Paradigm In Conjunction Research Articles

Non-invasive measurement of rat auditory evoked fields using an optically pumped atomic magnetometer: Effects of task manipulation

Optically pumped magnetometers (OPMs) have become a favorable tool for magnetoencephalography (MEG) measurement, offering a non-invasive method of measurement. OPMs do not require cryogenic environments, sensors can be more closely aligned with the brain. We employed a passive single-stimulus paradigm in conjunction with OPMs with a sensitivity of 20 fT/ Hz to investigate the auditory response of rats to inter-stimulus interval (ISI) and frequencies, recording the rat auditory event-related magnetic fields (ERMFs). Our findings include: (1) Auditory evoked fields can be detected non-invasively by OPMs; (2) The amplitude of the rat auditory ERMFs varies with changes in ISI, with more pronounced amplitude changes observed after 5 s; (3) When the sound stimulus frequency is altered at the same ISI, the amplitude of the rats ERMFs changes with frequency, indicating significant differences in attention. Our method offers a valuable tool for the clinical application of a single stimulus paradigm and opens up a new avenue for research on the brain magnetic field detections.

Systematic Literature Review of Chemistry Learning to Improve Students’ Creative Thinking Skills

The purpose of this study is to discuss novel approaches to teaching chemistry that enhance students' creative thinking skills (CTSs), as well as the kinds of research that are conducted and the tools that are used to measure CTSs. . This research use the PRISMA paradigm in conjunction with a systematic literature review approach. This method was employed by searching for Google Scholar. The analysis results of eight relevant journals and proceeding articles show five articles discussing the implementation of chemistry learning strategies to improve students’ CTSs, with the distribution as follows: problem-based learning-scaffolding, STEAM-PjBL, case-based Learning, STMCpE textbooks based on chemo-entrepreneurship, and students’ worksheet with the mind mapping strategy which amounts to 20.00% each. The types of research used were experimental methods (37.50%), research and developmental methods (12.50%), survey research (12.50%), ex post facto research (12.50%), and qualitative research (descriptive approach) (25.00%). Instruments for measuring CTSs are in the form of a CTS test with indicators developed by Torrance (75.00%), non-test (interview and observation) (12.50%), and unclear instrument (12.50%).

Influence of varying carbon oxides concentrations on the selectivity of an electrical sensor utilizing graphene nanoribbons

We have considered a graphene nano ribbon-based two probe-device working on the principle of alteration of current-voltage (I–V) characteristic, upon interactions of its channel material with the adsorbed gas molecules. The analysis of sensing parameters alongside the electron transport mechanism was carried out by using density functional theory (DFT) formulated on the Hohenberg-Kohen paradigm in conjunction with the non-equilibrium green functions (NEGF) method. Electronic transport through similar work reported earlier reveals that the combination of these two techniques coordinates extremely well and yields convincing electronic results. The nanoribbon-based sensing device was employed to evaluate its capability to detect Carbon dioxide (CO2) and Carbon monoxide (CO) molecules. Analysis of the computed result reveals significant modifications in the electronic property of the device upon adsorption of carbon dioxide and carbon monoxide entities on the channel surface. One such significant and dramatic change in the characteristic that we observed is the nature of the channel that transforms from metallic to semi-metallic. Another observed change is the signal amplification capability relative to the pristine device. The signal gets amplified on increasing number of molecular entities from one to six.The transformation in sensor performance is additionally supported by examining variations in multiple parameters, including adsorption energy, charge transfer, differential resistance, and the figure of merit, also known as the peak-to-valley ratio (PVR). The investigation unveiled that the currently designed zigzag graphene nanoribbon (ZGNR) model exhibits high sensitivity to both CO2 and CO gases. This phenomenon is substantiated by the elevated adsorption energy, increased charge transfer, elevated peak-to-valley ratio (PVR), and heightened sensor response. The substantial sensor response, registering at a magnitude of 8.3, underscores the efficacy of the current system in detecting both low and high concentrations of CO and CO2 molecules. The current study emphasizes the notion that understanding the electronic and transport behaviour of zigzag graphene nanoribbons (ZGNR) and analogous materials could offer valuable insights for addressing the threat of environmental pollution.

Impairment of unconscious emotional processing after unilateral medial temporal structure resection

The role of the amygdala in unconscious emotional processing remains a topic of debate. Past lesion studies have indicated that amygdala damage leads to impaired electrodermal activity in response to subliminally presented emotional stimuli. However, electrodermal activity can reflect both emotional and nonemotional processes. To provide behavioral evidence highlighting the critical role of the amygdala in unconscious emotional processing, we examined patients (n = 16) who had undergone unilateral resection of medial temporal lobe structures, including the amygdala. We utilized the subliminal affective priming paradigm in conjunction with unilateral visual presentation. Fearful or happy dynamic facial expressions were presented in unilateral visual fields for 30 ms, serving as negative or positive primes. Subsequently, neutral target faces were displayed, and participants were tasked with rating the valence of these targets. Positive primes, compared to negative ones, enhanced valence ratings of the target to a greater extent when they stimulated the intact hemisphere (i.e., were presented in the contralateral visual field of the intact hemisphere) than when they stimulated the resected hemisphere (i.e., were presented in the contralateral visual field of the resected hemisphere). These results suggest that the amygdala is causally involved in unconscious emotional processing.

Comparison of Event‐Related Potential Markers in Amyloid Positive vs. Amyloid Negative Patients with Mild Cognitive Impairment (MCI) and Dementia in a general neurological clinic

AbstractBackgroundWe used an automated Event Related Potentials (ERP) technique to compare ERP responses in amyloid positive and negative group of 75 patients with Mild Cognitive Impairment (MCI) and Dementia in a general neurological outpatient clinic. Over the years, research labs have repeatedly reported abnormal ERP markers in patients with MCI and dementia. Recent advances in technology have made ERP testing safe, easy to use and low cost, thus rendering it suitable for clinical use. Indeed, ERPs have become more routinely used in clinical assessment of neurological patients with cognitive changes. The possibility that ERP could help identify amyloid status in MCI and dementia patients adds to the potential clinical utility of these biomarkers.MethodPatients with a history of cognitive complains underwent an auditory oddball ERP paradigm in conjunction with routine neurological evaluation and imaging studies. Standard neuropsychological testing were available in most cases. Amyloid PET imaging was done as part of the IDEAS (Imaging Dementia ‐Evidence for Amyloid Scanning) study and provided the readings for amyloid load.ERP responses were analyzed in the context of beta amyloid readings, and in relation to the patients’ degree of cognitive deficits.ResultFinal data analysis will be presented at the time of the conferenceConclusionThe possibility that ERP could help identify amyloid status in MCI and dementia patients adds to the potential clinical utility of these biomarkers. possibility that ERP could help identify amyloid status in MCI and dementia patients adds to the potential clinical utility of these biomarkers.

Comparison of Event‐Related Potential Markers in Amyloid Positive vs. Amyloid Negative Patients with Mild Cognitive Impairment (MCI) and Dementia in a general neurological clinic

AbstractBackgroundWe used an automated Event Related Potentials (ERP) technique to compare ERP responses in amyloid positive and negative group of 75 patients with Mild Cognitive Impairment (MCI) and Dementia in a general neurological outpatient clinic. Over the years, research labs have repeatedly reported abnormal ERP markers in patients with MCI and dementia. Recent advances in technology have made ERP testing safe, easy to use and low cost, thus rendering it suitable for clinical use. Indeed, ERPs have become more routinely used in clinical assessment of neurological patients with cognitive changes. The possibility that ERP could help identify amyloid status in MCI and dementia patients adds to the potential clinical utility of these biomarkers.MethodPatients with a history of cognitive complains underwent an auditory oddball ERP paradigm in conjunction with routine neurological evaluation and imaging studies. Standard neuropsychological testing were available in most cases. Amyloid PET imaging was done as part of the IDEAS (Imaging Dementia ‐Evidence for Amyloid Scanning) study and provided the readings for amyloid load. ERP responses were analyzed in the context of beta amyloid readings, and in relation to the patients’ degree of cognitive deficits.ResultFinal data analysis will be presented at the time of the conferenceConclusionThe possibility that ERP could help identify amyloid status in MCI and dementia patients adds to the potential clinical utility of these biomarkers. possibility that ERP could help identify amyloid status in MCI and dementia patients adds to the potential clinical utility of these biomarkers.

Time-Domain Structural Damage Identification Using Ensemble Bagged Trees and Evolutionary Optimization Algorithms

This paper presents a two-step vibration-based strategy for damage identification of framed structures using ensemble bagged trees known as a well-known supervised machine learning (ML) paradigm in conjunction with evolutionary optimization algorithms. The proposed model incorporates the actual response, wavelet coefficients, and wavelet energy to extract damage-sensitive features from the time-domain of the measured and simulated signals. Unlike available studies in this scope, the key objective of this research is to identify damage with a localization precision down to a single structural member, rather than limiting the evaluation to the group of elements. In order to increase the training performance in contributing to extremely large datasets with numerous class labels, the proposed strategy involves the artificial generation of features. Additionally, a modified genetic algorithm is proposed for fast damage localization. It is deduced that the damage locations are confidently detected within a fast computational time. Subsequently, damage identification is followed by the application of evolutionary optimization algorithms. For comparison purpose, the employment of the water cycle optimization algorithm (WCA) is comparatively investigated with the other three state-of-the-art optimizers, i.e., particle swarm optimization (PSO), imperialist competitive algorithm (ICA), and differential evolution algorithm (DE). The numerical and experimental validation studies evidence satisfactorily reliable identification results with no false detection in dealing with multiple damage scenarios in large-scale and real-world applications. It is concluded that developing the most damage-sensitive features and using the proposed data fusion strategy lead to informative features with a reasonably small size and significantly improve the ML performance.

Missio Dei as the Main Project: Project Management Model for Mission of God

The emergence of the concept of Missio Dei (Mission of God) from the perspective of the International Missionary Council (IMC) arguably demonstrated that the role of the Triune God in his own mission was undeservedly marginalized for decades, if not centuries preceding 1952. Over the past decades there has been a sustained research activity conceptualizing Missio Dei, and at the same time renewing missiological interest in other Christian missions. However, to the author’s awareness, there has been very little or no effort to introduce or use known project models that can be utilized to show coherence or collaboration of missions towards the project of fulfilling the objective of Missio Dei. Through a desk-top literature review, this paper proposes the use of a project management model to properly conceptualize the location of Missio Dei as a main project that includes other network of missions as sub-projects within its framework. The Triune God is here identified as Project managers while human participants are seen as project stakeholders. Christian missions include Missio Christos, Missio Spiritus, Missio Hominum and Missio Ecclesiae as sub-projects. The proposed model will demonstrate the coordination and collaboration of missions in the broader context of Missio Dei and further assist with a proper understanding of roles that each mission is, or should play, in achieving the objective of Missio Dei. While efforts are being made here to propose a project management model for Missio Dei, further research is needed to determine whether this proposal will yield an in-depth understanding of Missio Dei as a missiological paradigm in conjunction with the role of other missions.

The liver-clock coordinates rhythmicity of peripheral tissues in response to feeding.

The mammalian circadian system consists of a central clock in the brain that synchronizes clocks in peripheral tissues. While the hierarchy between the central and peripheral clocks is established, little is known regarding the specificity and functional organization of peripheral clocks. Here, we employ altered feeding paradigms in conjunction with liver-clock mutant mice to map disparities and interactions between peripheral rhythms. We find that peripheral clocks largely differ in their responses to feeding-time. Disruption of the liver-clock, despite its prominent role in nutrient processing, does not affect rhythmicity of clocks in other peripheral tissues. Yet, unexpectedly, liver-clock disruption strongly modulates peripheral tissues’ transcriptional rhythmicity, primarily upon daytime feeding. Concomitantly, liver-clock mutant mice exhibit impaired glucose and lipid homeostasis, which are aggravated by daytime feeding. Overall, our findings suggest that, upon nutrient challenge, the liver-clock buffers the effect of feeding-related signals on rhythmicity of peripheral tissues, irrespective of their clocks.

Entre el concepto de archivo y el estatuto de lo fotográfico. Walter Benjamin, Roland Barthes y Jacques Derrida, algunos cruces posibles para el análisis de prácticas artísticas contemporáneas.

This paper propose to relate writings by Walter Benjamin, Roland Barthes and Jacques Derrida, in order to review some considerations on the archive paradigm in conjunction with the photographic status. Propose to rethink these notions and open some problems for the analysis of contemporary artistic practices that use photographic archives as a strategy for the appropriation and rereading of representations, experiences and historical meanings. Finally, there are also some intersections between these reflections and a series of Latin American contemporary projects that propose creating collections based on domestic archives photographs.

Do Chinese firms benefit from government ownership following cross-border acquisitions?

Chinese firms’ increasing cross-border acquisitions (CBAs) in recent years seem to challenge the explanatory power of received theories of multinational enterprise (MNE) due to their relatively unique characteristics and the active role of the Chinese government. In this study, we seek to revisit and contextualize the OLI paradigm in conjunction with the institution-based view and examine how Chinese firms’ post-CBA long term performance is associated with government ownership. Our study shows that Chinese firms with more government ownership demonstrate better post-CBA long term performance. However, the above relationship is differentially moderated by such firm-level boundary conditions as political connections and financial slack, and the country-level institutional boundary conditions (i.e., the host country formal institutions and the home-host country cultural distance). We discuss our findings in detail and explore theoretical and practical implications for both Chinese firms and other emerging economy (EE) firms.

The N200 enhancement effect in reading Chinese is modulated by actual writing

Previous research has demonstrated that writing can modulate the orthographic processing of reading in Chinese. We examined whether such a modulatory effect from Chinese writing to reading can occur even when visual feedback is not provided during writing. Using the repetition prime paradigm in conjunction with imagined and actual writing prime tasks, we found that actual but not imagined writing elicited an N200 enhancement effect, which reflects deep orthographic processing in reading Chinese characters at a topographic and ERP level. This effect can be explained by the interaction between writing production processing and the environment during writing execution, which may modulate the subsequent deep orthographic process of reading through a kinesthetic gesture orthographic code system in reading or a tight connection between visual orthography and writing motion. In addition, writing influenced the orthographic processing of Chinese reading in a different way than reading. Our findings suggest that the actual writing process without visual feedback can modulate the orthographic processing in reading Chinese characters, and highlight the crucial role of writing motion in developing Chinese reading ability.

Utilization of functional MRI language paradigms for pre-operative mapping: a systematic review.

Functional MRI (fMRI) can be employed to non-invasively localize brain regions involved in functional areas of language in patients with brain tumour, for applications including pre-operative mapping. The present systematic review was conducted to explore prevalence of different language paradigms utilised in conjunction with fMRI approaches for pre-operative mapping, with the aim of assessing their effectiveness and suitability. A systematic literature search of brain tumours in the context of fMRI methods applied to pre-operative mapping for language functional areas was conducted using PubMed/MEDLINE and Scopus electronic database following PRISMA guidelines. The article search was conducted between the earliest record and March 1, 2019. References and citations were checked in Google Scholar database. Twenty-nine independent studies were identified, comprising 1031 adult participants with 976 patients characterised with different types and sizes of brain tumours, and the remaining 55 being healthy controls. These studies evaluated functional language areas in patients with brain tumours prior to surgical interventions using language-based fMRI. Results demonstrated that 86% of the studies used a Word Generation Task (WGT) to evoke functional language areas during pre-operative mapping. Fifty-seven percent of the studies that used language-based paradigms in conjunction with fMRI as a pre-operative mapping tool were in agreement with intra-operative results of language localization. WGT was most commonly utilised and is proposed as a suitable and useful technique for a language-based paradigm fMRI for pre-operative mapping. However, based on available evidence, WGT alone is not sufficient. We propose a combination and convergence paradigms for a more sensitive and specific map of language function for pre-operative mapping. A standard guideline for clinical applications should be established.

Physiological and pathophysiological evaluation of baroreflex functionality with concurrent diffusion tensor imaging of its neural circuit in the rat

BackgroundBy measuring the prevalence of neuronal traffic between two brain structures based on the notion that diffusion of water molecules along the axon in parallel bundles will create prominent anisotropy in the direction of the passage of action potentials, diffusion tensor imaging (DTI) may be taken as an effective tool for functional investigations. Demonstration of complementary results obtained from synchronized DTI of the baroreflex neural circuit and physiological or pathophysiological evaluation of baroreflex functionality should validate this notion. MethodsWe implemented concurrent changes in neuronal traffic within the neural circuit of the baroreflex-mediated sympathetic vasomotor tone in the brain stem and alterations of its experimental surrogate under physiological and pathophysiological conditions. We further evaluated the functional and clinical implications of results obtained from this experimental paradigm in conjunction with baroreflex induction and a mevinphos intoxication model of brain stem death. ResultsWe found that robust connectivity existed between the nucleus tractus solitarii and rostral ventrolateral medulla, the afferent and efferent nuclei of the baroreflex-mediated sympathetic vasomotor. Intriguingly, this connectivity was either reversibly disrupted or irreversibly severed to reflect alterations in baroreflex responses to physiological or pathophysiological challenges. ConclusionsThe capability to observe simultaneous and complementary changes in neuronal traffic within the neural circuit of the baroreflex-mediated sympathetic vasomotor tone and alterations of its experimental surrogate that bears technical, scientific and clinical implications sustains the notion that coupled with relevant physiological phenotypes, DTI can be an effective investigative tool for functional evaluations of brain stem activities.

Searching for Face-Category Representation in the Avian Visual Forebrain.

Visual information is processed hierarchically along a ventral (‘what’) pathway that terminates with categorical representation of biologically relevant visual percepts (such as faces) in the mammalian extrastriate visual cortex. How birds solve face and object representation without a neocortex is a long-standing problem in evolutionary neuroscience, though multiple lines of evidence suggest that these abilities arise from circuitry fundamentally similar to the extrastriate visual cortex. The aim of the present experiment was to determine whether birds also exhibit a categorical representation of the avian face-region in four visual forebrain structures of the tectofugal visual pathway: entopallium (ENTO), mesopallium ventrolaterale (MVL), nidopallium frontolaterale (NFL), and area temporo-parieto-occipitalis (TPO). We performed electrophysiological recordings from the right and left hemispheres of 13 pigeons while they performed a Go/No-Go task that required them to discriminate between two sets of stimuli that included images of pigeon faces. No neurons fired selectively to only faces in either ENTO, NFL, MVL, or TPO. Birds’ predisposition to attend to the local-features of stimuli may influence the perception of faces as a global combination of features, and explain our observed absence of face-selective neurons. The implementation of naturalistic viewing paradigms in conjunction with electrophysiological and fMRI techniques has the potential to promote and uncover the global processing of visual objects to determine whether birds exhibit category-selective patches in the tectofugal visual forebrain.

Anticipation of Uncertain Threat Modulates Subsequent Affective Responses and Covariation Bias.

Uncertainty contributes to stress and anxiety-like behaviors by impairing the ability of participants to objectively estimate threat. Our study used the cue-picture paradigm in conjunction with the event-related potential (ERP) technique to explore the temporal dynamics of anticipation for and response to uncertain threat in healthy individuals. This task used two types of cue. While ‘certain’ cues precisely forecasted the valence of the subsequent pictures (negative or neutral), the valence of pictures following ‘uncertain’ cues was not predictable. ERP data showed that, during anticipation, uncertain cues elicited similar Stimulus-Preceding Negativity (SPN) to certain-negative cues, while both of them elicited larger SPN than certain-neutral cues. During affective processing, uncertainty enlarged the mean amplitude of late positive potential (LPP) for both negative and neutral pictures. Behavioral data showed that participants reported more negative mood ratings of uncertain-neutral pictures relative to certain-neutral pictures and overestimated the probability of negative pictures following uncertain cues. Importantly, the enlarged anticipatory activity evoked by uncertain cues relative to that evoked by certain-neutral cues positively modulated the more negative mood ratings of uncertain-neutral pictures relative to certain-neutral pictures. Further, this more negative mood ratings and the general arousal anticipation during anticipatory stage contributed to the covariation bias. These results can provide a novel insight into understanding the neural mechanism and pathological basis of anxiety.

Use of event related potential markers in patients with traumatic brain injury

ObjectiveTo investigate whether event related potentials (ERP) could improve diagnosis and management of traumatic brain injury (TBI) patients in an outpatient setting.BackgroundThough important progress has been made in our understanding of how traumatic brain injury (TBI) affects the brain, diagnosis remains suboptimal, especially in the mild stages of the disease. A real time physiologic measure of brain cortical synaptic function such as event related potentials (ERP) can measure the sensory and cognitive deficits that follow TBI even at the subclinical stages of the disease. Even though the potential of ERP as a diagnostic tool for TBI has been known for several years, the impracticality of running ERP tests in clinical environments on real patients has limited widespread clinical application in the past. Recently, advances in electronics and analysis algorithms have made it practical for ERP tests to be administered in outpatient settings on real patients, thus creating an opportunity to evaluate ERP as an index of functional pathophysiology for TBI in clinical environments.Design/methodsThree patients with acute mild TBI were administered an auditory oddball ERP paradigm in conjunction with standard clinical evaluation.ResultsERPs were an informative measure for understanding covert deficits in cognition. Several ERP components revealed selective dysfunction following sport concussion. ERP testing in this case series increased confidence in diagnosis and prognosis for this population of sport-related concussion, thus leading to better patient management. Through this data, we are now equipped with better insight on which TBI patients would benefit most from the addition of ERP testing to the standard clinical workup.ConclusionsAnalysis of ERP data provides valuable information in patients with TBI, especially in mild cases where neuroimaging studies are non-revealing.

Experimental Investigation of the Time Course Effects of Acute Exercise on False Episodic Memory.

Previous experimental work suggests that acute exercise may positively influence the accurate recall of past episodic events. However, few studies have examined whether acute exercise also reduces the number of false episodic memories. We evaluated this paradigm in conjunction with an examination of the temporal effects of acute exercise, which have previously been shown to play an important role in subserving episodic memory function. Twenty young adults participated in three experimental visits, including a non-exercise control visit, a visit involving an acute bout (20 min) of moderate-intensity exercise occurring prior to the memory task, and a visit involving an acute bout of exercise occurring during the encoding of the memory task. All visits were counterbalanced and occurred at least 24 h apart. The Deese–Roediger–McDermott (DRM) Paradigm, involving a separate word list trial for each visit, was employed to assess accurate and false episodic memory recall. For each visit, a short-term (immediate recall) and a long-term (25-min delay) memory recall was assessed. For both time points, the visit that involved exercise prior to encoding resulted in better short-term and long-term memory function (F(2) = 11.56, p < 0.001, η2p = 0.38). For both time points, the control visit resulted in a greater number of false memories. These findings suggest that acute moderate-intensity exercise may help to increase the accurate recall of past episodic memories and may help to reduce the rate of false memories.

Neural practice effect during cross-modal selective attention: Supra-modal and modality-specific effects

Practice and experiences gradually shape the central nervous system, from the synaptic level to large-scale neural networks. In natural multisensory environment, even when inundated by streams of information from multiple sensory modalities, our brain does not give equal weight to different modalities. Rather, visual information more frequently receives preferential processing and eventually dominates consciousness and behavior, i.e., visual dominance. It remains unknown, however, the supra-modal and modality-specific practice effect during cross-modal selective attention, and moreover whether the practice effect shows similar modality preferences as the visual dominance effect in the multisensory environment. To answer the above two questions, we adopted a cross-modal selective attention paradigm in conjunction with the hybrid fMRI design. Behaviorally, visual performance significantly improved while auditory performance remained constant with practice, indicating that visual attention more flexibly adapted behavior with practice than auditory attention. At the neural level, the practice effect was associated with decreasing neural activity in the frontoparietal executive network and increasing activity in the default mode network, which occurred independently of the modality attended, i.e., the supra-modal mechanisms. On the other hand, functional decoupling between the auditory and the visual system was observed with the progress of practice, which varied as a function of the modality attended. The auditory system was functionally decoupled with both the dorsal and ventral visual stream during auditory attention while was decoupled only with the ventral visual stream during visual attention. To efficiently suppress the irrelevant visual information with practice, auditory attention needs to additionally decouple the auditory system from the dorsal visual stream. The modality-specific mechanisms, together with the behavioral effect, thus support the visual dominance model in terms of the practice effect during cross-modal selective attention.

Dopamine depletion impairs gait automaticity by altering cortico-striatal and cerebellar processing in Parkinson's disease

Impairments in motor automaticity cause patients with Parkinson's disease to rely on attentional resources during gait, resulting in greater motor variability and a higher risk of falls. Although dopaminergic circuitry is known to play an important role in motor automaticity, little evidence exists on the neural mechanisms underlying the breakdown of locomotor automaticity in Parkinson's disease. This impedes clinical management and is in great part due to mobility restrictions that accompany the neuroimaging of gait. This study therefore utilized a virtual reality gait paradigm in conjunction with functional MRI to investigate the role of dopaminergic medication on lower limb motor automaticity in 23 patients with Parkinson's disease that were measured both on and off dopaminergic medication. Participants either operated foot pedals to navigate a corridor (‘walk’ condition) or watched the screen while a researcher operated the paradigm from outside the scanner (‘watch’ condition), a setting that controlled for the non-motor aspects of the task. Step time variability during walk was used as a surrogate measure for motor automaticity (where higher variability equates to reduced automaticity), and patients demonstrated a predicted increase in step time variability during the dopaminergic “off” state. During the “off” state, subjects showed an increased blood oxygen level-dependent response in the bilateral orbitofrontal cortices (walk>watch). To estimate step time variability, a parametric modulator was designed that allowed for the examination of brain regions associated with periods of decreased automaticity. This analysis showed that patients on dopaminergic medication recruited the cerebellum during periods of increasing variability, whereas patients off medication instead relied upon cortical regions implicated in cognitive control. Finally, a task-based functional connectivity analysis was conducted to examine the manner in which dopamine modulates large-scale network interactions during gait. A main effect of medication was found for functional connectivity within an attentional motor network and a significant condition by medication interaction for functional connectivity was found within the striatum. Furthermore, functional connectivity within the striatum correlated strongly with increasing step time variability during walk in the off state (r=0.616, p=0.002), but not in the on state (r=−0.233, p=0.284). Post-hoc analyses revealed that functional connectivity in the dopamine depleted state within an orbitofrontal-striatal limbic circuit was correlated with worse step time variability (r=0.653, p<0.001). Overall, this study demonstrates that dopamine ameliorates gait automaticity in Parkinson's disease by altering striatal, limbic and cerebellar processing, thereby informing future therapeutic avenues for gait and falls prevention.