Theses

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https://hdl.handle.net/10315/42925

This collection consists of theses and dissertations produced by graduate students affiliated with the York Centre for Vision Research. These works represent significant contributions to the interdisciplinary field of vision science and have been approved in accordance with the academic standards of their respective graduate programs (including Biology, Digital Media, Electrical Engineering and Computer Science, Interdisciplinary Studies, Kinesiology & Health Science, Philosophy, Physics & Astronomy, Psychology, and others). This collection is managed and deposits authorized by the Coordinator for the Centre.

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Open Access
Anterior Cingulate Cortex Cells Identify Errors of Attentional Control Prior to Prefrontal Disengagement
(2014-07-09) Shen, Chen; Womelsdorf, Thilo
The anterior cingulate cortex (ACC) is implicated in the detection of errors and the allocation of correctional adjustments. However, error detection alone is not sufficient to resolve and prevent future mistakes since errors can occur in various ways, subsequently requiring different adjustments. I therefore investigated whether the ACC tracks specific processing states that give rise to errors in order to identify which specific processing aspects need readjustment. To do this, my lab recorded from cells in the prefrontal cortex (PFC) of macaques while they were performing a selective-attention task that elicited three types of error. My study provides support for the functional role of the ACC in performance monitoring and specifying correctional adjustments through the tracking of specific sources of erroneous task outcomes.
Open Access
Measuring Memory in an Alzheimer's Treatment Trial Using a Visual Search Task
(2015-01-26) Dragan, Michelle; Hoffman, Kari
Alzheimer’s Disease (AD) is characterized by episodic memory deficits attributed to damage to the hippocampal formation. AD therapies specifically targeting hippocampal function may be best evaluated through the use of selective hippocampal tasks. I used a nonverbal hippocampal-dependent target-in-scene detection task to determine if task performance shows age-related decline and/or AD-related impairments. Participants located objects (‘targets’) that appeared/disappeared in flickering natural scenes, yielding faster search times for remembered targets than for forgotten ones. AD patients took longer and required more fixations to detect targets, indicating impaired memory. Furthermore, the AD and aged populations exhibited slower pupillary responses. As part of a clinical trial, I next asked whether deep-brain stimulation of the extended hippocampal circuit would modify memory performance in patients with early AD. The double-blind treatment trial is still underway, thus treatment efficacy is yet to be evaluated, however, trial participants showed a measurable, progressive memory impairment in this task.
Open Access
Transcranial Magnetic Stimulation of Early Visual Cortex During Transsaccadic Integration of Object Features
(2015-08-28) Malik, Pankhuri; Crawford, John Douglas
Visual information is integrated across saccades to maintain a continuous spatiotemporal representation of the world. This study investigated the role of early visual cortex (EVC) in trans-saccadic integration using functional magnetic resonance imaging guided repetitive transcranial magnetic stimulation (rTMS) protocol. Triple-pulse rTMS was applied over left and right EVC during the fixation task (participants maintained gaze), and saccade task (participants made an eye movement that either maintained or reversed the visual quadrant of the test stimulus). rTMS had no effect when 1) fixation was maintained, 2) saccades kept the stimulus in the same visual quadrant, or 3) quadrant corresponding to the first Gabor patch was stimulated. However, rTMS affected performance (relative to opposite EVC rTMS) when saccades brought the remembered visual stimulus into the magnetically stimulated quadrant. This effect increased with saccade amplitude. These results show that EVC is involved in the memory and ‘remapping’ of visual features across saccades.
Open Access
Reinforcement Learning Describes the Computational and Neural Processes Underlying Flexible Learning of Values and Attentional Selection
(2015-12-16) Balcarras, Matthew Dwight; Womelsdorf, Thilo
Attention and learning are cognitive control processes that are closely related. This thesis investigates this inter-relatedness by using computational models to describe the mechanisms that are shared between these processes. Computational models describe the transformation of stimuli to observable variables (behaviour) and contain the latent mechanisms that affect this transformation. Here, I captured these mechanisms with the reinforcement learning (RL) framework applied in two different task contexts and three different projects to show 1) how attentional selection of stimuli involves the learning of values for stimuli, 2) how the learning of stimulus values is influenced by previously learned rules, and 3) how explorations of value-related mechanisms in the brain benefit from using intracranial EEG to investigate the strength of oscillatory activity in ventromedial prefrontal cortex. In the first project, the RL framework is applied to a feature-based attention task that required macaques to learn the value of stimulus features while ignoring non-relevant information. By comparing different RL schemes I found that trial-by-trial covert attentional selections were best predicted by a model that only represents expected values for the task relevant feature dimension. In the second project, I explore mechanisms of stimulus-feature value learning in humans in order to understand the influence of learned rules for the flexible, on-going learning of expected values. I test the hypothesis that naive subjects will show enhanced learning of feature specific reward associations by switching to the use of an abstract rule that associates stimuli by feature type. I found that two-thirds of subjects (n=22/32) exhibited behaviour that was best fit by a ‘flexible-rule-selection’ model. Low-frequency oscillatory activity in frontal cortex has been associated with cognitive control and integrative brain functions, however, the relationship between expected values for stimuli and band-limited, rhythmic neural activity in the human brain is largely unknown. In the third project, I used intracranial electrocorticography (ECoG) in a proof-of-principle study to reveal spectral power signatures in vmPFC related to the expected values of stimuli predicted by a RL model for a single human subject.
Open Access
Decoding Gating Properties of the Pannexin1 Channel: ATP Release and pH Sensitivity and the Potential Role in Health and Disease
(2015-12-16) Whyte-Fagundes, Paige Alexandra; Zoidl, Georg R.
Panx1 is implicated in disorders including epilepsy and ischemia, with roles in important physiological processes including learning, memory and sensory function. In sensory systems, ATP release and purinergic signaling is considered the most important function of Panx1. Here, the function in the olfactory epithelium was investigated using Panx1 knock out mice. Functional analysis in vivo confirmed a role in olfaction suggesting that Panx1 is one of several alternative ATP release pathways. Since epileptic and ischemic events cause extracellular pH changes, the role of Panx1 in pH sensing was explored next. In a cell model Panx1 showed pH dependent channel gating properties. Site directed mutagenesis and high throughput dye uptake tests revealed a conserved domain of the protein as a pH sensor. Further, the critical role of a single histidine residue in this domain was determined. In summary, these studies demonstrate the role of Panx1 in ATP release and pH sensing.
Open Access
Theta-Gamma Coordination Between Anterior Cingulate and Prefrontal Cortex Indexes Correct Attention Shifts
(2015-12-16) Voloh, Benjamin; Womelsdorf, Thilo
Anterior cingulate and prefrontal cortex (ACC/PFC) are believed to coordinate activity to flexibly prioritize the processing of goal-relevant over irrelevant information. This between-area coordination may be realized by common low frequency excitability changes synchronizing segregated high-frequency activations. This coordination hypothesis was tested by recording in macaque ACC/PFC during the covert use of attention cues. There were robust increases of 5-10Hz (theta) to 35-55Hz (gamma) phase-amplitude correlation between ACC and PFC during successful attention shifts but not unsuccessful ones. Cortical sites providing theta phases (1) showed a prominent cue induced phase reset, (2) were more likely in ACC than PFC, and (3) hosted neurons with burst firing events that synchronized to distant gamma activity. These findings suggest that inter-areal theta-gamma correlations could follow mechanistically from a cue-triggered reactivation of rule-memory that synchronizes theta across ACC/PFC.
Open Access
The Role of the Cytoskeleton in the Modulation of the Connexin36 Nexus in N2a Cells
(2015-12-16) Brown, Cherie Alicia; Zoidl, Georg R.
We tested the hypothesis that the interaction of Cx36 with the cytoskeleton is necessary to achieve synaptic plasticity in neurons. In living cells, BioID and FRAP technology was used to demonstrate binding of Cx36 to actin and tubulin. Wild-type and mutant proteins, together with pharmacological blockers or TAT peptides were used to characterize the interaction. Major results of this study are that rCx36 interacts primarily with the neuronal βIII-tubulin isoform to regulate the trafficking and aggregation of connexons at the GJP. Amino acid Lys279 in the CTB domain is critical for this interaction. A potential actin-binding site in the CLB domain of rCx36 was identified, with actin mainly serving as an anchor to stabilize connexons. During a simulation of plasticity in vitro, GJPs became more stable; we attribute this to interactions with the cytoskeleton and associating proteins. We conclude that cytoskeletal-dependent interaction is required to modulate the strength of Cx36 synapses.
Open Access
Abnormal Brain Connectivity in the Primary Visual Pathway in Human Albinism
(2016-09-20) Grigorian, Anahit; Schneider, Keith A.
In albinism, the ipsilateral projection of retinal axons is significantly reduced, and most fibres project contralaterally. The retina and optic chiasm have been proposed as sites for misrouting. The number of lateral geniculate nucleus (LGN) relay neurons has been linked to LGN volume, suggesting a correlation between LGN size and the number of tracts traveling through the optic radiation (OR) to the primary visual cortex (V1). Using diffusion data and both deterministic and probabilistic tractography, we studied differences in OR between albinism and controls. Statistical analyses measured white matter integrity in areas corresponding to the OR, as well as LGN to V1 connectivity. Results revealed reduced white matter integrity and connectivity in the OR region in albinism compared to controls, suggesting altered structural development. Previous reports of smaller LGN and the altered thalamo-cortical connectivity reported here demonstrate the effect of misrouting on structural organization of the visual pathway in albinism.
Open Access
Neural Mechanisms of Transsaccadic Integration of Visual Features
(2016-09-20) Baltaretu, Bianca-Ruxandra; Crawford, John Douglas
This thesis explores the neural mechanisms of transsaccadic integration of visual features. In the study, I investigated the cortical correlates of transsaccadic integration of object orientation in multiple reference frames. In a functional MRI adaptation (fMRIa) paradigm, participants viewed sets of two orientation stimuli in each trial and were asked to indicate if the orientations were the same (Repeat condition) or different (Novel condition). Stimuli were presented in one of three spatial conditions: 1) space-fixed, 2) retina-fixed and 3) frame-independent. Results indicate that, in addition to common activation in frontal motor cortical regions in all three spatial conditions, parietal and occipitotemporal regions are active in the space-fixed condition, parietofrontal regions are active in the retina-fixed condition, and parietofrontal and occipitotemporal regions are active in the frame-independent condition. In conclusion, these results indicate that transsaccadic integration involves differential activation of cortical areas, depending on the frame of reference.
Open Access
Spatial Transformations in Frontal Cortex During Memory-Guided Head-Unrestrained Gaze Shifts
(2016-09-20) Sajad, Amirsaman; Crawford, John Douglas
We constantly orient our line of sight (i.e., gaze) to external objects in our environment. One of the central questions in sensorimotor neuroscience concerns how visual input (registered on retina) is transformed into appropriate signals that drive gaze shift, comprised of coordinated movement of the eyes and the head. In this dissertation I investigated the function of a node in the frontal cortex, known as the frontal eye field (FEF) by investigating the spatial transformations that occur within this structure. FEF is implicated as a key node in gaze control and part of the working memory network. I recorded the activity of single FEF neurons in head-unrestrained monkeys as they performed a simple memory-guided gaze task which required delayed gaze shifts (by a few hundred milliseconds) towards remembered visual stimuli. By utilizing an elaborate analysis method which fits spatial models to neuronal response fields, I identified the spatial code embedded in neuronal activity related to vision (visual response), memory (delay response), and gaze shift (movement response). First (Chapter 2), spatial transformations that occur within the FEF were identified by comparing spatial codes in visual and movement responses. I showed eye-centered dominance in both neuronal responses (and excluded head- and space-centered coding); however, whereas the visual response encoded target position, the movement response encoded the position of the imminent gaze shift (and not its independent eye and head components), and this was observed even within single neurons. In Chapter 3, I characterized the time-course for this target-to-gaze transition by identifying the spatial code during the intervening delay period. The results from this study highlighted two major transitions within the FEF: a gradual transition during the visual-delay-movement extent of delay-responsive neurons, followed by a discrete transition between delay-responsive neurons and pre-saccadic neurons that exclusively fire around the time of gaze movement. These results show that the FEF is involved in memory-based transformations in gaze control; but instead of encoding specific movement parameters (eye and head) it encodes the desired gaze endpoint. The representations of the movement goal are subject to noise and this noise accumulates at different stages related to different mechanisms.
Open Access
Computational Study of Multisensory Gaze-Shift Planning
(2016-11-25) Daemi, Mehdi; Crawford, John Douglas
In response to appearance of multimodal events in the environment, we often make a gaze-shift in order to focus the attention and gather more information. Planning such a gaze-shift involves three stages: 1) to determine the spatial location for the gaze-shift, 2) to find out the time to initiate the gaze-shift, 3) to work out a coordinated eye-head motion to execute the gaze-shift. There have been a large number of experimental investigations to inquire the nature of multisensory and oculomotor information processing in any of these three levels separately. Here in this thesis, we approach this problem as a single executive program and propose computational models for them in a unified framework. The first spatial problem is viewed as inferring the cause of cross-modal stimuli, whether or not they originate from a common source (chapter 2). We propose an evidence-accumulation decision-making framework, and introduce a spatiotemporal similarity measure as the criterion to choose to integrate the multimodal information or not. The variability of report of sameness, observed in experiments, is replicated as functions of the spatial and temporal patterns of target presentations. To solve the second temporal problem, a model is built upon the first decision-making structure (chapter 3). We introduce an accumulative measure of confidence on the chosen causal structure, as the criterion for initiation of action. We propose that gaze-shift is implemented when this confidence measure reaches a threshold. The experimentally observed variability of reaction time is simulated as functions of spatiotemporal and reliability features of the cross-modal stimuli. The third motor problem is considered to be solved downstream of the two first networks (chapter 4). We propose a kinematic strategy that coordinates eye-in-head and head-on-shoulder movements, in both spatial and temporal dimensions, in order to shift the line of sight towards the inferred position of the goal. The variabilities in contributions of eyes and head movements to gaze-shift are modeled as functions of the retinal error and the initial orientations of eyes and head. The three models should be viewed as parts of a single executive program that integrates perceptual and motor processing across time and space.
Open Access
The Effects of Common Fate Grouping on Suprathresold Depth Estimates
(2016-11-25) Marianovski, Michael; Wilcox, Laurie M.
When two vertical lines are perceived to form the boundaries of a common object, observers underestimate their separation in depth. This disruption in perceived depth depends directly on the perceived grouping via closure of the resultant figure. Here I tested if this effect generalises to motion based grouping cues, specifically common fate. Stimuli were presented on a mirror stereoscope and an on screen ruler was used to record depth magnitude estimates. It was found that depth estimates were accurate over a range of suprathreshold disparities, for both static and moving stimuli. Attempts to strengthen the grouping cues had no impact on depth magnitude estimates. This was true even when a more complex biological motion stimulus was used. These results show that previously reported reductions in perceived depth are not generalizable to grouping via common motion. It appears that this phenomenon only occurs when the spatial layout suggests a common object.
Open Access
Peripheral and Central Auditory Processing in People With Absolute Pitch
(2016-11-25) Mcketton, Larissa A.; Schneider, Keith A.
Absolute pitch (AP) is a rare ability that is defined by being able to name musical pitches without a reference standard. This ability has been of interest to researchers studying music cognition and the processing of pitch information because it is very rarely expressed and raises questions about developmental interactions between biological predispositions and musical training. This dissertation focuses mainly on the peripheral and central neural substrates and is divided into seven chapters. The first chapter reviews the anatomy, function, and frequency resolution of the auditory peripheral and central nervous system. It includes background information pertaining to the origins of AP and describes inconsistencies reported throughout a number of studies that characterize AP emergence. Chapter two details a series of peripheral experiments on twenty AP and thirty-three control subjects recruited for testing at two locations. The goal was to test whether frequency resolution differences could be resolved at the level of the cochlea within both groups as a potential correlate for the genesis of AP. Chapter three details two behavioural tests that were administered to assess the smallest frequency difference that AP musicians could resolve and to test how well they could detect melodic mistuning excerpts compared to non-AP musicians and controls without musical experience. Both AP musicians and non-AP musicians did significantly better in both tests compared to non-musicians. However, there were no differences between the AP and non-AP musician groups. Chapter four details a functional MRI study that measured frequency tuning in the cortex using a population receptive field (pRF) model that estimates preferred frequency bandwidth in each voxel. This method was also tested in auditory subcortical nuclei such as the inferior colliculus and medial geniculate nucleus. Chapter five reports the neuro-anatomical correlates of musicianship and AP using structural MRI. Here we investigated cortical thickness and volume differences among the three groups and found a number of regions differed significantly. Cortical thickness was significantly greater in the left Heschls gyrus (an area that acts as a central hub for auditory processing) in AP musicians compared to non-AP musicians and non-musicians. AP and non-AP musicians also exhibited increased cortical thickness and volume throughout their cortex and subcortex. In line with previous studies, AP musicians showed decreased cortical thickness and volume in frontal regions such as the pars opercularis part of the inferior frontal gyrus. Chapter six reports the neuro-anatomical correlates of musicianship and AP using diffusion tensor imaging (DTI) to measure connectivity and white matter structural integrity in regions associated with audition and language processing. Tracts connecting language processing regions were reduced in volume in AP musicians compared to their non-AP counterparts. Chapter seven includes the general discussion, which integrates the findings and results from the five experiments. Our findings indicate that the sharpness of frequency tuning did not differ in either peripheral or central auditory processing stages among AP and non-AP groups. This implies that AP possessors do not encode or represent auditory frequency any differently than other groups, from the periphery through auditory cortex; instead, the neural substrate of their abilities must lie elsewhere. The automatic and working memory independent categorization abilities in AP may reflect more refined efficiency in local but not global functional connectivity.
Open Access
Investigating Visual to Auditory Crossmodal Compensation in a Model For Acute Blindness
(2017-07-26) Savija, Nevena; DeSouza, Joseph
This study examined neural integration of the sensory modalities of vision and hearing. The objective is to investigate whether an effect of cross-modal compensation of visual to auditory networks in human participants occurs with the deprivation of visual input. This model for acute blindness had a novel design that attempted to imitate true blindness. The experiment involved 10 participants wearing opaque contact lenses that blocked visual feedback for a total of five hours. The duration of the total experiment was approximately eight hours, and involved seven sessions. The overall accuracy across time did not improve in blind individuals (p = 0.586), however, there was a significant finding in speaker accuracy (p<0.000), and a significant interaction between session and speaker (p=0.004). Reaction time generated a main effect of session (p<0.000) and a significant main effect of speaker (p<0.000), but no significant interaction between session and speaker with respect to reaction time.
Open Access
The Influence of Alpha7 and Alpha4 Beta2 Nicotinic Receptor Agonists on Feature Based Reversal Learning in Macaque Monkeys
(2018-03-01) Azimi, Marzyeh; Womelsdorf, Thilo
Selective and non-selective nicotinic agonists are associated with improvements in higher order cognitive functions. However, the effects of selectively activating nicotinic sub-receptors on attention and learning are not well understood. In my project, I used two agonists selective for alpha7 (7) and alpha4-beta2 (42) nicotinic sub-receptors to test the effects of selective nicotinic activation on performance in a feature-based reversal learning task in non-human primate subjects. Overall, results showed that selective activation of nicotinic receptors led to improvements in different aspects of the task which were time and dose dependent: the optimal dose of 7 agonist improved performance accuracy and sped up learning of reversals in reward contingency, when drug plasma concentration was at its peak. In comparison, the best dose of 42 agonist reduced susceptibility to distraction. These findings are an important first step to identify the nicotinergic neuromodulatory mechanisms of attention and learning functions in the primate brain.
Open Access
The Impact of Object-Based Grouping on Perceived Depth Magnitude
(2018-03-01) Sudhama, Aishwarya Rajalakshmi; Wilcox, Laurie
The amount of depth perceived between two vertical lines is markedly reduced when those lines are connected. Previously, this effect has been shown to be related to perceptual grouping of elements to form an object. The aim of the experiments reported here is to evaluate the generalizability of this phenomenon, to better understand its role in perception of depth from disparity in natural stimuli. I found that depth estimates were not affected by configuration over a range of suprathreshold disparities, in the presence of additional, reliable cues to depth. Taken together, these results show that previously reported reduction in perceived depth from perceptual grouping is restricted to specific viewing conditions and stimuli. Moreover, the effect is modulated by several factors including the presence or absence of orientation disparity, and the availability and consistency of other depth cues.
Open Access
Neural Processes Underlying the Flexible Control and Learning of Attentional Selection
(2018-05-28) Oemisch, Mariann; Womelsdorf, Thilo
In every-day life we are usually surrounded by a plethora of stimuli, of which only some may be relevant to us at a given moment in time. The dynamic interaction between internal factors, such as our previous experience and current goals, and external factors, such as salient sensory stimulation, determine where, how and what we attend to in our environment. This dissertation investigated some of the neural mechanisms that underlie successful goal-directed behavior in two conditions 1. when attention was actively cued to a target stimulus, and 2. when the attentional target had to be actively and repeatedly learned, in macaque monkeys and in humans. In Chapter 2, I investigated inter-areal spiketrain correlations in neuron pairs across the fronto-cingulate cortex when macaque monkeys are cued to shift their attention to one of two target stimuli. I found that neuron pairs in anterior cingulate cortex (ACC) and dorsal prefrontal cortex (PFC) with similar spatial preferences correlate their spiketrains at the time when attention needs to be actively shifted, suggesting that the flexible interaction between these two areas may support successful covert attention shifts. In Chapter 3, I show that when the attentional target stimulus needs to be repeatedly learned and is defined by only one of several stimulus features, neurons in macaque frontal and striatal regions encode prediction error signals that carry specific information about the stimulus feature that was selected in the preceding choice. These signals may be involved in identifying those synapses that require updating to allow flexible adjustments in goal-directed behavior. In Chapter 4, I found that when humans must repeatedly learn the identity of an attentional target, a human event-related potential over visual cortex that is thought to index attentional target selection, selectively decreases after successful learning, in particular for the distracting stimulus, and selectively increases for the target stimulus following negative feedback during learning. Overall, this dissertation provides novel insights into some of the complex neural mechanisms that support flexible control and learning of attention across brain regions of the human and non-human primate brain.
Open Access
Eye-Head-Hand Coordination During Visually Guided Reaches in Head-Unrestrained Macaques
(2020-05-11) Arora, Harbandhan Kaur; Crawford, John Douglas
Our goal was to determine if reaching influences eye-head coordination (and vice versa) in Rhesus macaques. Eye, head, and hand motion were recorded in two animals using search coil and touch screen technology, respectively. Animals were seated in a customized chair which allowed unencumbered head motion and reaching in depth. In the reach condition, animals were trained to touch a central LED at waist level while maintaining central gaze and were then rewarded if they touched a target appearing at one of 15 locations. In other variants, initial hand or gaze position were varied in the horizontal plane. In similar control tasks, animals were rewarded for gaze accuracy. In the reach task, animals made eye-head gaze shifts toward the target followed by reaches that were accompanied by prolonged head motion toward the target. This resulted in significantly larger velocities and final ranges of head position compared with the gaze control.
Open Access
The Impact of Monocular Self-Occlusions on Depth Perception
(2020-11-13) Au, Domenic Chun On; Wilcox, Laurie M
Depth perceived from two-object arrangement half-occlusions has been shown to depend on the occluded regions size and texture properties. However, monocular regions also result from single-object self-occlusions where the monocular region sizes and texture properties could influence its perceived shape. In a series of experiments, I assessed sensitivity to monocular texture changes, perceived object coherence, and occlusion size under geometrically valid and invalid conditions. Monocular texture changes had little impact on perceived depth when binocular disparity was present in the stimulus suggesting that disparity is extrapolated across monocular regions to determine object shape. There was considerable tolerance to invalid occlusion arrangements when monocular regions were perceived as part of a coherent object. Furthermore, quantitative depth from self-occlusions do not follow minimum depth constraint predictions. My experiments show that interpretation of self-occlusions depends on their context; heuristics used to extract depth information from monocular regions are contingent on foreground/background segmentation.
Open Access
Roles of Calmodulin and a N-Methyl-D-Aspartate Receptor - Pannexin-1 Signaling Complex in Connexin-36 Plasticity
(2021-03-08) Siu, Ryan Chi-Fung; Zoidl, Georg R.
The synergic actions of calcium, calmodulin, and calmodulin kinase II are the central mechanism for synaptic plasticity. Until the last two decades, chemical synapses through N-methyl D-aspartate receptors were thought to be the only synapse that demonstrates plasticity. Our research has shown previously that electrical synapses use CaM/CaMKII interaction in a similar Ca2+-dependent process for plasticity. New evidence suggests that other channels and kinases have modulatory roles in the whole mechanism. This thesis explores the contributions and roles that different kinases, receptors, and channels have on electrical synaptic plasticity. The over-arching hypothesis is that the activation of N-methyl-D-aspartate receptors and pannexin1 channels drives Ca2+ change for physiological signaling of Cx36 plasticity. Here, I introduce a novel modality for CaM electrical synapse regulation and unify the electro-chemical transmission mechanism. I demonstrate that both N-methyl-D-aspartate receptors and pannexin1 channels influence the plasticity at the gap junction nexus. These findings opened up new avenues to expand on mechanisms for synaptic plasticity.

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