary fascination with the historical episode of the Revolution, and the fundamental importance of history to the disputes which raged about questions of tradition and change, and the meaning of the British national past, led to the emergence of increasingly complex forms of fictional historical narrative during the “war of ideas.” Considering the varying ways in which novelists such as Charlotte Smith, William Godwin, Mary Robinson, Helen Craik, Clara Reeve, John Moore, Edward Sayer, Mary Charlton, Ann Thomas, George Walker and Jane West engaged with the historical contexts of the Revolution debate, my discussion juxtaposes the manner in which English Jacobin novelists inserted the radical critique of the Jacobin novel into the wider arena of history with anti-Jacobin deployments of the historical to combat the revolutionary threat and internal moves for socio-political restructuring. I argue that the use of imaginative historical narrative to contribute to the ongoing dialogue surrounding the Revolution, and offer political and historical guidance to readers, represented a significant element within the literature of the Revolution crisis. The thesis also identifies the diverse body of historical fiction which materialised amidst the Revolution controversy as a key context within which to understand the emergence of Scott’s national historical novel in 1814, and the broader field of historical fiction in the era of Waterloo. Tracing the continued engagement with revolutionary and political concerns evident in the early Waverley novels, Frances Burney’s The Wanderer (1814), William Godwin’s Mandeville (1816), and Mary Shelley’s Valperga (1823), my discussion concludes by arguing that Godwin’s and Shelley’s extension of the mode of historical fiction initially envisioned by Godwin in the revolutionary decade, and their shared endeavour to retrieve the possibility enshrined within the republican past, appeared as a significant counter to the model of history and fiction developed by Walter Scott in the post-revolutionary epoch.

Exploring the Zionist evolution of Robert Briscoe: History and memory

Robert Briscoe was the Dublin born son of Lithuanian and German-Jewish immigrants. As a young man he joined Sinn Féin and was an important figure in the War of Independence due to a role as one of the IRA’s main gun-procuring agents. He took the anti-Treaty side during an internecine Civil War, mainly due to the influence of Eamon de Valera and retained a filial devotion towards him for the rest of his life. In 1926 he was a founding member of Fianna Fáil, de Valera’s breakaway republican party, which would dominate twentieth-century Irish politics. He was first elected as a Fianna Fáil T.D. (Teachta Dála, Deputy to the Dáil) in 1927, and successfully defended his seat eleven times becoming the first Jewish Lord Mayor of Dublin in 1956, an honour that was repeated in 1961. On this basis alone, it can be argued that Briscoe was a significant presence in an embryonic Irish political culture; however, when his role in the 1930s Jewish immigration endeavor is acknowledged, it is clear that he played a unique part in one of the most contentious political and social discourses of the pre-war years. This was reinforced when Briscoe embraced Zionism in a belated realisation that the survival of his European co-religionists could only be guaranteed if an independent Jewish state existed. This information is to a certain degree public knowledge; however, the full extent of his involvement as an immigration advocate for potential Jewish refugees, and the seniority he achieved in the New Zionist Organisation (Revisionists) has not been fully recognised. This is partly explicable because researchers have based their assessment of Briscoe on an incomplete political archive in the National Library of Ireland (NLI). The vast majority of documentation pertaining to his involvement in the immigration endeavor has not been available to scholars and remains the private property of Robert Briscoe’s son, Ben Briscoe. The lack of immigration files in the NLI was reinforced by the fact that information about Briscoe’s Revisionist engagement was donated to the Jabotinsky Institute in Tel Aviv and can only be accessed physically by visiting Israel. Therefore, even though these twin endeavors have been commented on by a number of academics, their assessments have tended to be based on an incomplete archive, which was supplemented by Briscoe’s autobiographical memoir published in 1958. This study will attempt to fill in the missing gaps in Briscoe’s complex political narrative by incorporating the rarely used private papers of Robert Briscoe, and the difficult to access Briscoe files in Tel Aviv. This undertaking was only possible when Mr.Ben Briscoe graciously granted me full and unrestricted access to his father’s papers, and after a month-long research trip to the Jabotinsky Institute in Tel Aviv. Access to this rarely used documentation facilitated a holistic examination of Briscoe’s complex and multifaceted political reality. It revealed the full extent of Briscoe’s political and social evolution as the Nazi instigated Jewish emigration crisis reached catastrophic proportions. He was by turn Fianna Fáil nationalist, Jewish immigration advocate and senior Revisionist actor on a global stage. The study will examine the contrasting political and social forces that initiated each stage of Briscoe’s Zionist awakening, and in the process will fill a major gap in Irish-Jewish historiography by revealing the full extent of his Revisionist engagement.

The student bullying of teachers in Irish second level schools: exploring the influence of historical low state intervention in education on the development of contemporary policy responses in Ireland

The student bullying of teachers (SBT) is a distinct and complex form of bullying with a multiplicity of diverse, changeable and intersecting causes which is experienced by and affects teachers in a variety of ways. SBT is both a national and an international phenomenon which is under-recognised in academic, societal and political spheres, resulting in limited conceptual understanding and awareness of the issue. This study explores teachers’ experiences of SBT behaviours in Irish second level schools as well as teachers’ perceptions regarding training, policies and supports in Ireland to address the issue. Specifically, the study seeks to explore the influence of historical low State intervention in education on contemporary policies and supports to deal with SBT in Ireland. A mixed methods approach involving a survey of 531 second level school teachers and 17 semi-structured interviews with teachers, Year Heads and representatives from teacher trade unions and school management bodies was employed to collect and analyse data. Findings indicate that SBT behaviours are prevalent in many forms in Irish second level schools. The hidden nature of the phenomenon has simultaneously contributed to and is reinforced by limited understanding of the issue as well as teachers’ reluctance to disclose their experiences. Findings reveal that teachers perceive the contemporary policies, training and support structures in Ireland to be inadequate in equipping them to effectively deal with SBT. State intervention in addressing SBT behaviours to date, has been limited, therefore many teachers are forced to respond to the issue based on their own initiatives and assumptions rather than from an informed critically reflective approach, supported by national guidelines and sufficient State investment. This has resulted in a piecemeal, un-coordinated and ad-hoc approach to SBT in Irish schools both in terms of teachers’ management of SBT behaviours and with respect to the supports extended to staff. The potential negative consequences of SBT behaviours on teachers’ wellbeing and professional performance and thus, on the education system itself, underlines the need for a strategic, evidence-based, resourced and integrated approach which includes, as a pivotal component, consultation with teachers, whose contribution to the process is crucial.

Functional neuroimaging of autobiographical memory.

Functional neuroimaging studies of autobiographical memory have grown dramatically in recent years. These studies are important because they can investigate the neural correlates of processes that are difficult to study using laboratory stimuli, including: (i) complex constructive processes, (ii) recollective qualities of emotion and vividness, and (iii) remote memory retrieval. Constructing autobiographical memories involves search, monitoring and self-referential processes that are associated with activity in separable prefrontal regions. The contributions of emotion and vividness have been linked to the amygdala and visual cortex respectively. Finally, there is evidence that recent and remote autobiographical memories might activate the hippocampus equally, which has implications for memory-consolidation theories. The rapid development of innovative methods for eliciting personal memories in the scanner provides the opportunity to delve into the functional neuroanatomy of our personal past.