Doctor of Philosophy, Miami University, 2017, Psychology

Very little is known about the underlying neural mechanisms of individual differences in judgment and reasoning ability, and even less work has been done to investigate neural correlates of dual-processing. According to many dual-processing theories, type 2 processing in judgment and reasoning relies heavily on cognitive control. Two particular patterns of neural activity, frontal midline theta (FMT) and fronto-parietal theta coherence, have been related to cognitive control in several different paradigms. As such, they presented candidates for neural correlates of type 2 processing. Additionally, working memory capacity has been linked to FMT, fronto-parietal theta coherence, and performance on judgment and reasoning tasks. However, the relationship between these variables had not been tested in previous research. Across two experiments, working memory capacity failed to predict FMT or fronto-parietal theta coherence, but did predict more logical fallacies and semantic coherence in Experiment 2. Judgment ability was measured through the number of conjunction and disjunction fallacies committed, as well as semantic coherence, a stricter benchmark of judgment ability that measures how well participants' responses correspond to the type of probability set described in the problem In Experiment 1, FMT predicted more logical fallacies and more semantic coherence, reflecting higher levels of cognitive control. In Experiment 2, there was less fronto-parietal theta coherence in identical sets compared to other types of probability sets, which require more cognitive control, supporting the link between fronto-parietal theta coherence and cognitive control. However, neither FMT nor fronto-parietal theta coherence predicted logical fallacies or semantic coherence in Experiment 2. Together, these experiments provide preliminary evidence that FMT and fronto-parietal theta coherence are important for cognitive control in judgment and reasoning tasks, but no evidence that they ar (open full item for complete abstract)

Committee: Christopher Wolfe Dr. (Committee Chair); Robin Thomas Dr. (Committee Co-Chair); Joseph Johnson Dr. (Committee Member); Anne Farrell Dr. (Committee Member) Subjects: Cognitive Psychology

Master of Science, The Ohio State University, 1961, Graduate School

Committee: Not Provided (Other) Subjects:

BA, Oberlin College, 2022, Mathematics

Jacobi's Four Squares Theorem is a celebrated result of number theory that provides a formula for the number of ways a positive integer n can be written as a sum of four integral squares. In this paper, we prove this theorem using the theory of modular forms.

Committee: Benjamin Linowitz (Advisor) Subjects: Mathematics

Doctor of Philosophy, The Ohio State University, 2019, Communication

The aim of the present study was to examine neural correlates and mechanisms underlying the psychological mechanisms formalized in a computational model of quantum cognition, the belief-action-entanglement (BAE) model. An analysis of frequency band activity in the brain was carried out to test these mechanisms. The BAE model proposes that communication acts as a measurement that interferes with the evaluative processes prior to a decision (Busemeyer, Wang, & Lambert-Mogiliansky, 2009; Pothos & Busemeyer, 2009; Z. Wang & Busemeyer, 2016). Two key mechanisms were conceptualized and formalized in the BAE model: (1) the superposition state which arises from uncertainty and dissonance when deciding between two or more actions, and (2) the transition from a superposition state to a determinate one during the action evaluation process. These mechanisms correspond with the psychological function and timing of two frequency bands. The frontal-midline (FM) theta (3-8 Hz) indexes conflict processing, a state analogous to cognitive dissonance. Parietal alpha power indexes search and integration processes in memory which captures evolution from the superposition state to a determinate one. To test the extent communication influenced these underlying mechanisms, we employed a category-decision paradigm used in behavioral studies of the BAE model. The study manipulated communication in three ways: receiving information, self-expressing, and no communication. EEG data was collected from 32 participants. The subsequent analysis of FM theta and parietal alpha-beta frequency band activity provided modest support for the effect of communication on the proposed BAE model mechanisms. Specifically, FM theta activity offered initial evidence that communication resolves dissonance or uncertainty in the superposition state. Further, parietal alpha-beta suppression provided support for the proposition that communication modulates the evolution of the cognitive system until a decision (open full item for complete abstract)

Committee: Joyce Wang PHD (Advisor); Jason Coronel PHD (Committee Member); Richard Huskey PHD (Committee Member) Subjects: Cognitive Psychology; Communication; Neurosciences

Doctor of Philosophy (Ph.D.), Bowling Green State University, 2017, Psychology/Industrial-Organizational

As personality assessment continues to become more common in business settings, the need to understand and address faking and misrepresentation of personality in selection processes becomes extremely important. The recent advances in ideal point item response theory offer a new and more nuanced way to create personality inventories and to investigate the psychology of faking. The present study uses a within-subjects experiment to investigate how intermediate items, specifically those of the FACT taxonomy, behave under honest and faked response conditions. The effects of faking on item characteristics and respondent scores are assessed, and a technique for identifying faked responses is demonstrated.

Committee: Michael Zickar PhD (Advisor); Steve Jex PhD (Committee Member); William O'Brien PhD (Committee Member); Kate Magsamen-Conrad PhD (Other) Subjects: Psychology

Doctor of Philosophy, Miami University, 2016, Psychology

Eyeblink classical conditioning (EBC) is a widely used model of associative learning that has been utilized in studies involving both human and non-human subjects. The hippocampus is critical in acquiring the trace form of this task, and modulates performance in the delay form. Our lab has used a brain-computer interface (BCI) during EBC to control for fluctuations in the hippocampal theta rhythm, an oscillation frequently tied to cognitive processes. Training in the presence of high theta power leads to an increase in learning rate, accompanied by modulation of cellular response direction in hippocampal area CA1. However, it is unknown how additional hippocampal subregions are affected by the presence of theta oscillations. In this study, Aim I utilized tetrode recordings and a brain-computer interface (BCI) to examine response profiles of single-units in CA3. Trace EBC trials were initiated in the presence (T+) or absence (T-) of hippocampal theta. Several interneuron subtypes were identified, showing unique theta-contingent response profiles across training. Pyramidal cells were more likely to increase their firing early in training in the T+ condition than the T- condition; however, that pattern was reversed during the late learning phase. Importantly, no difference was seen in the magnitude of response between T+ and T- pyramidals, suggesting theta is involved in the recruitment of cells rather than simply modulating firing rate. In Aim II, units were recorded during both T+ and T- triggered trials following asymptotic behavioral performance. Previous research has shown two classes of theta-responsive cells: Theta-On (increase firing during theta) and Theta-Off (increase in the absence of theta). Regardless of triggering theta-state, Theta-On cells were more likely to increase their firing in animals initially trained in T+ conditions, while Theta-Off cells increased at a higher rate in T- animals. These findings indicate that during acquisition, theta-state re (open full item for complete abstract)

Committee: Stephen Berry Ph.D. (Committee Chair); Jennifer Quinn Ph.D. (Committee Member); Barbara Oswald Ph.D. (Committee Member); Kathleen Killian Ph.D. (Committee Member) Subjects: Behavioral Sciences; Neurosciences; Psychobiology; Psychology

Doctor of Philosophy, The Ohio State University, 2014, Psychology

The set of experiments within this dissertation were designed to characterize neural oscillations within in vivo local field potentials recorded simultaneously from the hippocampus, medial prefrontal cortex, and anterior cingulate cortex of rats while performing a goal maintenance operant working memory task. Detailed behavioral and neurophysiological analyses were performed during the course of learning the task and after pharmacological challenge with acute ethanol. The primary goal was to enhance understanding of how the theta and gamma rhythms interact in the hippocampal-frontal cortex circuit to mediate successful and unsuccessful working memory performance. First, detailed behavioral analyses were performed on the operant variable delayed non-match to position goal maintenance working memory task. Most animals were able to learn the task over time. The task had sufficient simplicity and complexity to avoid most floor and ceiling effects. Results indicate that as delay increased, performance generally decreased thus validating this task as assessing working memory function. Next, neurophysiological analyses were performed on animals that eventually became fast or slow learners of the task to see if there were any early indicators predictive of good performance. Animals in the fast learning group had higher baseline theta in the medial prefrontal cortex and anterior cingulate cortex than animals in the slow group. The medial prefrontal cortex also elicited stronger stimulus-evoked potentials than the anterior cingulate cortex. Both the medial prefrontal cortex and the anterior cingulate were more highly correlated with the ventral hippocampus in the early sessions compared to the late recording sessions, suggesting that the role of the hippocampus in the delayed non-match to position operant task may change over time. Next, performance was disrupted by administering an acute pharmacological challenge with low to moderate doses of ethanol. E (open full item for complete abstract)

Committee: Bennet Givens Ph.D (Advisor); John Bruno Ph.D. (Committee Member); Derick Lindquist Ph.D. (Committee Member) Subjects: Neurosciences; Psychobiology; Psychology

Doctor of Philosophy, Miami University, 2014, Psychology

The cerebellum is required for all forms of eyeblink classical conditioning (EBCC). The hippocampus also becomes essential as the time constraints of cerebellar plasticity are exceeded, such as in the case of trace EBCC. Despite reports of modulations of learning related unit activity between these two areas during acquisition, no direct connections between dorsal hippocampus and cerebellum exist and the relationship between the cerebellum and hippocampus during this task remains a major unanswered question for neurobiological theories of EBCC. Previous research from our lab has used a brain-computer interface (BCI) to control naturally-occurring extremes of hippocampal theta state between groups during training trials and has demonstrated that hippocampal theta-contingent trial presentation of trace EBCC corresponds to enhanced learning rate and a concomitant synchronization of hippocampus and cerebellar regions (Hoffmann & Berry, 2009). In light of these findings, questions on the nature of cerebellar theta and the degree of independence of theta oscillations in these two structures have surfaced. Using the well-articulated model of mammalian associative learning, trace EBCC, two experiments are presented that address the impact of synchronized versus desynchronized hippocampal-cerebellar oscillations during different phases of the learning process. Experiment I compares theta-based coordination of hippocampus and cerebellum during cerebellar theta-contingent and hippocampal theta-contingent trace EBCC. Cerebellar non-theta is accompanied by significantly larger learning deficits late in training while hippocampal triggering effects are strongest during early learning. The location and timing of theta as well as hippocampo-cerebellar synchrony in LFPs supports an early role for hippocampus and a later role for cerebellar theta in coordinating the distributed system. Experiment II assesses the relationship of cerebellar theta to extinction of trace EBCC (open full item for complete abstract)

Committee: Stephen Berry Ph.D. (Advisor); Jennifer Quinn Ph.D. (Committee Member); Dragana Ivkovic-Claflin Ph.D. (Committee Member); Barbara Oswald Ph.D. (Committee Member); Kathleen Killian Ph.D. (Committee Member) Subjects: Neurobiology; Neurosciences

Master of Arts, The Ohio State University, 2011, Psychology

In the set of experiments within this document, the effects of acute ethanol intoxication on memory encoding, retrieval, and the theta rhythm were explored. We adapted a common working memory operant task (DNMTP) into a serial reversal paradigm that assesses both short-term and long-term processes of encoding and retrieval of memory. Using this task, we found that animals are able to reliably learn match and non-match to position rules, and are readily able to switch between the two rule conditions. The single switch paradigm produced a dose-dependent impairment in memory encoding for task rules demonstrated by decreased overall accuracy for the post-switch session. The double switch paradigm showed that ethanol produced a slight improvement in the second switch performance relative to controls, suggesting less interference due to a failure to encode the new contingency on the intervening first switch day. These results support the hypothesis that ethanol disrupts memory encoding for task rules on switch days, and that these effects are not due to a general cognitive impairment. By recording neurophysiological activity while the animals engaged in a rule-switch session, we were able to gain insight into the effects of alcohol on the rapid encoding and retrieval processes associated with the sample and choice phases of the task respectively. In awake, behaving rats we observed local field potentials that showed high activity in the theta band frequency (4-10 Hz). The overall power of the theta rhythm was reduced in a dose-dependent manner. In the encoding phase of the task when waveform averages were gated to the light onset, we found clear and consistent synchrony across anatomical recording sites including the entorhinal cortex, the dentate gyrus of the hippocampal formation, and the anterior cingulate region of the prefrontal cortex. In the present studies, we did not find conclusive evidence in support of a theta reset phenomenon or stronger synchronization betwe (open full item for complete abstract)

Committee: Ben Givens PhD (Advisor); John Bruno PhD (Committee Member); Derick Lindquist PhD (Committee Member) Subjects: Neurobiology; Psychology

Doctor of Philosophy, The Ohio State University, 2006, Atmospheric Sciences

The upper ocean significantly influences tropical cyclone structure and intensity. These effects, however, are not well understood mostly due to a lack of oceanic and atmospheric boundary layer observations within the inner-core region. This study relates ocean-atmosphere energy exchange processes to mid-to-upper tropospheric latent heating using mesoscale inner-core convective burst events. A global survey of convective burst events in tropical cyclones from the year 1999 – 2001 was constructed. This study shows that 80% of tropical cyclones have at least one convective burst event and that convective burst events usually occur during the intensification phase of the storm life cycle. Latent and sensible heat flux estimates and a measure of upper-ocean energy utilization were calculated for the inner-core (<.5° radius) and the near-core (.5° - 1° radius). This study found that tropical cyclones generally utilize only about 8% of the total enthalpy flux available from the ocean/atmosphere boundary layer. Storms with convective bursts utilize more energy from the ocean (11%) than storms with no convective burst (2%). Sea-air fluxes are greatly enhanced (doubled) during convective burst time periods. These along-track ocean-atmosphere analyses was compared to vertical profiles of atmospheric latent heating calculated using a combined active and passive TRMM PR and TMI retrieval algorithm. Results show strong positive space and time correlations between ocean-air fluxes and mid-upper tropospheric latent heating. Additionally, the 30 storms analyzed were categorized by the presence or absence of convective burst events during the storm lifecycle. Composite atmospheric latent heating profiles constructed for each group show a two-fold release in energy for the storms with convective burst events compared to storms with no convective burst event. Finally, seven case studies are presented which attempt to resolve the upscale energy cascade of the tropical cyclone with a co (open full item for complete abstract)

Committee: Jay Hobgood (Advisor) Subjects:

Master of Science (MS), Ohio University, 1981, Electrical Engineering & Computer Science (Engineering and Technology)

Design and construction of a scanning VOR controller and audio processor

Committee: Richard McFarland (Advisor) Subjects:

Master of Arts, Miami University, 2009, Psychology

The hippocampus and cerebellum are critically involved in trace eyeblink classical conditioning (EBCC). The mechanisms underlying the hippocampal-cerebellar interaction during this task are not well understood, although hippocampal theta (3-7 Hz) oscillations are known to reflect a favorable state for EBCC. Two groups of rabbits received trace EBCC in which a brain-computer interface administered trials in either the explicit presence or absence of naturally occurring hippocampal theta. A high percentage of robust theta led to a striking enhancement of learning accompanied by rhythmic theta-band (6-7 Hz) oscillations in the interpositus nucleus (IPN) and cerebellar cortex that were time-locked both to hippocampal rhythms and sensory stimuli during training. Rhythmic activity was absent in the cerebellum of the non-theta group. These data strongly suggest a beneficial impact of theta-based coordination of hippocampus and cerebellum and, importantly, demonstrate that hippocampal theta oscillations can be used to regulate the functional properties of the cerebellum.

Committee: Stephen Berry PhD (Advisor); Jennifer Quinn PhD (Committee Member); Dragana Ivkovich Claflin PhD (Committee Member) Subjects: Psychobiology

Doctor of Philosophy, Miami University, 2008, Psychology

Rabbit eyeblink classical conditioning (EBCC) is a task widely used to understand the neurobiological correlates of associative learning and memory. The hippocampus has proven to be an important structure in acquiring the association between the conditioning stimuli and the development of conditioned responses. This study used a brain-computer interface to trigger conditioning trials in the presence (T+) or absence (T-) of a frequency component of the hippocampal field potential historically related to sensory processing and attention, termed theta. The presence of theta has been shown to facilitate learning in this task as well as accelerate learning related unit responses in the hippocampus, but the precise nature of its beneficial effect in hippocampal neurophysiology has yet to be determined. In this study, tetrodes were lowered into the dorsal hippocampus of four groups of rabbits including those who received paired or unpaired conditioning stimuli in both T+ and T- theta conditions. Specialized signal processing software compared the extracted data streams from each wire of the tetrode to separate the waveforms into single neuron responses. Each sorted neuron was then categorized according to its firing properties as pyramidal cells or one of the known types of interneurons that exist in the hippocampus. The individual units were analyzed for their relation to the pretrial period as well as for how they responded to the conditioning stimuli. Interneurons were highly correlated with hippocampal state used to trigger the trials, supporting the existence of interneurons that systematically vary with the ongoing theta activity. Interneuron responses to the conditioning stimuli were generally dependent on hippocampal state, demonstrating excitatory responses in T+ groups and suppression in T- groups. Pyramidal cells that demonstrated suppression to the conditioning stimuli were also more common in T- groups, while excitatory pyramidal cells were more related to ass (open full item for complete abstract)

Committee: Stephen Berry PhD (Advisor); Allan Pantle PhD (Committee Member); Dragana Ivkovich Claflin PhD (Committee Member); Kathleen Killian PhD (Committee Member) Subjects: Behaviorial Sciences; Physiological Psychology; Psychobiology; Psychology

Master of Arts, Miami University, 2005, Psychology

This project manipulated the administration of nictitating membrane conditioning trials as a function of discrete hippocampal states. A brain-computer interface triggered trial presentation during the explicit presence (T+) or absence (T-) of 3-7 Hz theta. Theta-triggering has proven to be an effective manipulation to facilitate behavioral learning and to accelerate hippocampal plasticity early in training. Hippocampal evoked potentials were time-locked to both conditioned and unconditioned stimuli. These responses reset on-going theta in the T+ group or elicited coherent post-stimulus theta in the T- group. Simultaneous recordings from two areas in prefrontal cortex revealed hippocampal state-modulated excitatory responses. These findings are the first attempt to evaluate the effect of hippocampal state on other forebrain structures and support theta as an important regulator of both hippocampal and prefrontal involvement during this task. These data are consistent with a hypothesized role of theta to coordinate distributed networks with increasing complexity of classical conditioning.

Committee: Stephen Berry (Advisor) Subjects: Psychology, Psychobiology

Master of Arts, Miami University, 2013, Psychology

Hippocampal interneurons are a heterogeneous group with identifiable subtypes. The present study utilized tetrode recordings and a brain-computer interface (BCI) to examine response profiles of five interneuron types (axo-axonic, basket, bistratified, cholecystokinin-expressing, and oriens-lacunosum-moleculare cells) during trace eyeblink conditioning in the rabbit. The BCI initiated trials in the presence (T+) or absence (T-) of hippocampal theta, a methodology previously shown to affect learning rate. In various trial epochs, T+ axo-axonic and basket cells showed greater responses than those in T-, while T- oriens-lacunosum-moleculare cells showed greater responses than in T+. Such response profiles are consistent with models proposing a role for theta in storage vs. retrieval functions of the hippocampus. These data suggest theta modulation of distinct responses of interneuron subtypes, and support the idea that the naturally occurring theta rhythm can affect information processing by the hippocampus in ways that cause a significant improvement in behavioral learning rate.

Committee: Stephen Berry PhD (Committee Chair); Barbara Oswald PhD (Committee Member); Jennifer Quinn PhD (Committee Member) Subjects: Neurobiology; Psychobiology