Verbal Discrimination Learning as a Function of Anxiety and Task Difficulty

Several studies have reported data bearing on the relationship between anxiety and various measures of discriminative behavior. Work by Spence and his associates (3, 4) seems uniformly to suggest that higher anxiety levels are associated with superior performance in differential eye-lid conditioning while the work of Hilgard et al (2) demonstrates impaired performance of high-anxiety Ss in the differential eyelid-conditioning situation. It must be noted that these studies involved relatively simple tasks. There is, however, some suggestion from perceptual studies involving somewhat more complex response measures (and where notably competing response tendencies were more prevalent) that discriminative performance is also impaired in the case of high-anxiety Ss (1). The experiment to be reported utilized verbal discrimination learning as the task. It has been previously reported that rate of verbal discrimination learning is inversely related to difficulty of the task where intra-task similarity defines the difficulty level (6). In addition to the above type of task difficulty variable the present work incorporated an anxiety variable in an attempt to determine what relationship exists between anxiety and discrimination learning of a more complex nature. Further, any interactions which might obtain between anxiety level and difficulty of task may be noted within the present design

Factors Affecting Knowledge Sharing in Virtual Learning Teams (VLTs) in Distance Education

This study asserts that knowledge sharing (a component of knowledge management) in distance education virtual learning teams (VLTs) is important for successful collaborative learning and that various factors characterizing person and environment can impact VLT members\u27 knowledge sharing behavior. Factors under the category of person are VLT members\u27 competencies for working on VLTs, and their learning goal orientation and performance goal orientation. Factors under VLT environment are social presence in the VLT, the VLT learning community, satisfaction with the VLT, task type, and instructor strategies. Knowledge sharing is defined as a behavior in which VLT members impart their expertise, insight, or understanding to other members in the VLT or to the entire team, intending for the recipients to have that knowledge in common with themselves, the sharers. The study used Bandura\u27s (1986) model of triadic reciprocal causation as a theoretical framework. The model is suitable for this research because it considers relationships between person, environment, and behavior. First, the study identified variables that are directly related to knowledge sharing. Next, the study validated those constructs. After the constructs had been validated, they were entered into a knowledge sharing measurement model. The study empirically tested a measurement model with five latent variables, taking into account the measurement error. Next, the study cross-validated the model with multiple groups drawn from the same sample. The sample consisted of data from 1,374 participants matriculated in graduate and undergraduate programs at an online university. The data were analyzed using split sample methodology, multiple regression analysis, and structural equation modeling techniques (factor analysis and latent variable structural equation modeling- SEM). The study\u27s findings suggest that there is a direct predictive relationship between knowledge sharing and competencies for working on VLTs, learning environment, social presence, task type, and mediating relationships for learning community, social presence, and task type in the knowledge sharing model. This study contributes to research, theory, and practice. It concludes by presenting a knowledge sharing model that can be reevaluated with distance education student populations at various kinds of distance education institutions

Demographics imputation in marketing sector by means of machine learning

Internship Report presented as the partial requirement for obtaining a Master's degree in Data Science and Advanced Analytics, specialization in Data ScienceThe goal of this project is to develop a predictive model in order to impute missing values in data collected through surveys (demographics data) and evaluate its performance. Currently there are two existing issues: demographics data for each user is either incomplete or missing entirely. Current POC is an attempt to exploit the capabilities of machine learning in order to impute missing demographics data. Data cleaning, normalization, feature selection was performed prior to applying sampling techniques and training several machine learning models. The following machine learning models were trained and tested: Random Forest and Gradient Boosting. After, the metrics appropriate for the current business purposes were selected and models’ performance was evaluated. The results for the targets ‘Ethnicity’, ‘Hispanic’ and ‘Household income’ are not within the acceptable range and therefore could not be used in production at the moment. The metrics obtained with the default hyperparameters indicate that both models demonstrate similar results for ‘Hispanic’ and ‘Ethnicity’ response variables. ‘Household income’ variable seems to have the poorest results, not allowing to predict the variable with adequate accuracy. Current POC suggests that the accurate prediction of demographic variable is complex task and is accompanied by certain challenges: weak relationship between demographic variables and purchase behavior, purchase location and neighborhood and its demographic characteristics, unreliable data, sparse feature set. Further investigations on feature selection and incorporation of other data sources for the training data should be considered

The Search for Invariance: Repeated Positive Testing Serves the Goals of Causal Learning

Positive testing is characteristic of exploratory behavior, yet it seems to be at odds with the aim of information seeking. After all, repeated demonstrations of one’s current hypothesis often produce the same evidence and fail to distinguish it from potential alternatives. Research on the development of scientific reasoning and adult rule learning have both documented and attempted to explain this behavior. The current chapter reviews this prior work and introduces a novel theoretical account—the Search for Invariance (SI) hypothesis—which suggests that producing multiple positive examples serves the goals of causal learning. This hypothesis draws on the interventionist framework of causal reasoning, which suggests that causal learners are concerned with the invariance of candidate hypotheses. In a probabilistic and interdependent causal world, our primary goal is to determine whether, and in what contexts, our causal hypotheses provide accurate foundations for inference and intervention—not to disconfirm their alternatives. By recognizing the central role of invariance in causal learning, the phenomenon of positive testing may be reinterpreted as a rational information-seeking strategy

Investigating the 'latent' deficit hypothesis : age at time of head injury, executive and implicit functions and behavioral insight

This study investigated the 'latent deficit' hypothesis in two groups of frontotemporal headinjured patients, those injured prior to steep morphological and corresponding functional maturational periods for frontotemporal networks (≤ age 25), and those injured >28 years. The latent deficit hypothesis proposes that early injuries produce enduring cognitive deficits manifest later in the lifespan with graver consequences for behavior than adult injuries, particularly after frontal pathology (Eslinger, Grattan, Damasio & Damasio, 1992). Implicit and executive deficits both contribute to behavioral insight after frontotemporal head injury (Barker, Andrade, Romanowski, Morton & Wasti, 2006). On the basis of morphological and behavioral data, we hypothesised that early injury would confer greater vulnerability to impairment on tasks associated with frontotemporal regions than later injury. Patients completed experimental tasks of implicit cognition, executive function measures and the DEX measure of behavioural insight (Behavioral Assessment of the Dysexecutive Syndrome: Wilson, Alderman, Burgess, Emslie, & Evans, 1996). The Early Injury group were more impaired on implicit cognition tasks compared to controls that Late Injury patients. There were no marked group differences on most executive function measures. Executive ability only contributed to behavioral awareness in the Early Injury Group. Findings showed that age at injury moderates the relationship between executive and implicit cognition and behavioral insight and that early injuries result in longstanding deficits to functions associated with frontotemporal regions partially supporting the latent deficit hypothesis

Feedback type as a moderator of the relationship between achievement goals and feedback reactions

The aim of the current study is to shed new light on the inconsistent relationship between performance-approach (PAp) goals and feedback reactions by examining feedback type as a moderator. Results of a field experiment (N = 939) using a web-based work simulation task showed that the effect of achievement-approach goals was moderated by feedback type. Relative to individuals pursuing mastery-approach goals, individuals pursuing PAp goals responded more negatively to comparative feedback but not to task-referenced feedback. In line with the hypothesized mediated moderation model, the interaction between achievement goals and feedback type also indirectly affected task performance through feedback reactions. Providing employees with feedback is a key psychological principle used in a wide range of human resource and performance management instruments (e.g., developmental assessment centres, multi-source/360 degrees feedback, training, selection, performance appraisal, management education, computer-adaptive testing, and coaching). The current study suggests that organizations need to strike a balance between encouraging learning and encouraging performance, as too much emphasis on comparative performance (both in goal inducement and in feedback style) may be detrimental to employees' reactions and rate of performance improvement

Emergence of a stable cortical map for neuroprosthetic control.

Cortical control of neuroprosthetic devices is known to require neuronal adaptations. It remains unclear whether a stable cortical representation for prosthetic function can be stored and recalled in a manner that mimics our natural recall of motor skills. Especially in light of the mixed evidence for a stationary neuron-behavior relationship in cortical motor areas, understanding this relationship during long-term neuroprosthetic control can elucidate principles of neural plasticity as well as improve prosthetic function. Here, we paired stable recordings from ensembles of primary motor cortex neurons in macaque monkeys with a constant decoder that transforms neural activity to prosthetic movements. Proficient control was closely linked to the emergence of a surprisingly stable pattern of ensemble activity, indicating that the motor cortex can consolidate a neural representation for prosthetic control in the presence of a constant decoder. The importance of such a cortical map was evident in that small perturbations to either the size of the neural ensemble or to the decoder could reversibly disrupt function. Moreover, once a cortical map became consolidated, a second map could be learned and stored. Thus, long-term use of a neuroprosthetic device is associated with the formation of a cortical map for prosthetic function that is stable across time, readily recalled, resistant to interference, and resembles a putative memory engram

Neuroimaging of Habit-based vs. Goal-directed behavior in Instrumental Learning

Addiction has been proposed to result from an overreliance on the habit-based and goal-directed controllers of behavior; however, few data exist to simultaneously support both behavioral and neuoranatomical aspects of this theory in humans. Here, we clarify the locations of the homologous structures controlling behavior in the human brain to those studied in animal models. The study included two parts. 1) The first part established in a behavioral experiment that the devaluation video in the present paradigm was able to influence instrumental behavior. Using a 3-session instrumental learning task to examine behavior, we examined 78 participants, aged 18-35. A significant difference in the change in response rate immediately before and after devaluation was found between the 2 groups viewing worms in devaluation compared to the group not viewing worms. There was a significant difference in change in liking immediately before and after devaluation between the three conditions, as well as in the change in liking, hunger, and response rate between the paired and empty bowl unpaired conditions. There was a significant correlation between snack liking pre-session 3 and response rate in session 3, as well as between pre-extinction snack liking and response rate in the start of extinction. 2) The second part of the study used the same 3-session training paradigm over 3-days, with fMRI on the third day to measure neural activity during this same instrumental learning task. Although the results are preliminary (N=10), these show that the comparable regions of the human brain are involved in goal-directed and habit-based control of behavior, with a perfect negative Spearman correlation of mean vmPFC activity at the end of training and the change in responding from immediately before to immediately after devaluation. Three of the 10 subjects were addicted smokers, which is insufficient data to determine whether they were less sensitive to reward devaluation and whether they relied more heavily on brain structures associated with habit-based controllers of behavior. However, understanding the relationship between habit-based and goal-directed controllers of behavior and their role in addiction and clarifying the human brain structures responsible for these systems can lead to the development of therapies for addiction

Neurocognitive Correlates of Treatment Response in Children with Tourette\u27s Disorder

This paper examined neurocognitive functioning and its relationship to behavior treatment response among youth with Tourette\u27s Disorder (TD) in a large randomized controlled trial. Participants diagnosed with TD completed a brief neurocognitive battery assessing inhibitory functions, working memory, and habit learning pre- and post-treatment with behavior therapy (CBIT, Comprehensive Behavioral Intervention for Tics) or psychoeducation plus supportive therapy (PST). At baseline, youth with tics and Attention Deficit Hyperactivity Disorder (ADHD) exhibited some evidence of impaired working memory and simple motor inhibition relative to youth with tics without ADHD. Additionally, a small negative association was found between antipsychotic medications and youth\u27s performance speed. Across treatment groups, greater baseline working memory and aspects of inhibitory functioning were associated with a positive treatment response; no between-group differences in neurocognitive functioning at post-treatment were identified. Within the behavior therapy group, pre-treatment neurocognitive status did not predict outcome, nor was behavior therapy associated significant change in neurocognitive functioning post-treatment. Findings suggest that co-occurring ADHD is associated with some impairments in neurocognitive functioning in youth with Tourette\u27s Disorder. While neurocognitive predictors of behavior therapy were not found, participants who received behavior therapy exhibited significantly reduced tic severity without diminished cognitive functioning