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Background: Noninvasive MRI methods that can accurately detect subtle brain changes are highly desirable when studying disease-modifying interventions. Texture analysis is a novel imaging technique which utilizes the extraction of a large number of image features with high specificity and predictive power. In this investigation, we use texture analysis to

Background: Noninvasive MRI methods that can accurately detect subtle brain changes are highly desirable when studying disease-modifying interventions. Texture analysis is a novel imaging technique which utilizes the extraction of a large number of image features with high specificity and predictive power. In this investigation, we use texture analysis to assess and classify age-related changes in the right and left hippocampal regions, the areas known to show some of the earliest change in Alzheimer's disease (AD). Apolipoprotein E (APOE)'s e4 allele confers an increased risk for AD, so studying differences in APOE e4 carriers may help to ascertain subtle brain changes before there has been an obvious change in behavior. We examined texture analysis measures that predict age-related changes, which reflect atrophy in a group of cognitively normal individuals. We hypothesized that the APOE e4 carriers would exhibit significant age-related differences in texture features compared to non-carriers, so that the predictive texture features hold promise for early assessment of AD. Methods: 120 normal adults between the ages of 32 and 90 were recruited for this neuroimaging study from a larger parent study at Mayo Clinic Arizona studying longitudinal cognitive functioning (Caselli et al., 2009). As part of the parent study, the participants were genotyped for APOE genetic polymorphisms and received comprehensive cognitive testing every two years, on average. Neuroimaging was done at Barrow Neurological Institute and a 3D T1-weighted magnetic resonance image was obtained during scanning that allowed for subsequent texture analysis processing. Voxel-based features of the appearance, structure, and arrangement of these regions of interest were extracted utilizing the Mayo Clinic Python Texture Analysis Pipeline (pyTAP). Algorithms applied in feature extraction included Grey-Level Co-Occurrence Matrix (GLCM), Gabor Filter Banks (GFB), Local Binary Patterns (LBP), Discrete Orthogonal Stockwell Transform (DOST), and Laplacian-of-Gaussian Histograms (LoGH). Principal component (PC) analysis was used to reduce the dimensionality of the algorithmically selected features to 13 PCs. A stepwise forward regression model was used to determine the effect of APOE status (APOE e4 carriers vs. noncarriers), and the texture feature principal components on age (as a continuous variable). After identification of 5 significant predictors of age in the model, the individual feature coefficients of those principal components were examined to determine which features contributed most significantly to the prediction of an aging brain. Results: 70 texture features were extracted for the two regions of interest in each participant's scan. The texture features were coded as 70 initial components andwere rotated to generate 13 principal components (PC) that contributed 75% of the variance in the dataset by scree plot analysis. The forward stepwise regression model used in this exploratory study significantly predicted age, accounting for approximately 40% of the variance in the data. The regression model revealed 5 significant regressors (2 right PC's, APOE status, and 2 left PC by APOE interactions). Finally, the specific texture features that contributed to each significant PCs were identified. Conclusion: Analysis of image texture features resulted in a statistical model that was able to detect subtle changes in brain integrity associated with age in a group of participants who are cognitively normal, but have an increased risk of developing AD based on the presence of the APOE e4 phenotype. This is an important finding, given that detecting subtle changes in regions vulnerable to the effects of AD in patients could allow certain texture features to serve as noninvasive, sensitive biomarkers predictive of AD. Even with only a small number of patients, the ability for us to determine sensitive imaging biomarkers could facilitate great improvement in speed of detection and effectiveness of AD interventions..
ContributorsSilva, Annelise Michelle (Author) / Baxter, Leslie (Thesis director) / McBeath, Michael (Committee member) / Presson, Clark (Committee member) / School of Life Sciences (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
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We compared sociability towards humans of domesticated and tame members of several Canidae: Belyaev's fox (Vulpes vulpes), red fox (Vulpes vulpes), gray wolf (Canis lupus), dingo (Canis l. dingo), New Guinea singing dog (Canis l. dingo), and dog (Canis l. familiaris). We defined sociability as motivation or willingness to engage

We compared sociability towards humans of domesticated and tame members of several Canidae: Belyaev's fox (Vulpes vulpes), red fox (Vulpes vulpes), gray wolf (Canis lupus), dingo (Canis l. dingo), New Guinea singing dog (Canis l. dingo), and dog (Canis l. familiaris). We defined sociability as motivation or willingness to engage with humans. Our operationalized definition of sociability is the latency to approach (LTA) the human experimenter and the amount of time the canid spent within one meter of the human experimenter (PTC). We added an unfamiliar and familiar experimenter condition to deduce whether or not canids discriminated on who they were more social with: an owner or a stranger. To each experimenter condition we added a passive and active phase to discern whether or not canids were more social when called or not. Across all conditions and phases dogs were significantly more social than all other canid types. We concluded genetic differences due to domestication and environmental differences due to socialization accounted for sociability differences seen in dogs compared to the other canid types.
ContributorsBeckstrom-Sternberg, David Tristan (Author) / Wynne, Clive (Thesis director) / McBeath, Michael (Committee member) / School of International Letters and Cultures (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
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Description
Background: Gait disturbance, clumsiness, and other mild movement problems are often observed in children with autism spectrum disorder (ASD) (Maurer and Damasio 1982). As the brain ages, these symptoms may persist or worsen in late adulthood in those diagnosed with ASD. This study focused on older adults with ASD to

Background: Gait disturbance, clumsiness, and other mild movement problems are often observed in children with autism spectrum disorder (ASD) (Maurer and Damasio 1982). As the brain ages, these symptoms may persist or worsen in late adulthood in those diagnosed with ASD. This study focused on older adults with ASD to study motor behavior and underlying brain integrity. Using a finger tapping task, motor performance was measured in a cross-sectional study comparing older adults with ASD and age-matched typically developing (TD) controls. We hypothesized that older adults with ASD would show poorer motor performance (slower finger tapping speed). We also hypothesized that underlying brain differences, measured using MRI, in regions associated with motor function including the primary motor cortex, basal ganglia, and cerebellum, as well as the white matter connecting tracts would exist between groups and be associated with the proposed disparity in motor performance.

Method: A finger oscillation (Finger Tapping) test was administered to both ASD (n=21) and TD (n=20) participants aged 40-70 year old participants as a test of fine motor speed. Magnetic resonance (MR) images were collected using a Philips 3 Tesla scanner. 3D T1-weighted and diffusion tensor images (DTI) were obtained to measure gray and white matter volume and white matter integrity, respectively. FreeSurfer, an automated volumetric measurement software, was used to determine group volumetric differences. Mean, radial, and axial diffusivity, fractional anisotropy, and local diffusion homogeneity were measured from DTI images using PANDA software in order to evaluate white matter integrity.

Results: All participants were right-handed and there were no significant differences in demographic variables (ASD/TD, means) including age (51.9/49.1 years), IQ (107/112) and years education (15/16). Total brain volume was not significantly different between groups. No statistically significant group differences were observed in finger tapping speed. ASD participants compared to TDs showed a trend of slower finger tapping (taps/10 seconds) speed on the dominant hand (47.00 (±11.2) vs. (50.5 (±6.6)) and nondominant hand (44.6 (±7.6) vs. (47.2 (±6.6)). However, a large degree of variability was observed in the ASD group, and the Levene’s test for homogeneity of variance approached significance (p=0.053) on the dominant, but not the nondominant, hand. No significant group differences in gray matter regional volume were found for brain regions associated with performing motor tasks. In contrast, group differences were found on several measures of white matter including the corticospinal tract, anterior internal capsule and middle cerebellar peduncle. Brain-behavior correlations showed that dominant finger tapping speed correlated with left hemisphere white matter integrity of the corticospinal tract and right hemisphere cerebellar white matter in the ASD group.

Conclusions: No significant differences were observed between groups in finger tapping speed but the high degree of variability seen in the ASD group. Differences in motor performance appear to be associated with observed brain differences, particularly in the integrity of white matter tracts contributing to motor functioning.
ContributorsDeatherage, Brandon R. (Co-author) / Braden, B. Blair (Co-author, Committee member) / Smith, Christopher J. (Co-author) / McBeath, Michael (Co-author, Thesis director) / Thompson, Aimee M. (Co-author) / Wood, Emily G. (Co-author) / McGee, Samuel C. (Co-author) / Sinha, Krishna (Co-author) / Baxter, Leslie (Co-author, Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor) / Department of Information Systems (Contributor)
Created2017-05
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Description
In baseball, the difference between a win and loss can come down to a single call, such as when an umpire judges force outs at first base by typically comparing competing auditory and visual inputs of the ball-mitt sound and the foot-on-base sight. Yet, because the speed of sound in

In baseball, the difference between a win and loss can come down to a single call, such as when an umpire judges force outs at first base by typically comparing competing auditory and visual inputs of the ball-mitt sound and the foot-on-base sight. Yet, because the speed of sound in air only travels about 1100 feet per second, fans observing from several hundred feet away will receive auditory cues that are delayed a significant portion of a second, and thus conceivably could systematically differ in judgments compared to the nearby umpire. The current research examines two questions. 1. How reliably and with what biases do observers judge the order of visual versus auditory events? 2. Do observers making such order judgments from far away systematically compensate for delays due to the slow speed of sound? It is hypothesized that if any temporal bias occurs it is in the direction consistent with observers not accounting for the sound delay, such that increasing viewing distance will increase the bias to assume the sound occurred later. It was found that nearby observers are relatively accurate at judging if a sound occurred before or after a simple visual event (a flash), but exhibit a systematic bias to favor visual stimuli occurring first (by about 30 msec). In contrast, distant observers did not compensate for the delay of the speed of sound such that they systematically favored the visual cue occurring earlier as a function of viewing distance. When observers judged simple visual stimuli in motion relative to the same sound burst, the distance effect occurred as a function of the visual clarity of the ball arriving. In the baseball setting, using a large screen projection of baserunner, a diminished distance effect occurred due to the additional visual cues. In summary, observers generally do not account for the delay of sound due to distance.
ContributorsKrynen, R. Chandler (Author) / McBeath, Michael (Thesis advisor) / Homa, Donald (Committee member) / Gray, Robert (Committee member) / Arizona State University (Publisher)
Created2017
Description

This study investigates the effects of familiarity and the size of a novel object on perception of depth. Familiar size is a visual depth cue that provides information about the distance of an object. This project explores if the familiar size illusion is a result of an automatic perceptual process

This study investigates the effects of familiarity and the size of a novel object on perception of depth. Familiar size is a visual depth cue that provides information about the distance of an object. This project explores if the familiar size illusion is a result of an automatic perceptual process or an intellectual thought process. This data was collected in two phases, a familiarization phase and a testing phase. The experimental participants were familiarized for 30 seconds with a novel object, while the control group was not shown any objects prior to presentation of test objects. The novel test stimuli were constructed in 5 sizes and participants in the familiar group were familiarized with the medium size object. Participants were then asked to indicate the perceived distance of different sized objects by moving a rod with a pointer at the end to match the distance. The smaller comparison objects subtended visual angles that participants had not previously experienced, while larger comparison objects produced a larger visual angle than the participants had seen during the familiarization phase. The testing phase was identical for both familiar and unfamiliar control groups. Apparent distance was influenced by the size of the objects. Larger objects were judged to be closer than the smaller objects. Participants not familiarized showed smaller effects of stimulus size than the familiarized group. The effect of familiarity was not significant for the smaller stimuli but was very significant for the larger stimuli. The results were not consistent with the cognitive theory which argues that familiar size is a result of a conscious thought process. These outcomes are predicted under the model of familiar size being an automatic perceptual process.

ContributorsLawrence, Sahana (Author) / Yonas, Albert (Thesis director) / McBeath, Michael (Committee member) / Fabricius, William (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2023-05
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Description
Recent findings support that facial musculature accounts for a form of phonetic sound symbolism. Yu, McBeath, and Glenberg (2019) found that, in both English words and Mandarin pinyin, words with the middle phoneme /i:/ (as in “gleam”) were rated as more positive than their paired words containing the phoneme /ʌ

Recent findings support that facial musculature accounts for a form of phonetic sound symbolism. Yu, McBeath, and Glenberg (2019) found that, in both English words and Mandarin pinyin, words with the middle phoneme /i:/ (as in “gleam”) were rated as more positive than their paired words containing the phoneme /ʌ/ (as in “glum”). The present study tested whether a second largely orthogonal dimension of vowel phoneme production (represented by the phonemes /æ/ vs /u/), is related to a second dimension perpendicular to emotional valence, arousal. Arousal was chosen because it is the second dimension of the Russell Circumplex Model of Affect. In phonetic similarity mappings, this second dimension is typically characterized by oral aperture size and larynx position, but it also appears to follow the continuum of consonance/dissonance. Our findings supported the hypothesis that one-syllable words with the center vowel phoneme /æ/ were reliably rated as more rousing, and less calming, than matched words with the center vowel phoneme /u/. These results extend the Yu, et al. findings regarding the potential contribution of facial musculature to sounds associated with the emotional dimension of arousal, and further confirm a model of sound symbolism related to emotional expression. These findings support that phonemes are not neutral basic units but rather illustrate an innate relationship between embodied emotional expression and speech production.
ContributorsGreenstein, Ely Conrad (Author) / McBeath, Michael (Thesis director) / Glenberg, Arthur (Committee member) / Patten, Kristopher (Committee member) / Historical, Philosophical & Religious Studies (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05