no / This study aimed to determine if response times gathered during perimetry can be exploited within a thresholding algorithm to improve the speed and accuracy of the test. Frequency of seeing (FoS) curves were measured at 24 locations across the central 30° of the visual field of 10 subjects using a Method of Constant Stimuli, with response times recorded for each presentation. Spatial locations were interleaved, and built up over multiple 5-min blocks, in order to mimic the attentional conditions of clinical perimetry. FoS curves were fitted to each participant’s data for each location, and response times derived as a function of distance-from-threshold normalised to the slope of each FoS curve. This data was then used to derive a function for the probability of observing response times given the distance-from-threshold, and to seed simulations of a new test procedure (BURTO) that exploited the probability function for stimulus placement. Test time and error were then simulated for patients with various false response rates. When compared with a ZEST algorithm, simulations revealed that BURTO was about one presentation per location faster than ZEST, on average, while sacrificing less precision and bias in threshold estimates than simply terminating the ZEST earlier. Despite response times varying considerably for a given individual and their thresholds, response times can be exploited to reduce the number of presentations required in a visual field test without loss of accuracy.

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The conversion of a memory from an initially fragile state to an enduring representation requires cellular, molecular, and systems-level brain network changes. This reorganization is hypothesized to involve time-dependent neuroanatomical changes that may differentially support some types of remote versus recent memory, and may also influence the latency to decide and complete responses during retrieval. To quantify the timecourse of learning and retrieval after different retention durations, a paradigm is developed to measure in humans and monkeys the retrieval speed of visuomotor associations, which require an intact hippocampus for initial acquisition but not for retrieval after days or weeks. Two components of retrieval speed, a decision time to initiate movement and a velocity-dependent movement completion time to complete a motor response, are shown to change differently relative to a pre-retention baseline. Movement completion times decrease across repetitions within single learning session, and continue to decrease from the level reached at the end of learning following retention. Decision times also decrease within the learning session, but increase on the first post-retention retrieval attempt as a function of retention interval duration. Extensive practice is required for decision times to reach a level below that obtained at the end of learning, and the transition from a long- to short-latency decision depends on the number and spacing of practice trials. The findings are discussed in a framework in which post-retention processing time is influenced by the speed of visual identification, the time to retrieve the associative relationship from long-term memory, and the time to plan and execute a motor response. The creation of sparser, long-lasting visual form representations and strengthened cortico-striatal connections predict behavioral efficiency gains in visual identification and motor responses after learning. Decision times could be fast and automatic following extensive practice when the neural representation may become stored permanently in cortico-cortical and cortico-striatal linkages, or could increase after retention because of several cognitive and neural factors, including interference and frontal inhibition of the hippocampal system to prevent new learning before choice feedback. The experimental results are discussed in the context of the existing literature on memory consolidation.

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

This investigation was designed to determine relative effects of monetary reward and knowledge of results on complex-choice reaction time tasks. Subjects were twenty-five male and thirty-two female undergraduate students. Apparatus consisted of nine stimulus lights and eight response keys. Subjects were required to add the number of lights presented, subtract the sum from a constant, and press the correctly numbered response key. Reward subjects received twenty-five cents for responses faster than a predetermined criterion, and twenty-five cents was deducted for slower responses. Knowledge of results subjects were told their reaction times after each trial. Results indicated (1) no significant differences between any conditions, (2) a significant overall practice effect (.01 level), and (3) that males were significantly faster than females (.01 level).

Numerous studies have looked at cognitive processing, more specifically attention, and its important role in various dynamic and static movements. Research on attentional demands in sport is an expanding area with studies now being done on athletes revealing the role of cognitive factors in the execution of motor movements in sports. Objective: the purpose of this study was to determine the attentional demands of a delivery in curling using a classic probe technique with a verbal response time and by measuring numerous performance variables. Subjects: ten healthy skilled curling players and nine healthy novice curling players undertook an auditory probe reaction time concurrently with a delivery in curling. Method: Sixty shots were executed with ten shots for each of the three phases of the shot, in all 30 take outs and 30 draws were done by each participant. The first phase when the player comes out of the “hack”, the second phase of the throw was when the player slid across the “t-line”. The third phase is when the player arrives near the line of Hog and releases the stone. Results: results revealed that reaction times were longer at phase 1 of the delivery for all subjects. The attentional demands for the draw and take out were highest at the phase one of the delivery, furthermore, compared to the draw, a significant rise of RT was seen in phase 3 of the take out shot. Significant differences were also found between the two experimental groups, with the most notable ones being that expert had a better shot success and a slower delivery time than the novice group. Conclusion: These results will lead to a better understanding of the attentional demands of two key shots in the sport of Curling and help curling coaches and teachers, as well as the players of the sport to know more about the attentional demands of the execution movement of the sport. This study also opens a new and interesting perspective on the importance of attention while performing motor tasks that are more complex and demanding.

Numerous studies have looked at cognitive processing, more specifically attention, and its important role in various dynamic and static movements. Research on attentional demands in sport is an expanding area with studies now being done on athletes revealing the role of cognitive factors in the execution of motor movements in sports. Objective: the purpose of this study was to determine the attentional demands of a delivery in curling using a classic probe technique with a verbal response time and by measuring numerous performance variables. Subjects: ten healthy skilled curling players and nine healthy novice curling players undertook an auditory probe reaction time concurrently with a delivery in curling. Method: Sixty shots were executed with ten shots for each of the three phases of the shot, in all 30 take outs and 30 draws were done by each participant. The first phase when the player comes out of the “hack”, the second phase of the throw was when the player slid across the “t-line”. The third phase is when the player arrives near the line of Hog and releases the stone. Results: results revealed that reaction times were longer at phase 1 of the delivery for all subjects. The attentional demands for the draw and take out were highest at the phase one of the delivery, furthermore, compared to the draw, a significant rise of RT was seen in phase 3 of the take out shot. Significant differences were also found between the two experimental groups, with the most notable ones being that expert had a better shot success and a slower delivery time than the novice group. Conclusion: These results will lead to a better understanding of the attentional demands of two key shots in the sport of Curling and help curling coaches and teachers, as well as the players of the sport to know more about the attentional demands of the execution movement of the sport. This study also opens a new and interesting perspective on the importance of attention while performing motor tasks that are more complex and demanding.

In this study I investigated whether the strength in the manual response for emotional and neutral stimulus search arrays can explain some of the difference in reaction times (RT:s) for emotional stimuli, or not. Earlier, perceptual, cognitive and attentional processes has mostly been used to explain the variance in RT:s. Thirtythree individuals were asked to, as fast as possible, detect a target picture among distractor pictures in 3 rows x 4 columns arranged search arrays. The pictures were categorized in fear relevant animals (snake, spider) and neutral animals (cat). The results showed, more correct responses for cat target. No correlation between strength and fear relevant target picture was found. This can partly be explained by that RT:s and force (Newton) was measured at different time sets with different buttons. The results show that the use of different response buttons results in a difference in the heartbeat frequency.

Numerous studies have looked at cognitive processing, more specifically attention, and its important role in various dynamic and static movements. Research on attentional demands in sport is an expanding area with studies now being done on athletes revealing the role of cognitive factors in the execution of motor movements in sports. Objective: the purpose of this study was to determine the attentional demands of a delivery in curling using a classic probe technique with a verbal response time and by measuring numerous performance variables. Subjects: ten healthy skilled curling players and nine healthy novice curling players undertook an auditory probe reaction time concurrently with a delivery in curling. Method: Sixty shots were executed with ten shots for each of the three phases of the shot, in all 30 take outs and 30 draws were done by each participant. The first phase when the player comes out of the “hack”, the second phase of the throw was when the player slid across the “t-line”. The third phase is when the player arrives near the line of Hog and releases the stone. Results: results revealed that reaction times were longer at phase 1 of the delivery for all subjects. The attentional demands for the draw and take out were highest at the phase one of the delivery, furthermore, compared to the draw, a significant rise of RT was seen in phase 3 of the take out shot. Significant differences were also found between the two experimental groups, with the most notable ones being that expert had a better shot success and a slower delivery time than the novice group. Conclusion: These results will lead to a better understanding of the attentional demands of two key shots in the sport of Curling and help curling coaches and teachers, as well as the players of the sport to know more about the attentional demands of the execution movement of the sport. This study also opens a new and interesting perspective on the importance of attention while performing motor tasks that are more complex and demanding.

A series of 3-alkyl and 3-aryl-5-hydroxy-5-trichloromethyl-4,5-dihydro-1Hpirazoles-1-carboxiamide that possess biological activity they were synthesized, in good yeld, through the cyclocondensation, in microwaves, of 4-alcoxi-1,1,1-trihalometyl-3alquen-2-onas with semicarbazyde chloride using MeOH/H2O as solvent. The advantage obtained with the use of irradiation of microwaves in relation to the classic methodology it is the decrease of the time reacional and revenue increase as it will be demonstrated. / Uma série de 3-alquil(aril) 5-hidroxi 5-triclorometil-4,5-diidropirazol-1-carboxiamida, que possuem atividade biológica foram sintetizadas, em bons rendimentos, através da ciclocondensação, em microondas, de 4-alcoxi-1,1,1-trialometil-3-alquen-2-onas com cloreto de semicarbazida e MeOH/H2O como solvente. A vantagem obtida com o uso de irradiação de microondas em relação à metodologia clássica é a diminuição do tempo reacional e aumento de rendimento como será demonstrado.