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Deal or no deal? Hold ‘em or fold ‘em? Buy, hold or sell? When faced with uncertainty, a wise decision-maker evaluates each option and chooses the one they deem most valuable. Scientists studying decision making processes have spent much theoretical and experimental effort formalizing a framework that captures how decision makers can maximize the amount of subjective value they accrue from such decisions. This thesis tested two hypotheses. The first was that subjective value guides our simplest and most common of motor actions similar to how it guides more deliberative economic decisions. The second was that subjective value is allocated across pre-motor regions of the brain to make our actions more efficient. To accomplish these goals, I adapted a paradigm used by behavioural economists for use in neurophysiological experiments in non-human primates. In our task, monkeys repeatedly make quick, orienting eye movements, known as saccades, to targets, which they learned through experience, had different values. In support of the hypothesis that subjective value influences simple motor actions, the speed with which monkeys responded, known as saccadic reaction time (SRT), and their saccadic choices to valued targets were highly correlated and therefore both acted as a behavioural measures of subjective value. Two complimentary results support the hypothesis that subjective value influences activity in the intermediate layers of the superior colliculus (SCi) – a well-studied brain region important to the planning and execution of saccades - to produce efficient actions. First, when saccades were elicited with microstimulation, we found that the timing and spatial allocation of pre-saccadic activity in the SC was shaped by subjective value. Second, the baseline preparatory activity and transient visual activity of SCi neurons prior to saccade generation was also influenced by subjective value. Our results can be incorporated into existing models of SC functioning that use dynamic neural field theory. I suggest that saccades of higher subjective value will result in higher activation of their associated neural field such that they will be more likely and more quickly selected. In summary, this thesis demonstrates that subjective value influences neural mechanisms, not only for deliberative decision making, but also for the efficient selection of simple motor actions. / Thesis (Ph.D, Neuroscience Studies) -- Queen's University, 2013-06-25 17:18:25.393

With new technology come new possibilities for the creation of artistic works. The invention of sound recording at end of the nineteenth century enabled musical performances to be “written” in the same manner as traditional, printed literature. The status of records as a form of writing and, moreover, as the material for further writing is demonstrated in the work of two hip hop artists, DJ Shadow and Cut Chemist, who assemble new, heteroglossic texts out of a wide array of sampled records. Two concerts, Product Placement (2004) and The Hard Sell (2008) – both of which have been memorialized on DVD – serve as fruitful examples of the potential for artistic production enabled by technology. Indeed, the genre of turntablism, which involves the live manipulation of vinyl records, requires the usage of technology in ways not intended by its original developers – a recurrent theme throughout the history of sound recording. By transforming the turntable from a passive playback device into an active compositional tool, turntablism collapses the distance between consumption and production and so turns the listener into a performer. Furthermore, the exclusive usage of 45 rpm records as the source texts for the two sets dramatizes theories of intertextuality while simultaneously tracing the constraints placed on such artistic piracy by the copyright regime. These texts entail more than just their cited musical content; they also involve visual components. These include not only the video imagery that accompanies and comments on the records being played, but also the physical performance of the DJs themselves and the spectacle of the attending crowds whose response to the music constitutes part of the text itself. Following a theoretical and historical background that will situate these works within the history of hip hop and literature in general, this study will explicate these two multimedia texts and reveal how they demonstrate a concern not only with the history of sound recording, but also such issues as the influence of technology on cultural production, the complication of authorship through intertextuality, and the relationship between culture and commerce. Above all, however, both the form and content of these two performances also serve to highlight the value of physical media as historical artifacts in the face of increasing challenges from incorporeal digital media.

This dissertation research explored the capabilities of neuronal networks grown on substrate integrated microelectrode arrays in vitro with emphasis on utilizing such preparations in three specific application domains: pharmacology and drug development, biosensors and neurotoxicology, and the study of burst and synaptic mechanisms. Chapter 1 details the testing of seven novel AChE inhibitors, demonstrating that neuronal networks rapidly detect small molecular differences in closely related compounds, and reveal information about their probable physiological effects that are not attainable through biochemical characterization alone. Chapter 2 shows how neuronal networks may be used to classify and characterize an unknown compound. The compound, trimethylol propane phosphate (TMPP) elicited changes in network activity that resembled those induced by bicuculline, a known epileptogenic. Further work determined that TMPP produces its effects on network activity through a competitive inhibition of the GABAA receptor. This demonstrates that neuronal networks can provide rapid, reliable warning of the presence of toxic substances, and from the manner in which the spontaneous activity changes provide information on the class of compound present and its potential physiological effects. Additional simple pharmacological tests can provide valuable information on primary mechanisms involved in the altered neuronal network responses. Chapter 3 explores the effects produced by a radical simplification of synaptic driving forces. With all synaptic interactions pharmacologically limited to those mediated through the NMDA synapse, spinal cord networks exhibited an extremely regular burst oscillation characterized by a period of 2.9 ± 0.3 s, with mean coefficients of variation of 3.7, 4.7, and 4.9 % for burst rate, burst duration, and inter-burst interval, respectively (16 separate cultures). The reliability of expression of this oscillation suggests that it may represent a fundamental mechanism of importance during periods of NMDA receptor dominated activity, such as embryonic and early postnatal development. NMDA synapse mediated activity produces a precise oscillatory state that allows the study of excitatory-coupled network dynamics, burst mechanisms, emergent network properties, and structure-function relationships.

International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California / The Central Multiplexer is a versatile data multiplexer designed to address emerging test requirements for recording data from many sources on digital rotary head recorders at high data rates. A modular design allows easy reconfiguration for airborne or laboratory use; simultaneous data input from 63 sources of data in any combination of PCM commutators, ARINC 429 buses, ARINC 629 buses, MIL- STD-1553 buses, and general-purpose high-speed serial data packets; simultaneous, independent programmable outputs to high-speed digital data recorders, quick-look displays, and engineering monitor and analysis systems; and setup and control from a remote panel, a dumb terminal, a laptop personal computer, a standalone test system, or a large control computer.

This study investigated the effects of verbal and graphic feedback alone and in combination with praise on the data-recording behavior of 12 direct care trainers (DCTs) who recorded their reinforcer deliveries as they interacted with mentally retarded clients. An additional variable examined was the effect of time of delivering feedback on subsequent data-recording behavior. Feedback was delivered by the experimenter. Correspondence checks were conducted and a three-phase multiple condition experimental design was used. All feedback conditions produced an observable difference in DCT data-recording behavior. Time of delivery of feedback also appeared to have an effect on the amount of data recorded by DCTs.

Adolescents with behavioral difficulties and emotional and behavior disorders (EBD) or other health impairment (OHI) have demonstrated deficits in reading, and these deficits appear to remain stable or worsen over time. Reading fluency is an essential skill for overall reading achievement, yet relatively few studies have addressed reading fluency intervention for adolescents, particularly adolescents with behavioral difficulties. This study used a multiple baseline across participants design to evaluate the effect of a repeated reading intervention on the reading fluency and comprehension skills of middle school students with reading difficulties and behavioral difficulties and EBD or OHI. The intervention involved repeated reading combined with an audio-recorded model and cues to read for comprehension. Working independently at a classroom computer, participants received six to nine minutes of daily supplemental fluency instruction over a four-week period. Instruction involved listening to an audio recording of a model reading a passage, receiving cues to read for understanding, reading the passage aloud while using the computer to record the reading, listening to the recording, and reading the passage aloud again while recording. Results indicated no functional relation between the intervention and the number of words correct per minute or the percentage of comprehension questions answered correctly. However, on-task behavior did improve during study session when compared with on-task behavior during regular classroom instruction. The findings of the study have implications for addressing the needs of adolescents with behavioral difficulties who have reading difficulties.

Trying to remember is a form of forgetting. Memory fades, changes meaning, and disappears over time. While trying to find other ways to preserve stories about my family, it occurred to me that I could recreate what I remember in clay. I am creating collections of physical mementos of the memories that fill my head, focusing mainly on my childhood. Remembering is in itself an act of forgetting, and thus this is my memory preservation kit. I am recording memories of my family for posterity in clay before I have a chance to forget.

The basal ganglia (BG) is a complex set of heavily interconnected nuclei located in the central part of the brain that receives inputs from the several areas of the cortex and projects via the thalamus back to the prefrontal and motor cortical areas. Despite playing a significant part in multiple brain functions, the physiology of the BG and associated disorders like dystonia remain poorly understood. Dystonia is a devastating condition characterized by ineffective, twisting movements, prolonged co-contractions and contorted postures. Evidences suggest that it occurs due to abnormal discharge patterning in BG-thalamocortocal (BGTC) circuitry. The central purpose of this study was to understand the electrophysiology of BGTC circuitry and its role in motor control and dystonia. Toward this goal, an advanced multi-target multi-unit recording and analysis system was utilized, which allows simultaneous collection and analysis of multiple neuronal units from multiple brain nuclei. Over the cause of this work, neuronal data from the globus pallidus (GP), subthalamic nucleus (STN), entopenduncular nucleus (EP), pallidal receiving thalamus (VL) and motor cortex (MC) was collected from normal, lesioned and dystonic rats under awake, head restrained conditions. The results have shown that the neuronal population in BG nuclei (GP, STN and EP) were characterized by a dichotomy of firing patterns in normal rats which remains preserved in dystonic rats. Unlike normals, neurons in dystonic rat exhibit reduced mean firing rate, increased irregularity and burstiness at resting state. The chaotic changes that occurs in BG leads to inadequate hyperpolarization levels within the VL thalamic neurons resulting in a shift from the normal bursting mode to an abnormal tonic firing pattern. During movement, the dystonic EP generates abnormally synchronized and elongated burst duration which further corrupts the VL motor signals. It was finally concluded that the loss of specificity and temporal misalignment between motor neurons leads to corrupted signaling to the muscles resulting in dystonic behavior. Furthermore, this study reveals the importance of EP output in controlling firing modes occurring in the VL thalamus.