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- Title
- Dynamics of human sensorimotor coordination: From behavior to brain activity.
- Creator
- Chen, Yanqing, Florida Atlantic University, Ding, Mingzhou, Kelso, J. A. Scott
- Abstract/Description
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The dynamics of human sensorimotor coordination are studied at behavioral and neural levels through temporal synchronization and syncopation tasks. In experiment 1, subjects synchronized their finger movements (in-phase) with a metronome at 2.0Hz and 1.25Hz for 1200 cycles. Fluctuations of timing errors were analyzed through correlation, power spectrum analyses and Maximum Likelihood Estimation (MLE). Results indicated that the synchronization error time series was characterized by a 1/falpha...
Show moreThe dynamics of human sensorimotor coordination are studied at behavioral and neural levels through temporal synchronization and syncopation tasks. In experiment 1, subjects synchronized their finger movements (in-phase) with a metronome at 2.0Hz and 1.25Hz for 1200 cycles. Fluctuations of timing errors were analyzed through correlation, power spectrum analyses and Maximum Likelihood Estimation (MLE). Results indicated that the synchronization error time series was characterized by a 1/falpha type of long memory process with alpha = 0.5. Previous timing models based upon motor program or simple "central clock" ideas were reviewed to show that they could not explain such long range correlations in the synchronization task. To explore the possible cognitive origins of long range correlation, experiment 2 required subjects to synchronize (on the beat) or syncopate (off the beat) to a metronome at 1Hz using different cognitive strategies. Timing fluctuations were again found to be 1/f alpha type, with alpha = 0.5 in synchronization and alpha = 0.8 in syncopation. When subjects employed a synchronization strategy to successfully syncopate, timing fluctuations shifted toward 1/f 0.5 type. This experiment indicated that the scaling exponent in timing fluctuations was related to task requirements and specific coordination strategies. Further, they suggest that the sources of such long memory originated from higher level cognitive processing in the human brain. Experiment 3 analyzed magnetoencephalography (MEG) data associated with synchronization and syncopation tasks. Brain oscillations at alpha (8--14Hz), beta (15--20Hz) and gamma (35--40Hz) frequency ranges were shown to correlate with different aspects of the coordination behavior. Specifically, through power and coherence analyses, alpha activity was linked to sensorimotor integration and "binding", beta activity was related to task requirements (synchronization or syncopation), and gamma activity was related to movement kinematics (trajectory). These results supported the idea that the 1/f alpha type of timing fluctuations originated from collective neural activities in the brain acting on multiple time scales.
Show less - Date Issued
- 2000
- PURL
- http://purl.flvc.org/fcla/dt/12649
- Subject Headings
- Sensorimotor integration, Cognitive neuroscience
- Format
- Document (PDF)
- Title
- Neural substrates of movement and music: An fMRI approach.
- Creator
- Nair, Dinesh G., Florida Atlantic University, Charles E. Schmidt College of Science, Center for Complex Systems and Brain Sciences
- Abstract/Description
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In this dissertation, we examined the neural correlates of motor coordination and music perception using a set of four fMRI experiments. The neural correlates of goal-directed action were examined in a group of healthy adults in experiment I using execution and imagery of a unimanual and a bimanual finger-sequencing task. Similar neural networks were engaged for execution and imagination of movement sequences. Interestingly, we also found that the sensorimotor cortical and cerebellar areas...
Show moreIn this dissertation, we examined the neural correlates of motor coordination and music perception using a set of four fMRI experiments. The neural correlates of goal-directed action were examined in a group of healthy adults in experiment I using execution and imagery of a unimanual and a bimanual finger-sequencing task. Similar neural networks were engaged for execution and imagination of movement sequences. Interestingly, we also found that the sensorimotor cortical and cerebellar areas are functionally decoupled from the task network when people imagine but do not actually execute sequential actions. In experiment 2, we used the same finger-sequencing paradigm to study recovery of function during recovery from stroke. It was observed that the wide spread neural activity during the initial session became more localized during the last session. In addition, using imagery tasks, we showed that hemiplegic patients retained the ability to activate neural pathways that are normally involved in executing goal-directed action sequences, despite the loss of ability to actually execute movements. In experiment 3, we examined brain activity when musicians and non-musicians listened to expressive and mechanical versions of a musical piece. The expressive performance activated the limbic areas more than the mechanical version in both groups of subjects suggesting perception of affect. The pattern of neural activity was also dictated by their experience and familiarity with the piece of music. In addition, we found activation of language related areas when musicians listened to the expressive version suggesting shared neural resources for language and music. The neural basis of sensorimotor coordination and timing in Parkinson's disease was investigated in the last experiment, using a synchronization-syncopation task and the continuation paradigm. Different neural areas subserved timing during the two different modes of coordination. However, these differences persisted during their respective continuation phases. In order to compensate for the functional deficiency in Parkinson's disease, patients recruited functionally segregated circuits that connect the striatum and association areas of the parietal, premotor and prefrontal cortices.
Show less - Date Issued
- 2004
- PURL
- http://purl.flvc.org/fcla/dt/12082
- Subject Headings
- Biology, Neuroscience, Psychology, Cognitive
- Format
- Document (PDF)
- Title
- Devising a novel protocol to study 5-hydroxymethylcytosine's role in the consolidation of a methamphatamine [sic] associated contextual memory.
- Creator
- Odom, John David., Harriet L. Wilkes Honors College
- Abstract/Description
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DNA methylation, the addition of a methyl group to the 5' position of DNA cytosines (5mC), is generally associated with transcriptional repression during early embryo formation ; however, in the adult brain, it is dynamically regulated and plays an important role in the formation and maintenance of memory. Very recently, it has been hypothesized that DNA hydroxymethylation, the addition of a hydroxyl group to methylated cytosines (5mC), serves as an intermediate in the DNA demethylation...
Show moreDNA methylation, the addition of a methyl group to the 5' position of DNA cytosines (5mC), is generally associated with transcriptional repression during early embryo formation ; however, in the adult brain, it is dynamically regulated and plays an important role in the formation and maintenance of memory. Very recently, it has been hypothesized that DNA hydroxymethylation, the addition of a hydroxyl group to methylated cytosines (5mC), serves as an intermediate in the DNA demethylation pathway. GIven its recent discovery, the role of DNA hydroxymethylation in memory has not yet been explored. In this study, we developed an immunofluorescent triple labeling protocol in order to begin examining the involvement of 5mC and 5hmC in neurons activated by consolidation of a contextual memory associated with methamphetamine in the brain's reward center, the nucleus accumbens.
Show less - Date Issued
- 2012
- PURL
- http://purl.flvc.org/FAU/3359318
- Subject Headings
- Memory, Physiological aspects, Cognitive neuroscience, DNA, Methylation
- Format
- Document (PDF)
- Title
- Perception of facial affect: A functional magnetic resonance imaging study of adolescents and adults with and without nonverbal learning disabilities.
- Creator
- Vallabha, Taube Lubart, Florida Atlantic University, Charles E. Schmidt College of Science, Center for Complex Systems and Brain Sciences
- Abstract/Description
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Individuals with nonverbal learning disabilities (NLD) have an impaired ability to interpret facial expressions of emotion (FEE), the consequences of which can include progressively debilitating socioemotional disturbances. Thus, it is important to determine how the neuroanatomical structures underlying the perception of FEE in people with NLD differ from the normal population. To this end, functional magnetic resonance imaging was used to compare brain activation patterns in male and female...
Show moreIndividuals with nonverbal learning disabilities (NLD) have an impaired ability to interpret facial expressions of emotion (FEE), the consequences of which can include progressively debilitating socioemotional disturbances. Thus, it is important to determine how the neuroanatomical structures underlying the perception of FEE in people with NLD differ from the normal population. To this end, functional magnetic resonance imaging was used to compare brain activation patterns in male and female adolescent subjects and male adult subjects with and without NLD. The subjects were presented with FEE at low and high intensities while they performed a gender decision task. Subjects with NLD displayed less activation in limbic areas responsible for processing emotion in the normal population. The NLD subjects exhibited more activity than controls in the orbital gyrus, inferior, middle and superior frontal gyri, fusiform and superior temporal gyri, insula, striatum and inferior and superior parietal lobules. Several of these structures participate in language function: as individuals with NLD have superior verbal abilities, it is probable that this population relies on their linguistic strengths to compensate for their nonverbal weaknesses whilst processing FEE. Additionally, because of an impaired capacity for attention to and discrimination of visual details, the NLD subjects showed more active responses for low intensity FEE in comparison to controls. This may have led to a failure of regions such as the middle and superior frontal and superior temporal gyri to habituate or sensitize appropriately to emotionally salient visual stimuli. In comparison with the normal population, people with NLD utilize different neural structures when processing FEE, in accordance with the strengths and deficits associated with the NLD syndrome.
Show less - Date Issued
- 2003
- PURL
- http://purl.flvc.org/fau/fd/FADT12051
- Subject Headings
- Biology, Neuroscience, Education, Special, Psychology, Cognitive
- Format
- Document (PDF)
- Title
- Memory deficits for faces and names in Alzheimer's disease: Investigation with a faces-names Stroop-like task.
- Creator
- Taft, Janna Renee., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Psychology
- Abstract/Description
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A prominent deficit in Alzheimer's disease (AD) is a difficulty in recognizing and naming people. Unfamiliar and famous face recognition tasks are sparse in the neuropsychology literature. It was hypothesized that: a deficit in recognition of faces would be found for AD patients, the semantic mismatch condition would result in the longest response latency and least accurate naming, and semantic cues would not facilitate naming for the AD group. Accuracy and reaction time from ten mild AD...
Show moreA prominent deficit in Alzheimer's disease (AD) is a difficulty in recognizing and naming people. Unfamiliar and famous face recognition tasks are sparse in the neuropsychology literature. It was hypothesized that: a deficit in recognition of faces would be found for AD patients, the semantic mismatch condition would result in the longest response latency and least accurate naming, and semantic cues would not facilitate naming for the AD group. Accuracy and reaction time from ten mild AD patients diagnosed by NINCDS-ADRDA criteria and 10 normal controls (matched age, 66--82 years, education & ethnicity) were tested via unfamiliar and famous faces recognition memory tests and famous faces naming tasks with and without semantic interference. Both subject groups were more accurate on the famous face recognition rather than memory for unfamiliar faces, with significant group differences. The Stroop-like face naming task performance was characterized by an increased interference effect, semantic face-name mismatches produced the longest response delays, and less accurate face naming particularly in the AD group. The semantic cues resulted in a decrease in naming accuracy for the AD patients, which may be indicative of their name retrieval deficit. Consistent with existing face-name models, these findings suggest that the deficit in AD is related to semantic naming rather than the perceptual component of face recognition. Furthermore, the ability to correctly name faces even in the presence of interference may prove to be a diagnostic tool that is sensitive to face naming deficits characteristic in cases of brain damage.
Show less - Date Issued
- 2003
- PURL
- http://purl.flvc.org/fau/fd/FADT12061
- Subject Headings
- Biology, Neuroscience, Psychology, Clinical, Psychology, Cognitive
- Format
- Document (PDF)
- Title
- Functional roles of L1-Cam/Neuroglian in the nervous system of Drosophila Melanogaster.
- Creator
- Kudumala, Sirisha, Godenschwege, Tanja A., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Neuronal cell adhesion molecules of L1 family play a critical role in proper nervous system development. Various mutations on human L1-CAM that lead to severe neurodevelopmental disorders like retardation, spasticity etc. termed under L1 syndrome. The vertebrr their roles in axon pathfinding, neurite extension and cell migration, howeverate L1CAM and its homolog in Drosophila, neuroglian (nrg) have been well studied fo, much less is known about the mechanisms by which they fine tune synaptic...
Show moreNeuronal cell adhesion molecules of L1 family play a critical role in proper nervous system development. Various mutations on human L1-CAM that lead to severe neurodevelopmental disorders like retardation, spasticity etc. termed under L1 syndrome. The vertebrr their roles in axon pathfinding, neurite extension and cell migration, howeverate L1CAM and its homolog in Drosophila, neuroglian (nrg) have been well studied fo, much less is known about the mechanisms by which they fine tune synaptic connectivity to control the development and maintenance of synaptic connections within neuronal circuits. Here we characterized the essential role of nrg in regulating synaptic structure and function in vivo in a well characterized Drosophila central synapse model neuron, the Giant Fiber (GF) system. Previous studies from our lab revealed that the phosphorylation status of the tyrosine in the Ankyrin binding FIGQY motif in the intracellular domain of Nrg iscrucial for synapse formation of the GF to Tergo-Trochanteral Motor neuron (TTMn) synapse in the GF circuit. The present work provided us with novel insights into the role of Nrg-Ank interaction in regulating Nrg function during synapse formation and maintenance. By utilizing a sophisticated Pacman based genomic rescue strategy we have shown that dynamic regulation of the Neuroglian–Ankyrin interaction is required to coordinate transsynaptic development in the GF–TTMn synapse. In contrast, the strength of Ankyrin binding directly controls the balance between synapse formation and maintenance at the NMJ. Human L1 pathological mutations affect different biological processes distinctively and thus their proper characterization in vivo is essential to understand L1CAM function. By utilizing nrg14;P[nrg180ΔFIGQY] mutants that have exclusive synaptic defects and the previously characterized nrg849 allele that affected both GF guidance and synaptic function, we were able to analyze pathological L1CAM missense mutations with respect to their effects on guidance and synapse formation in vivo. We found that the human pathological H210Q, R184Q and Y1070C, but not the E309K and L120V L1CAM mutations affect outside-in signaling via the FIGQY Ankyrin binding domain which is required for synapse formation and not for axon guidance while L1CAM homophilic binding and signaling via the ERM motif is essential for axon guidance in Drosophila.
Show less - Date Issued
- 2014
- PURL
- http://purl.flvc.org/fau/fd/FA00004131, http://purl.flvc.org/fau/fd/FA00004131
- Subject Headings
- Cell adhesion molecules, Cellular signal transduction, Cognitive neuroscience, Cognitive neuroscience, Drosophila melanogaster, Molecular neurobiology
- Format
- Document (PDF)
- Title
- Functional consequences of top-down anticipatory modulation of primary visual cortex.
- Creator
- Richter, Craig G., Charles E. Schmidt College of Science, Center for Complex Systems and Brain Sciences
- Abstract/Description
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It is well established that anticipation of the arrival of an expected stimulus is accompanied by rich ongoing oscillatory neurodynamics, which span and link large areas of cortex. An intriguing possibility is that these dynamic interactions may convey knowledge that is embodied by large-scale neurocognitive networks from higher level regions of multi-model cortex to lower level primary sensory areas. In the current study, using autoregressive spectral analysis, we establish that during the...
Show moreIt is well established that anticipation of the arrival of an expected stimulus is accompanied by rich ongoing oscillatory neurodynamics, which span and link large areas of cortex. An intriguing possibility is that these dynamic interactions may convey knowledge that is embodied by large-scale neurocognitive networks from higher level regions of multi-model cortex to lower level primary sensory areas. In the current study, using autoregressive spectral analysis, we establish that during the anticipatory phase of a visual discrimination task there are rich patterns of coherent interaction between various levels of the ventral visual hierarchy across the frequency spectrum of 8 - 90 Hz. Using spectral Granger causality we determined that a subset of these interactions carry beta frequency (14 - 30 Hz) top-down influences from higher level visual regions V4 and TEO to primary visual cortex. We investigated the functional significance of these top-down interactions by correlating the magnitude of the anticipatory signals with the amplitude of the visual evoked potential that was elicited by stimulus processing. We found that in one third of the extrastriate-striate pairs, tested in three monkeys, the amplitude of the visual evoked response is well predicted by the magnitude of pre-stimulus coherent top-down anticipatory influences. To investigate the dynamics of the coherent and topdown Granger causal interactions, we analyzed the relationship between coherence and top-down Granger causality with stimulus onset asynchrony. This analysis revealed that in an abundance of cases the magnitudes of the coherent interactions and top-down directional influences scaled with the length of time that had elapsed before stimulus onset., Together these results reveal a complex network of coherent and top-down directional interactions that predict the amplitude of early components of the visual evoked potential in primary visual cortex and vary in strength on the basis of the length of the stimulus onset.
Show less - Date Issued
- 2009
- PURL
- http://purl.flvc.org/FAU/369200
- Subject Headings
- Cognitive neuroscience, Brain mapping, Visual perception, Testing, Intersensory effects
- Format
- Document (PDF)
- Title
- Hominin endocast topography: an analysis using geographic information systems.
- Creator
- Boas, Melissa., Dorothy F. Schmidt College of Arts and Letters, Department of Anthropology
- Abstract/Description
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This study examined the topography of prefrontal molds of human endocasts using three-dimensional laser scanning and geographic information systems (GIS) in order to carry out intra-species comparisons. Overall brain topography can indicate when major reorganizational shifts in brain structure happened in our evolutionalry history, and these shifts may indicate major shifts in cognition and behavior. Endocasts are one of the sole sources of information about extinct hominin brains ; they...
Show moreThis study examined the topography of prefrontal molds of human endocasts using three-dimensional laser scanning and geographic information systems (GIS) in order to carry out intra-species comparisons. Overall brain topography can indicate when major reorganizational shifts in brain structure happened in our evolutionalry history, and these shifts may indicate major shifts in cognition and behavior. Endocasts are one of the sole sources of information about extinct hominin brains ; they reproduce details of the brain's external morphology. Analysis of endocast morphology has never been done using GIS methodology. The use of GIS helps to overcome previous obstacles in regards to endocast analysis. Since this methodology is new, this research focuses on only one species, Homo sapiens and the area of focus is narrowed to the frontal lobe, specifically Broca's cap. This area is associated with speech in humans and is therefore of evolutionary significance. The variability in lateralization of this feature was quantified.
Show less - Date Issued
- 2012
- PURL
- http://purl.flvc.org/FAU/3358286
- Subject Headings
- Human evolution, Brain mapping, Cognitive neuroscience, Geographic information systems
- Format
- Document (PDF)
- Title
- Memory Narrowing and Thematic Arousal: The Effect of Negative Emotion on Memory for Event Details.
- Creator
- Curtayne, Eileen, Kersten, Alan, Florida Atlantic University
- Abstract/Description
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Laney, Campbell, Heuer, and Reisberg (2004) proposed that the preferential recall of central relative to peripheral information in a negative event (known as "memory narrowing") is the product of presenting participants with a visually arousing attention magnet -- not negative emotion, as the Easterbrook ( 1959) hypothesis suggests. Laney et al. used conceptually meaningful (or thematically arousing) events to stimulate an emotional response in participants instead of visual arousal and found...
Show moreLaney, Campbell, Heuer, and Reisberg (2004) proposed that the preferential recall of central relative to peripheral information in a negative event (known as "memory narrowing") is the product of presenting participants with a visually arousing attention magnet -- not negative emotion, as the Easterbrook ( 1959) hypothesis suggests. Laney et al. used conceptually meaningful (or thematically arousing) events to stimulate an emotional response in participants instead of visual arousal and found evidence that negative arousal improves memory for all categories of details. The current study tested Laney et al. 's theory that a visually arousing stimulus, rather than negative arousal, is responsible for memory nan·owing as well as their position that negative arousal benefits recall of both central and peripheral information. Support was found for both assertions of Laney et al. The presence of a visually salient and emotionally provoking detail produced an effect similar to the traditional memory narrowing pattem and exposure to the negative thematic climax resulted in improved memory performance for all the detail categories. However, this latter effect was observed only for the female participants. No evidence was found to support the Easterbrook hypothesis.
Show less - Date Issued
- 2007
- PURL
- http://purl.flvc.org/fau/fd/FA00000850
- Subject Headings
- Eyewitness identification--Psychological aspects, Memory--Research, Cognitive neuroscience
- Format
- Document (PDF)
- Title
- A Hebbian characterization of mismatch negativity.
- Creator
- Starratt, Gerene K., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Psychology
- Abstract/Description
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Mismatch Negativity (MMN) is a component of the event-related potential (ERP) that is associated with the detection of novel stimuli in one's environment. Naatanen has suggested that a neural template theory provides the best explanation of the mechanism that underlies this psychophysiological phenomenon. The purpose of the present project was to propose that a Hebbian model of cell-assemblies (Hebb, 1949) provides a plausible competing theory of MMN. A Hebbian model is consistent with the...
Show moreMismatch Negativity (MMN) is a component of the event-related potential (ERP) that is associated with the detection of novel stimuli in one's environment. Naatanen has suggested that a neural template theory provides the best explanation of the mechanism that underlies this psychophysiological phenomenon. The purpose of the present project was to propose that a Hebbian model of cell-assemblies (Hebb, 1949) provides a plausible competing theory of MMN. A Hebbian model is consistent with the evidence provided by imaging studies that demonstrate increased neural efficiency in learning cognitive (as opposed to skilled motor) tasks and with recent animal studies in an analogous model. This model suggests three hypotheses which were addressed by the present study. First, it is proposed that the method that is traditionally used to calculate MMN may not be the ideal. Specifically, it is proposed that the baseline measure used in the calculation does not yield optimal MMN data and the present experiment investigated a new method of gathering baseline data. Second, it was hypothesized that an investigation of sequence effects related to standard and deviant stimuli in an oddball paradigm would provide further support for a Hebbian reinterpretation of MMN. Finally, the argument is made that a Hebbian model of MMN garners additional support in terms of parsimony and ecological validity in addition to being consistent with our current understanding of the physiological underpinnings of learning phenomena. Results indicate that the new method of calculating MMN does, indeed, provide a more robust measure of MMN. Furthermore, sequence effects were demonstrated for both the standard and deviant stimuli, however the sequence effects observed in standard stimuli were not in the expected direction. Both practical and theoretical implications are discussed.
Show less - Date Issued
- 1998
- PURL
- http://purl.flvc.org/fcla/dt/12561
- Subject Headings
- Biology, Neuroscience, Psychology, Psychometrics, Psychology, Cognitive, Psychology, Physiological
- Format
- Document (PDF)
- Title
- The Role of Dorsal Anterior Cingulate Cortex in the Motor Control.
- Creator
- Asemi, Avisa, Bressler, Steven L., Florida Atlantic University, Charles E. Schmidt College of Science, Center for Complex Systems and Brain Sciences
- Abstract/Description
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We sought to better understand human motor control by investigating functional interactions between the Supplementary Motor Area (SMA), dorsal Anterior Cingulate Cortex (dACC), and primary motor cortex (M1) in healthy adolescent participants performing visually coordinated unimanual finger-movement and n-back working memory tasks. We discovered modulation of the SMA by the dACC by analysis of fMRI BOLD time series recorded from the three ROIs (SMA, dACC, and M1) in each participant. Two...
Show moreWe sought to better understand human motor control by investigating functional interactions between the Supplementary Motor Area (SMA), dorsal Anterior Cingulate Cortex (dACC), and primary motor cortex (M1) in healthy adolescent participants performing visually coordinated unimanual finger-movement and n-back working memory tasks. We discovered modulation of the SMA by the dACC by analysis of fMRI BOLD time series recorded from the three ROIs (SMA, dACC, and M1) in each participant. Two measures of functional interaction were used: undirected functional connectivity was measured using the Pearson product-moment correlation coefficient (PMCC), and directed functional connectivity was measured from linear autoregressive (AR) models. In the first project, task-specific modulation of the SMA by the dACC was discovered while subjects performed a coordinated unimanual finger-movement task, in which the finger movement was synchronized with an exogenous visual stimulus. In the second project, modulation of the SMA by the dACC was found to be significantly greater in the finger coordination task than in an n-back working memory, in which the same finger movement signified a motor response indicating a 0-back or 2-back working memory match. We thus demonstrated in the first study that the dACC sends task-specific directed signals to the supplementary motor area, suggesting a role for the dACC in top-down motor control. Finally, the second study revealed that these signals were significantly greater in the coordinated motor task than in the n-back working memory task, suggesting that the modulation of the SMA by the dACC was associated with sustained, continuous motor production and/or motor expectation, rather than with the motor movement itself.
Show less - Date Issued
- 2015
- PURL
- http://purl.flvc.org/fau/fd/FA00004478
- Subject Headings
- Brain mapping, Cerebral cortex -- Anatomy, Cognitive neuroscience, Computational neuroscience, Movement sequences, Perceptual motor learning, Sensorimotor integration
- Format
- Document (PDF)
- Title
- Electroencephalography in children with autism.
- Creator
- Lucas, Nikola N., Jones, Nancy Aaron, Charles E. Schmidt College of Science, Department of Psychology
- Abstract/Description
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Autism is a neurodevelopmental disorder that is characterized by deficits involving social interaction, communication, and perception. Although there is much research that has examined functional neural connectivity in individuals with autism, few have conducted these studies in very young children while awake across EEG power and coherence measures. Anomalies in EEG coherence and power have been associated with deficits in executive function and mental activity. The present study examined...
Show moreAutism is a neurodevelopmental disorder that is characterized by deficits involving social interaction, communication, and perception. Although there is much research that has examined functional neural connectivity in individuals with autism, few have conducted these studies in very young children while awake across EEG power and coherence measures. Anomalies in EEG coherence and power have been associated with deficits in executive function and mental activity. The present study examined neural activation and functional connectivity with an EEG, in children ages 3 -5, during an eyesclosed baseline period. Discrete Fourier Transform was performed on artifact-free segments of EEG data to produce power density values. In addition, coherence measurements were examined to assess functional connectivity in the alpha bandwidth during the baseline recording. Children with autism spectrum disorder (ASD) demonstrated reduced alpha coherence in fronto-temporal regions and between right temporal sites when compared to typically developing (TD) children. In addition, the reduction in coherence was based on ASD severity, such that high-functioning children with ASD showed greater coherence than low-functioning children with ASD. Children with ASD also displayed reduced power in the alpha, beta, and theta frequency bandwidths in frontal, temporal, central, and occipital regions compared to TD children. Interestingly, delta power differentiated children based on developmental status such that high-functioning children with ASD demonstrated the greatest delta power, followed by TD children, and then low-functioning children with ASD. Finally, TD children demonstrated left anterior temporal EEG asymmetry in the alpha bandwidth, whereas children with high-functioning ASD exhibited left posterior temporal EEG asymmetry and right frontal EEG asymmetry. Thus, the results suggest that children with ASD exhibit atypical patterns of brain activity and functional connectivity compared to their typically developing counterparts.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fau/fd/FA0004034
- Subject Headings
- Autism in children -- Research, Autism spectrum disorders, Cognition disorders in children, Cognitive neuroscience, Electroencephalography -- Therapeutic use
- Format
- Document (PDF)
- Title
- The neural correlates of endogenously cued covert visuospatial attentional shifting in the cue-target interval: an electroencephalographic study.
- Creator
- Modestino, Edward Justin., Charles E. Schmidt College of Science, Center for Complex Systems and Brain Sciences
- Abstract/Description
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This study investigated electroencephalographic differences related to cue (central left- or right-directed arrows) in a covert endogenous visual spatial attention task patterned after that of Hopf and Mangun (2000). This was done with the intent of defining the timing of components in relation to cognitive processes within the cue-target interval. Multiple techniques were employed to do this. Event-related potentials (ERPs) were examined using Independent Component Analysis. This revealed a...
Show moreThis study investigated electroencephalographic differences related to cue (central left- or right-directed arrows) in a covert endogenous visual spatial attention task patterned after that of Hopf and Mangun (2000). This was done with the intent of defining the timing of components in relation to cognitive processes within the cue-target interval. Multiple techniques were employed to do this. Event-related potentials (ERPs) were examined using Independent Component Analysis. This revealed a significant N1, between 100:200 ms post-cue, greater contralateral to the cue. Difference wave ERPs, left minus right cue-locked data, divulged significant early directing attention negativity (EDAN) at 200:400 ms post-cue in the right posterior which reversed polarity in the left posterior. Temporal spectral evolution (TSE) analysis of the alpha band revealed three stages, (1) high bilateral alpha precue to 120 ms post-cue, (2) an event related desynchronization (ERD) from approximately 120 ms: 500 ms post-cue, and (3) an event related synchronization (ERS) rebound, 500: 900 ms post-cue, where alpha amplitude, a measure of activity, was highest contralateral to the ignored hemifield and lower contralateral to the attended hemifield. Using a combination of all of these components and scientific literature in this field, it is possible to plot out the time course of the cognitive events and their neural correlates.
Show less - Date Issued
- 2009
- PURL
- http://purl.flvc.org/FAU/369199
- Subject Headings
- Brain mapping, Neural networks (Neurobiology), Cognitive neuroscience, Recognition (Psychology), Cognition, Research, Methodology
- Format
- Document (PDF)
- Title
- Selective Activation of the SK1 Subtype of Small Conductance Ca2+ Activated K+ Channels by GW542573X in C57BL6J Mice Impairs Hippocampal-dependent Memory.
- Creator
- Rice Kuchera, Claire A., Stackman, Robert W., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Psychology
- Abstract/Description
-
SK channels are small conductance Ca2+-activated K+ channels expressed throughout the CNS. SK channels modulate the excitability of hippocampal CA1 neurons by affecting afterhyperpolarization and shaping excitatory postsynaptic responses. Such SK-mediated effects on activity-dependent neuronal excitability and synaptic strength are thought to underlie the modulatory influence of SK channels on memory encoding. Here,the effect of a new SK1 selective activator, GW542573X, on hippocampal...
Show moreSK channels are small conductance Ca2+-activated K+ channels expressed throughout the CNS. SK channels modulate the excitability of hippocampal CA1 neurons by affecting afterhyperpolarization and shaping excitatory postsynaptic responses. Such SK-mediated effects on activity-dependent neuronal excitability and synaptic strength are thought to underlie the modulatory influence of SK channels on memory encoding. Here,the effect of a new SK1 selective activator, GW542573X, on hippocampal-dependent object memory, contextual and cued conditioning, and trace fear conditioning was examined. The results demonstrated that pre- but not post-training systemic administration of GW542573X impaired object memory and trace fear memory in mice 24 h after training. Contextual and cued fear memory were not disrupted. These current data suggest that activation of SK1 subtype-containing SK channels impairs long-term memory. These results are consistent with converging evidence that SK channel activation suppressed behaviorally triggered synaptic plasticity necessary for encoding hippocampal-dependent memory.
Show less - Date Issued
- 2015
- PURL
- http://purl.flvc.org/fau/fd/FA00004541, http://purl.flvc.org/fau/fd/FA00004541
- Subject Headings
- Cellular control mechanisms, Cognitive neuroscience, Cognitive psychology, Hippocampus (Brain), Mice as laboratory animals, Neurotransmitter receptors
- Format
- Document (PDF)
- Title
- Neural and behavioral correlates of song prosody.
- Creator
- Gordon, Reyna Leigh., Charles E. Schmidt College of Science, Center for Complex Systems and Brain Sciences
- Abstract/Description
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This dissertation studies the neural basis of song, a universal human behavior. The relationship of words and melodies in the perception of song at phonological, semantic, melodic, and rhythmic levels of processing was investigated using the fine temporal resolution of Electroencephalography (EEG). The observations reported here may shed light on a ubiquitous human experience and also inform the discussion of whether language and music share neural resources or recruit domain-specific neural...
Show moreThis dissertation studies the neural basis of song, a universal human behavior. The relationship of words and melodies in the perception of song at phonological, semantic, melodic, and rhythmic levels of processing was investigated using the fine temporal resolution of Electroencephalography (EEG). The observations reported here may shed light on a ubiquitous human experience and also inform the discussion of whether language and music share neural resources or recruit domain-specific neural mechanisms. Experiment 1 was designed to determine whether words and melody in song are processed interactively or independently. Participants listened to sung words in which the melodies and/or the words were similar or different, and performed a same/different task while attending to the linguistic and musical dimensions in separate blocks of trials. Event-Related Potentials and behavioral data converged in showing interactive processing between the linguistic and musical dimensions of sung words, regardless of the direction of attention. In particular, the N400 component, a well-established marker of semantic processing, was modulated by musical melody. The observation that variations in musical features affect lexico-semantic processing in sung language was a novel finding with implications for shared neural resources between language and music. Experiment 2 was designed to explore the idea that well-aligned text-settings, in which the strong syllables occur on strong beats, capture listeners' attention and help them understand song lyrics. EEG was recorded while participants listened to sung sentences whose linguistic stress patterns were well-aligned, misaligned, or had variable alignment with the musical meter, and performed a lexical decision task on subsequently presented visual targets., Results showed that induced beta and evoked gamma power were modulated differently for well-aligned and misaligned syllables, and that task performance was adversely affected when visual targets followed misaligned and varied sentences. These findings suggest that alignment of linguistic stress and musical meter in song enhance beat tracking and linguistic segmentation by entraining periodic fluctuations in high frequency brain activity to the stimuli. A series of follow-up studies has been outlined to further investigate the relationship between rhythmic attending in speech and music, and the influence of metrical alignment in songs on childhood language acquisition.
Show less - Date Issued
- 2010
- PURL
- http://purl.flvc.org/FAU/2705078
- Subject Headings
- Cognitive neuroscience, Learning, Physiological aspects, Cognition in children, Physiological aspects, Prosodic analysis (Linguistics)
- Format
- Document (PDF)
- Title
- Brain dynamics and behavioral basis of a higher level cognitive task: number comparison.
- Creator
- Ballan, Meltem., Charles E. Schmidt College of Science, Center for Complex Systems and Brain Sciences
- Abstract/Description
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Number perception, its neural basis and its relationship to how numerical stimuli are presented have been challenging research topics in cognitive neuroscience for many years. A primary question that has been addressed is whether the perception of the quantity of a visually presented number stimulus is dissociable from its early visual perception. The present study examined the possible influence of visual quality judgment on quantity judgments of numbers. To address this issue, volunteer...
Show moreNumber perception, its neural basis and its relationship to how numerical stimuli are presented have been challenging research topics in cognitive neuroscience for many years. A primary question that has been addressed is whether the perception of the quantity of a visually presented number stimulus is dissociable from its early visual perception. The present study examined the possible influence of visual quality judgment on quantity judgments of numbers. To address this issue, volunteer adult subjects performed a mental number comparison task in which two-digit stimulus numbers (Arabic number format), among the numbers between 31 and 99 were mentally compared to a memorized reference number, 65. Reaction times (RTs) and neurophysiological (i.e. electroencephalographic (EEG) data) responses were acquired simultaneously during performance of the two-digit number comparison task. In this particular quantity comparison task, the number stimuli were classified into three distance factors. That is, numbers were a close, medium or far distance from the reference number (i.e., 65). In order to evaluate the relationship between numerical stimulus quantity and quality, the number stimuli were embedded in varying degrees of a typical visual noise form, known as "salt and pepper noise" (e.g., the visual noise one perceives when viewing a photograph taken with a dusty camera lens). In this manner, the visual noise permitted visual quality to be manipulated across three levels: no noise, medium noise (approximately 60% degraded visual quality from nonoise), and dense noise (75% degraded visual quality from no-noise)., The RTs provided the information about the overt responses; however, the temporal relationship of visual quality (starts earlier than quantity perception) and quantity were examined using eventrelated potentials (ERPs) extracted from continuous EEG recordings. The analysis of the RTs revealed that the judgment of number quantity is dependent upon visual number quality. In addition, the same effect was observed over the ERP components occurring between 100 ms and 300 ms after stimulus onset time over the posterior electrodes. Principal components analysis (PCA) and independent component analysis (ICA) methods were used to further analyze the ERP data. The consistent results of the PCA and ICA were used to represent the spatial brain dynamics, as well as to obtain temporal dynamics. The overall conclusion of the present study is that ERPs, ICs and PCs along with RTs suggested a strategy of quantitative perception (i.e., number comparison) based on the qualitative attributes of the stimuli highlighting the importance of the design of the task and the methodology
Show less - Date Issued
- 2010
- PURL
- http://purl.flvc.org/FAU/2867328
- Subject Headings
- Cognitive neuroscience, Learning, Physiological aspects, Visual perception, Information visualization, Mathematics, Philosophy
- Format
- Document (PDF)
- Title
- Affect coding within the therapeutic relationship.
- Creator
- Luedke, Ashley J., College of Education, Department of Counselor Education
- Abstract/Description
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This study investigates affect coding within the therapeutic relationship, by exploring the client's and therapist's perception of the relationship and the facial and vocal affect expressed by both parties. A sample of 14 therapy sessions each having 1800 data points was collected. The Working Alliance Inventory Short Form (WAI-S) and Real Relationship Inventory (RRI) were completed after each recorded session. The participants were therapists and clients at a university counseling center in...
Show moreThis study investigates affect coding within the therapeutic relationship, by exploring the client's and therapist's perception of the relationship and the facial and vocal affect expressed by both parties. A sample of 14 therapy sessions each having 1800 data points was collected. The Working Alliance Inventory Short Form (WAI-S) and Real Relationship Inventory (RRI) were completed after each recorded session. The participants were therapists and clients at a university counseling center in South Florida. Data were analyzed using one-tailed t tests, descriptive statistics, scores from RRI and the WAI-S and percentages of negative, neutral and positive affect. Statistically significant relationships were found between seconds of therapist negative affect (t(13)= -2.065, p. <.05) and seconds of therapist neutral affect (t(13)= -1.959, p. <.05) for clients who dropped out of therapy. The seconds of negative affect coded for clients (t(13) = -1.396, p. >.05) was approaching statistical significance for clients who drop out of therapy. This study provides theoretical and empirical support for linking the presence of facial affect in the first session and its effects on the therapeutic relationship and thus client retention or drop out. The clinical implications of these findings are also discussed.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fcla/dt/3362484
- Subject Headings
- Cognitive neuroscience, Interpersonal communication, Body language, Research, Methodology, Affect (Psychology), Psychotherapist and patient
- Format
- Document (PDF)
- Title
- The influrence of language on recognition memory for motion.
- Creator
- Karaman, Ferhat., Charles E. Schmidt College of Science, Department of Psychology
- Abstract/Description
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Satellite-framed languages and verb-framed languages differ in how they encode motion events. English encodes or lexicalizes Path in verb particles, prepositional phrases, or satellites associated with the main verb. In contrast, Turkish tends to encode Path in the main verb of a clause. When describing motion events, English speakers typically use verbs that convey information about manner rather than path, whereas Turkish speakers do the opposite. In this study, we investigated whether this...
Show moreSatellite-framed languages and verb-framed languages differ in how they encode motion events. English encodes or lexicalizes Path in verb particles, prepositional phrases, or satellites associated with the main verb. In contrast, Turkish tends to encode Path in the main verb of a clause. When describing motion events, English speakers typically use verbs that convey information about manner rather than path, whereas Turkish speakers do the opposite. In this study, we investigated whether this crosslinguistic difference between English and Turkish influences how the speakers of these languages perform in a non-linguistic recognition memory task. In a video description task, English speakers used more manner verbs in the main verb of sentences than Turkish speakers did. In the recognition memory task, English speakers attended more strongly than Turkish speakers did to path of motion. English and Turkish speakers attended equally to manner of motion, however, providing no support for the linguistic relativity hypothesis.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fcla/dt/3362478
- Subject Headings
- Psycholinguistics, Computational neuroscience, Cognitive psychology, Context effects (Psychology), Transference (Psychology), Motion segmentation
- Format
- Document (PDF)
- Title
- Validating music therapy and its effectiveness in treating brain disorders: the role of emotions in music and in therapy.
- Creator
- Hurley, Kristin Renee., Dorothy F. Schmidt College of Arts and Letters, Department of Music
- Abstract/Description
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The success of the music therapy profession has been well established, though the healing properties of music are not yet fully understood. Clinical observations show the medicinal value of music therapy; however, it is challenging to quantify music's beneficial effects. Examining music therapy's effectiveness in treating neurological disorders can possibly help to better validate this profession. However, music therapy is a multidisciplinary field, and perhaps we must come to a better...
Show moreThe success of the music therapy profession has been well established, though the healing properties of music are not yet fully understood. Clinical observations show the medicinal value of music therapy; however, it is challenging to quantify music's beneficial effects. Examining music therapy's effectiveness in treating neurological disorders can possibly help to better validate this profession. However, music therapy is a multidisciplinary field, and perhaps we must come to a better understanding of how the various disciplines relate to one another. Music has the power to modulate our emotions. Neurological studies involving music therapy might help to uncover the connection between our emotional states and our physical health. To truly understand the success of music therapy, we must further study the role of emotions in the healing process. Future examinations of the emotional factor in music therapy may hold the key to a better understanding of how music affects us.
Show less - Date Issued
- 2008
- PURL
- http://purl.flvc.org/FAU/165942
- Subject Headings
- Music, Psychological aspects, Cognitive neuroscience, Healing, Psychological aspects, Medicine and psychology, Mind and body
- Format
- Document (PDF)
- Title
- Uncovering the role of the rodent dorsal hippocampus in spatial and object memory retrieval.
- Creator
- Rios, Lisa, Charles E. Schmidt College of Science, Department of Psychology
- Abstract/Description
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Male C7BL/6J mice were implanted with bilateral dorsal CA1 guide cannulae. After confirming that intrahippocampal microinfusion of muscimol impaired hippocampal function, demonstrated by impaired performance in the Morris water maze, the influence of intrahippocampal muscimol was tested in the Novel Object Recognition paradigm. During a test session 24 h after the last habituation/sample session, mice were presented with one familiar object and one novel object. Successful retention of object...
Show moreMale C7BL/6J mice were implanted with bilateral dorsal CA1 guide cannulae. After confirming that intrahippocampal microinfusion of muscimol impaired hippocampal function, demonstrated by impaired performance in the Morris water maze, the influence of intrahippocampal muscimol was tested in the Novel Object Recognition paradigm. During a test session 24 h after the last habituation/sample session, mice were presented with one familiar object and one novel object. Successful retention of object memory was inferred if mice spent more time exploring the novel object than the familiar object. Results demonstrate that muscimol infused into dorsal CA1 region prior to the test session eliminates novel object preference, indicating that the hippocampus is necessary for the retrieval of this non-spatial memory - a topic that has garnered much debate. Understanding the similarities between rodent and human hippocampal function could enable future animal studies to effectively answer questions about diseases and disorders affecting human learning and memory.
Show less - Date Issued
- 2011
- PURL
- http://purl.flvc.org/FAU/3172696
- Subject Headings
- Rodents as laboratory animals, Memory, Research, Cellular signal transduction, Cognitive neuroscience, Hippocampus (Brain), Space perception
- Format
- Document (PDF)