An Anatomical Interface between Memory and Oculomotor Systems

2016 ◽  
Vol 28 (11) ◽  
pp. 1772-1783 ◽  
Author(s):  
Kelly Shen ◽  
Gleb Bezgin ◽  
Rajajee Selvam ◽  
Anthony R. McIntosh ◽  
Jennifer D. Ryan
Keyword(s):  
Oculomotor System ◽  
Neural Circuitry ◽  
Data Driven ◽  
Oculomotor Control ◽  
Anatomical Connectivity ◽  
Gaze Patterns ◽  
Directed Information ◽  
Posterior Parietal ◽  
Neuropsychological Evidence ◽  
To Receive

Visual behavior is guided by memories from prior experience and knowledge of the visual scene. The hippocampal system (HC), in particular, has been implicated in the guidance of saccades: Amnesic patients, following damage to the HC, exhibit selective deficits in their gaze patterns. However, the neural circuitry by which mnemonic representations influence the oculomotor system remains unknown. We used a data-driven, network-based approach on directed anatomical connectivity from the macaque brain to reveal an extensive set of polysnaptic pathways spanning the extrastriate, posterior parietal and prefrontal cortices that potentially mediate the exchange of information between the memory and visuo-oculomotor systems. We additionally show how the potential for directed information flow from the hippocampus to oculomotor control areas is exceptionally high. In particular, the dorsolateral pFC and FEF—regions known to be responsible for the cognitive control of saccades—are topologically well positioned to receive information from the hippocampus. Together with neuropsychological evidence of altered gaze patterns following damage to the hippocampus, our findings suggest that a reconsideration of hippocampal involvement in oculomotor guidance is needed.

scholarly journals A DATA-DRIVEN APPROACH TO USER-EXPERIENCE-FOCUSED MODEL-BASED ROADMAPPING FOR NEW PRODUCT PLANNING

2021 ◽  
Vol 1 ◽  
pp. 61-70
Author(s):  
Ilia Iuskevich ◽  
Andreas-Makoto Hein ◽  
Kahina Amokrane-Ferka ◽  
Abdelkrim Doufene ◽  
Marija Jankovic
Keyword(s):  
New Product Development ◽  
User Experience ◽  
Planning Process ◽  
New Product ◽  
Data Driven ◽  
User Needs ◽  
User Testing ◽  
Model Based ◽  
Data Driven Approach ◽  
To Receive

AbstractUser experience (UX) focused business needs to survive and plan its new product development (NPD) activities in a highly turbulent environment. The latter is a function of volatile UX and technology trends, competition, unpredictable events, and user needs uncertainty. To address this problem, the concept of design roadmapping has been proposed in the literature. It was argued that tools built on the idea of design roadmapping have to be very flexible and data-driven (i.e., be able to receive feedback from users in an iterative manner). At the same time, a model-based approach to roadmapping has emerged, promising to achieve such flexibility. In this work, we propose to incorporate design roadmapping to model-based roadmapping and integrate it with various user testing approaches into a single tool to support a flexible data-driven NPD planning process.

Oculomotor Control of Primary Eye Position Discriminates Between Translation and Tilt

1999 ◽  
Vol 81 (1) ◽  
pp. 394-398 ◽  
Author(s):  
Bernhard J. M. Hess ◽  
Dora E. Angelaki
Keyword(s):  
Dynamic Control ◽  
Linear Acceleration ◽  
Oculomotor System ◽  
Oculomotor Control ◽  
Eye Position ◽  
Axis Orientation ◽  
Fast Phase ◽  
Ocular Reflex ◽  
Vestibulo Ocular Reflex ◽  
Head Rotations

Hess, Bernhard J. M. and Dora E. Angelaki. Oculomotor control of primary eye position discriminates between translation and tilt. J. Neurophysiol. 81: 394–398, 1999. We have previously shown that fast phase axis orientation and primary eye position in rhesus monkeys are dynamically controlled by otolith signals during head rotations that involve a reorientation of the head relative to gravity. Because of the inherent ambiguity associated with primary otolith afferent coding of linear accelerations during head translation and tilts, a similar organization might also underlie the vestibulo-ocular reflex (VOR) during translation. The ability of the oculomotor system to correctly distinguish translational accelerations from gravity in the dynamic control of primary eye position has been investigated here by comparing the eye movements elicited by sinusoidal lateral and fore-aft oscillations (0.5 Hz ± 40 cm, equivalent to ± 0.4 g) with those during yaw rotations (180°/s) about a vertically tilted axis (23.6°). We found a significant modulation of primary eye position as a function of linear acceleration (gravity) during rotation but not during lateral and fore-aft translation. This modulation was enhanced during the initial phase of rotation when there was concomitant semicircular canal input. These findings suggest that control of primary eye position and fast phase axis orientation in the VOR are based on central vestibular mechanisms that discriminate between gravity and translational head acceleration.

scholarly journals Unrestricted eye movements strengthen causal connectivity from hippocampal to oculomotor regions during scene construction

2021 ◽  
Author(s):  
Natalia Ladyka-Wojcik ◽  
Zhong-Xu Liu ◽  
Jennifer D. Ryan
Keyword(s):  
Eye Movements ◽  
Visual Processing ◽  
Oculomotor System ◽  
Visual Input ◽  
Causal Modeling ◽  
Oculomotor Control ◽  
Visual Stream ◽  
Functional Connections ◽  
Free Viewing ◽  
Scene Construction

Scene construction is a key component of memory recall, navigation, and future imagining, and relies on the medial temporal lobes (MTL). A parallel body of work suggests that eye movements may enable the imagination and construction of scenes, even in the absence of external visual input. There are vast structural and functional connections between regions of the MTL and those of the oculomotor system. However, the directionality of connections between the MTL and oculomotor control regions, and how it relates to scene construction, has not been studied directly in human neuroimaging. In the current study, we used dynamic causal modeling (DCM) to investigate this relationship at a mechanistic level using a scene construction task in which participants' eye movements were either restricted (fixed-viewing) or unrestricted (free-viewing). By omitting external visual input, and by contrasting free- versus fixed- viewing, the directionality of neural connectivity during scene construction could be determined. As opposed to when eye movements were restricted, allowing free viewing during construction of scenes strengthened top-down connections from the MTL to the frontal eye fields, and to lower-level cortical visual processing regions, suppressed bottom-up connections along the visual stream, and enhanced vividness of the constructed scenes. Taken together, these findings provide novel, non-invasive evidence for the causal architecture between the MTL memory system and oculomotor system associated with constructing vivid mental representations of scenes.

scholarly journals Electrical microstimulation evokes saccades in posterior parietal cortex of common marmosets

2019 ◽  
Vol 122 (4) ◽  
pp. 1765-1776 ◽  
Author(s):  
Maryam Ghahremani ◽  
Kevin D. Johnston ◽  
Liya Ma ◽  
Lauren K. Hayrynen ◽  
Stefan Everling
Keyword(s):  
Eye Movements ◽  
Parietal Cortex ◽  
Posterior Parietal Cortex ◽  
Common Marmoset ◽  
Primate Species ◽  
Oculomotor Control ◽  
Electrical Microstimulation ◽  
Cortical Areas ◽  
Posterior Parietal ◽  
The Common

The common marmoset ( Callithrix jacchus) is a small-bodied New World primate increasing in prominence as a model animal for neuroscience research. The lissencephalic cortex of this primate species provides substantial advantages for the application of electrophysiological techniques such as high-density and laminar recordings, which have the capacity to advance our understanding of local and laminar cortical circuits and their roles in cognitive and motor functions. This is particularly the case with respect to the oculomotor system, as critical cortical areas of this network such as the frontal eye fields (FEF) and lateral intraparietal area (LIP) lie deep within sulci in macaques. Studies of cytoarchitecture and connectivity have established putative homologies between cortical oculomotor fields in marmoset and macaque, but physiological investigations of these areas, particularly in awake marmosets, have yet to be carried out. Here we addressed this gap by probing the function of posterior parietal cortex of the common marmoset with electrical microstimulation. We implanted two animals with 32-channel Utah arrays at the location of the putative area LIP and applied microstimulation while they viewed a video display and made untrained eye movements. Similar to previous studies in macaques, stimulation evoked fixed-vector and goal-directed saccades, staircase saccades, and eyeblinks. These data demonstrate that area LIP of the marmoset plays a role in the regulation of eye movements, provide additional evidence that this area is homologous with that of the macaque, and further establish the marmoset as a valuable model for neurophysiological investigations of oculomotor and cognitive control. NEW & NOTEWORTHY The macaque monkey has been the preeminent model for investigations of oculomotor control, but studies of cortical areas are limited, as many of these areas are buried within sulci in this species. Here we applied electrical microstimulation to the putative area LIP of the lissencephalic cortex of awake marmosets. Similar to the macaque, microstimulation evoked contralateral saccades from this area, supporting the marmoset as a valuable model for studies of oculomotor control.

The Transfusion Services Committee—Responsibilities and Response to Adverse Transfusion Events

Hematology ◽  
2005 ◽  
Vol 2005 (1) ◽  
pp. 483-490 ◽  
Author(s):  
Ira A. Shulman ◽  
Sunita Saxena
Keyword(s):  
Performance Improvement ◽  
Review Process ◽  
High Volume ◽  
The United States ◽  
Adverse Outcomes ◽  
Data Driven ◽  
Medicaid Program ◽  
And Performance ◽  
To Receive

Abstract Healthcare institutions in the United States must review blood transfusion practices and adverse outcomes in order to receive payments from the Centers for Medicare/Medicaid program, but it is not required for a specific committee to be assigned to oversee the review process. Regardless of the group or individuals responsible, the review process must include a program of quality assessment and performance improvement that is ongoing, hospital-wide, and data-driven, reflects the complexity of the hospital’s organization and services, and involves all hospital departments and services (including those contracted). To be most effective, the performance improvement activity should be prioritized around high-risk, high-volume activities and/or in problem-prone areas. Even if a hospital elects not to receive payments from Medicare, it must still comply with applicable sections of the Code of Federal Regulations pertaining to transfusion services such as the follow up of adverse outcomes of transfusion.

scholarly journals Mapping the neural circuitry of predator fear in the nonhuman primate

2020 ◽  
Author(s):  
Quentin Montardy ◽  
William C. Kwan ◽  
Inaki C. Mundinano ◽  
Dylan M. Fox ◽  
Liping Wang ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Neural Circuitry ◽  
Ventromedial Hypothalamus ◽  
Brain Network ◽  
Retrograde Tracing ◽  
Anatomical Connectivity ◽  
Core Node ◽  
Marmoset Monkey ◽  
System A ◽  
Learned Fear

AbstractIn rodents, innate and learned fear of predators depends on the medial hypothalamic defensive system, a conserved brain network that lies downstream of the amygdala and promotes avoidance via projections to the periaqueductal gray. Whether this network is involved in primate fear remains unknown. To address this, we provoked flight responses to a predator (moving snake) in the marmoset monkey under laboratory conditions. We combined c-Fos immunolabeling and anterograde/retrograde tracing to map the functional connectivity of the ventromedial hypothalamus, a core node in the medial hypothalamic defensive system. Our findings demonstrate that the ventromedial hypothalamus is recruited by predator exposure in primates and that anatomical connectivity of the rodent and primate medial hypothalamic defensive system are highly conserved.

An Oculomotor Test to Measure Alcohol Impairment

1994 ◽  
Vol 78 (2) ◽  
pp. 603-610
Author(s):  
Andris Freivalds ◽  
Ken Horii
Keyword(s):  
Test Scores ◽  
Interindividual Variability ◽  
Quantitative Measure ◽  
Drunk Driving ◽  
Oculomotor System ◽  
Individual Characteristics ◽  
Oculomotor Control ◽  
Alcohol Impairment

Drunk driving continues to be one of the nation's most serious safety problems. On the premise that oculomotor control provides a quantitative measure that is very sensitive to alcohol impairment, an oculomotor test previously developed as a portable hand-held Viewmaster viewer with specially designed grating patterns as images was used to stress the oculomotor system. Test scores decreased with increased alcohol impairment along with a large dependence on individual lateral phoria scores. Unfortunately, there was a large amount of interindividual variability, which may limit use of the test for the population at large unless other individual characteristics are included.

scholarly journals Single-unit activity in marmoset posterior parietal cortex in a gap saccade task

2020 ◽  
Vol 123 (3) ◽  
pp. 896-911 ◽  
Author(s):  
Liya Ma ◽  
Janahan Selvanayagam ◽  
Maryam Ghahremani ◽  
Lauren K. Hayrynen ◽  
Kevin D. Johnston ◽  
...  
Keyword(s):  
Parietal Cortex ◽  
Unit Activity ◽  
Single Unit ◽  
Posterior Parietal Cortex ◽  
Common Marmoset ◽  
Gap Effect ◽  
Oculomotor Control ◽  
Single Unit Activity ◽  
Primate Model ◽  
Posterior Parietal

Abnormal saccadic eye movements can serve as biomarkers for patients with several neuropsychiatric disorders. The common marmoset ( Callithrix jacchus) is becoming increasingly popular as a nonhuman primate model to investigate the cortical mechanisms of saccadic control. Recently, our group demonstrated that microstimulation in the posterior parietal cortex (PPC) of marmosets elicits contralateral saccades. Here we recorded single-unit activity in the PPC of the same two marmosets using chronic microelectrode arrays while the monkeys performed a saccadic task with gap trials (target onset lagged fixation point offset by 200 ms) interleaved with step trials (fixation point disappeared when the peripheral target appeared). Both marmosets showed a gap effect, shorter saccadic reaction times (SRTs) in gap vs. step trials. On average, stronger gap-period responses across the entire neuronal population preceded shorter SRTs on trials with contralateral targets although this correlation was stronger among the 15% “gap neurons,” which responded significantly during the gap. We also found 39% “target neurons” with significant saccadic target-related responses, which were stronger in gap trials and correlated with the SRTs better than the remaining neurons. Compared with saccades with relatively long SRTs, short-SRT saccades were preceded by both stronger gap-related and target-related responses in all PPC neurons, regardless of whether such response reached significance. Our findings suggest that the PPC in the marmoset contains an area that is involved in the modulation of saccadic preparation. NEW & NOTEWORTHY As a primate model in systems neuroscience, the marmoset is a great complement to the macaque monkey because of its unique advantages. To identify oculomotor networks in the marmoset, we recorded from the marmoset posterior parietal cortex during a saccadic task and found single-unit activities consistent with a role in saccadic modulation. This finding supports the marmoset as a valuable model for studying oculomotor control.

scholarly journals Separate Representations of Target and Timing Cue Locations in the Supplementary Eye Fields

2009 ◽  
Vol 101 (1) ◽  
pp. 448-459 ◽  
Author(s):  
Michael Campos ◽  
Boris Breznen ◽  
Richard A. Andersen
Keyword(s):  
Eye Movement ◽  
Brain Area ◽  
Target Position ◽  
Oculomotor System ◽  
Small Population ◽  
Oculomotor Control ◽  
Brain Areas ◽  
Saccade Task ◽  
Supplementary Eye Fields ◽  
The Brain

When different stimuli indicate where and when to make an eye movement, the brain areas involved in oculomotor control must selectively plan an eye movement to the stimulus that encodes the target position and also encode the information available from the timing cue. This could pose a challenge to the oculomotor system since the representation of the timing stimulus location in one brain area might be interpreted by downstream neurons as a competing motor plan. Evidence from diverse sources has suggested that the supplementary eye fields (SEF) play an important role in behavioral timing, so we recorded single-unit activity from SEF to characterize how target and timing cues are encoded in this region. Two monkeys performed a variant of the memory-guided saccade task, in which a timing stimulus was presented at a randomly chosen eccentric location. Many spatially tuned SEF neurons encoded only the location of the target and not the timing stimulus, whereas several other SEF neurons encoded the location of the timing stimulus and not the target. The SEF population therefore encoded the location of each stimulus with largely distinct neuronal subpopulations. For comparison, we recorded a small population of lateral intraparietal (LIP) neurons in the same task. We found that most LIP neurons that encoded the location of the target also encoded the location of the timing stimulus after its presentation, but selectively encoded the intended eye movement plan in advance of saccade initiation. These results suggest that SEF, by conditionally encoding the location of instructional stimuli depending on their meaning, can help identify which movement plan represented in other oculomotor structures, such as LIP, should be selected for the next eye movement.

Eye movements elicited by electrical stimulation of area PG in the monkey

1991 ◽  
Vol 65 (6) ◽  
pp. 1243-1253 ◽  
Author(s):  
D. D. Kurylo ◽  
A. A. Skavenski
Keyword(s):  
Electrical Stimulation ◽  
Eye Movements ◽  
Parietal Cortex ◽  
Posterior Parietal Cortex ◽  
Eye Position ◽  
Low Velocity ◽  
Posterior Parietal ◽  
Rostral Region ◽  
To Receive ◽  
Stimulation Of

1. Eye positions of monkeys were tracked while low-current electrical stimulation was delivered to area PG of the posterior parietal cortex. Stimulation was delivered while monkeys were in darkness, while they were in a dimly illuminated room, or while they actively fixated on small lamps to receive a liquid reward. 2. Resulting eye movements fell into one of three categories, depending roughly on the area stimulated. Stimulation of caudal regions generally resulted in saccades that were of approximately equivalent amplitudes and directions. When more rostral areas were stimulated, saccades were generally produced that directed the eyes toward roughly the same position in the head. Distributed throughout all regions were sites for which elicited saccades did not fall clearly into either of these coordinate bases. Stimulation of lateral areas produced low-velocity eye movements that were directed ipsilaterally from the stimulated hemisphere. 3. Stimulation made while monkeys fixated on target lamps produced saccades with more variability and less amplitude than those produced while monkeys were in darkness. Low-velocity eye movements could only be elicited while monkeys were in darkness. 4. Craniocentric saccades typically brought the eyes to within a 10-20 degrees area, and saccades could not be produced when the initial eye position was near this area. Craniocentric saccades were always greater than 5 degrees in amplitude. 5. It is concluded that area PG is organized into at least two zones that differ in the way by which they code saccades. A caudal region codes saccades in a way similar to that found in the frontal cortex and superior colliculus of primates. A rostral region codes saccades in a craniocentric manner, although it is restricted only to gross redirection of gaze without the accuracy monkeys are capable of using in directing their eyes.

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