Short article: Effects of interlimb practice on coding and learning of movement sequences

An interlimb practice paradigm was designed to determine the role that visual–spatial (Cartesian) and motor (joint angles, activation patterns) coordinates play in the coding and learning of complex movement sequences. Participants practised a 16-element movement sequence by moving a lever to sequentially presented targets with one limb on Day 1 and the contralateral limb on Day 2. Practice involved the same sequence with either the same visual–spatial or motor coordinates on the two days. A unilateral practice condition (control) was also tested where both coordinate systems were changed but the same limb was used. Retention tests were conducted on Day 3. Regardless of the order in which the limbs were used during practice, results indicated that keeping the visual–spatial coordinates the same during acquisition resulted in superior retention. This provides strong evidence that the visual–spatial code plays a dominant role in complex movement sequences, and this code is represented in an effector-independent manner.

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The effect of how to perform movement sequences on absolute and relative timing transfer

Psicológica Journal ◽

10.2478/psicolj-2019-0001 ◽

2019 ◽

Vol 40 (1) ◽

pp. 1-25 ◽

Cited By ~ 1

Author(s):

Amin Ghamari ◽

Mehdi Sohrabi ◽

Alireza Saberi Kakhki

Keyword(s):

Movement Time ◽

Relative Timing ◽

Movement Sequences ◽

Visual Spatial ◽

Significant Difference ◽

Movement Sequence ◽

Spatial Coordinates ◽

Timing Properties ◽

Better Than ◽

The Way

AbstractDepending on the difficulty of the task in terms of movement duration and the number of elements forming the sequence, recent research has shown that movement sequences are coded in visual-spatial coordinates or motor coordinates. An interesting question that arises is how a specific manner of performance without a change in such functional difficulties affects the representation of movement sequences. Accordingly, the present study investigated how the way in which a movement sequence is performed affects the transfer of timing properties (absolute and relative timing) from the practised to unpractised hand under mirror (same motor commands as those used in practice) and non-mirror (the same visual-spatial coordinates as those present during practice) conditions in two experiments each with segment movement time goals that were arranged differently. The study showed that after a limited amount of practice, the pattern of results obtained for relative timing differed between the two experiments. In the first experiment, there was no difference between retention and non-mirror transfer, but performance on these tasks was significantly better than that for mirror transfer, whereas in the second experiment, there was no difference between the mirror and non-mirror transfer. For total errors, no significant difference was found between the retention and transfer tests in both experiments. It was concluded that the way in which a sequence is performed could affect the representation of the task and the transfer of relative timing, while absolute timing could purposefully be maintained if necessary.

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Role of cAMP in Double Switch of Glucagon Secretion

Cells ◽

10.3390/cells10040896 ◽

2021 ◽

Vol 10 (4) ◽

pp. 896

Author(s):

Jan Zmazek ◽

Vladimir Grubelnik ◽

Rene Markovič ◽

Marko Marhl

Keyword(s):

Glucose Metabolism ◽

Signaling Pathway ◽

Cell Model ◽

Dominant Role ◽

Glucagon Secretion ◽

Camp Signaling ◽

Independent Manner ◽

Metabolic Switch ◽

Camp Signaling Pathway ◽

Double Switch

Glucose metabolism plays a crucial role in modulating glucagon secretion in pancreatic alpha cells. However, the downstream effects of glucose metabolism and the activated signaling pathways influencing glucagon granule exocytosis are still obscure. We developed a computational alpha cell model, implementing metabolic pathways of glucose and free fatty acids (FFA) catabolism and an intrinsically activated cAMP signaling pathway. According to the model predictions, increased catabolic activity is able to suppress the cAMP signaling pathway, reducing exocytosis in a Ca2+-dependent and Ca2+ independent manner. The effect is synergistic to the pathway involving ATP-dependent closure of KATP channels and consequent reduction of Ca2+. We analyze the contribution of each pathway to glucagon secretion and show that both play decisive roles, providing a kind of “secure double switch”. The cAMP-driven signaling switch plays a dominant role, while the ATP-driven metabolic switch is less favored. The ratio is approximately 60:40, according to the most recent experimental evidence.

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Simulation of Complex Movement Sequences in the Product Development of a Car Manufacturer

10.4271/2003-01-2194 ◽

2003 ◽

Cited By ~ 1

Author(s):

Stefan Rigel ◽

Ernst Assmann ◽

Heiner Bubb

Keyword(s):

Product Development ◽

Movement Sequences ◽

Complex Movement

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Demonstration of artificial visual percepts generated through thalamic microstimulation

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.0608563104 ◽

2007 ◽

Vol 104 (18) ◽

pp. 7670-7675 ◽

Cited By ~ 99

Author(s):

John S. Pezaris ◽

R. Clay Reid

Keyword(s):

Lateral Geniculate Nucleus ◽

Visual Prosthesis ◽

Dorsal Lateral Geniculate Nucleus ◽

Visual Response ◽

Prosthetic Device ◽

Visual Spatial ◽

Lateral Geniculate ◽

Spatial Coordinates ◽

Saccade Task ◽

Dorsal Lateral Geniculate

Electrical stimulation of the visual system might serve as the foundation for a prosthetic device for the blind. We examined whether microstimulation of the dorsal lateral geniculate nucleus of the thalamus can generate localized visual percepts in alert monkeys. To assess electrically generated percepts, an eye-movement task was used with targets presented on a computer screen (optically) or through microstimulation of the lateral geniculate nucleus (electrically). Saccades (fast, direct eye movements) made to electrical targets were comparable to saccades made to optical targets. Gaze locations for electrical targets were well predicted by measured visual response maps of cells at the electrode tips. With two electrodes, two distinct targets could be independently created. A sequential saccade task verified that electrical targets were processed not in motor coordinates, but in visual spatial coordinates. Microstimulation produced predictable visual percepts, showing that this technique may be useful for a visual prosthesis.

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ON THE REPRESENTATION, LEARNING AND TRANSFER OF SPATIO-TEMPORAL MOVEMENT CHARACTERISTICS

International Journal of Humanoid Robotics ◽

10.1142/s0219843604000320 ◽

2004 ◽

Vol 01 (04) ◽

pp. 613-636 ◽

Cited By ~ 33

Author(s):

WINFRIED ILG ◽

GÖKHAN H. BAKIR ◽

JOHANNES MEZGER ◽

MARTIN A. GIESE

Keyword(s):

Representation Learning ◽

Movement Sequences ◽

Movement Trajectories ◽

Movement Characteristics ◽

Human Movements ◽

Complex Sequences ◽

Movement Representation ◽

Spatio Temporal ◽

Morphable Models ◽

Complex Movement

In this paper we present a learning-based approach for the modeling of complex movement sequences. Based on the method of Spatio-Temporal Morphable Models (STMMs) we derive a hierarchical algorithm that, in a first step, identifies automatically movement elements in movement sequences based on a coarse spatio-temporal description, and in a second step models these movement primitives by approximation through linear combinations of learned example movement trajectories. We describe the different steps of the algorithm and show how it can be applied for modeling and synthesis of complex sequences of human movements that contain movement elements with a variable style. The proposed method is demonstrated on different applications of movement representation relevant for imitation learning of movement styles in humanoid robotics.

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Age-related effects in interlimb practice on coding complex movement sequences

Human Movement Science ◽

10.1016/j.humov.2010.11.003 ◽

2011 ◽

Vol 30 (3) ◽

pp. 459-474 ◽

Cited By ~ 17

Author(s):

Stefan Panzer ◽

Nicole Gruetzmacher ◽

Udo Fries ◽

Melanie Krueger ◽

Charles H. Shea

Keyword(s):

Movement Sequences ◽

Age Related ◽

Complex Movement

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Basal ganglia neural mechanisms of natural movement sequences

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y04-061 ◽

2004 ◽

Vol 82 (8-9) ◽

pp. 732-739 ◽

Cited By ~ 55

Author(s):

J Wayne Aldridge ◽

Kent C Berridge ◽

Alyssa R Rosen

Keyword(s):

Basal Ganglia ◽

Neural Mechanisms ◽

Sequential Patterns ◽

Striatal Neurons ◽

Warm Up ◽

Movement Sequences ◽

Natural Movement ◽

Baseline Levels ◽

Instinctive Behavior ◽

Complex Movement

Natural rodent grooming and other instinctive behavior serves as a natural model of complex movement sequences. Rodent grooming has syntactic (rule-driven) sequences and more random movement patterns. Both incorporate the same movements—only the serial structure differs. Recordings of neural activity in the dorsolateral striatum and the substantia nigra pars reticulata indicate preferential activation during syntactic sequences over more random sequences. Neurons that are responsive during syntactic grooming sequences are often unresponsive or have reverse activation profiles during kinematically similar movements that occur in flexible or random grooming sequences. Few neurons could be categorized as strictly movement related—instead they were activated only in the context of particular sequential patterns of movements. Particular sequential patterns included "syntactic chain" grooming sequences of paw, head, and body movements and also "warm-up" sequences, which consist of head and body/limb movements that precede locomotion after a period of quiet resting (Golani 1992). Activation during warm-up was less intense and less frequent than during grooming sequences, but both sequences activated neurons above baseline levels, and the same neurons sometimes responded to both sequences. The fact that striatal neurons code 2 natural sequences which are made up of different constituent movements suggests that the basal ganglia may have a generalized role in sequence control. The basal ganglia are modulated by the context of the sequence and may play an executive function in the complex natural patterns of sequenced behaviour.Key words: movement, basal ganglia, striatum, movement sequences, sensorimotor behaviour.

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Subunit-dependent and independent rules of AMPA receptor trafficking during long-term depression in hippocampal neurons

10.1101/2020.11.12.379867 ◽

2020 ◽

Author(s):

Shinji Matsuda ◽

Michisuke Yuzaki

Keyword(s):

Hippocampal Neurons ◽

Protein Complexes ◽

Dominant Role ◽

Adaptor Protein ◽

Long Term Potentiation ◽

Proximal Region ◽

Phosphorylation Sites ◽

Independent Manner ◽

Ampar Trafficking

ABSTRACTLong-term potentiation (LTP) and depression (LTD) of excitatory neurotransmission are believed to be the neuronal basis of learning and memory. Both processes are primarily mediated by neuronal activity-induced transport of postsynaptic AMPA-type glutamate receptors (AMPARs). While AMPAR subunits and their specific phosphorylation sites mediate differential AMPAR trafficking, LTP and LTD could also occur in a subunit-independent manner. Thus, it remains unclear whether and how, certain AMPAR subunits with phosphorylation sites are preferentially recruited to or removed from synapses during LTP and LTD. Here, we show that phosphorylation of the membrane-proximal region (MPR), which only occurs in GluA1 AMPAR subunits, mediates the subunit-dependent endosomal transport of AMPARs during LTD. AP-2 and AP-3, adaptor protein complexes necessary for clathrin-mediated endocytosis and late endosomal/lysosomal trafficking, respectively, are reported to be recruited to AMPARs by binding to the AMPAR auxiliary subunit, stargazin (STG), in an AMPAR subunit-independent manner. However, the association of AP-3, but not AP-2, with STG was indirectly inhibited by the phosphomimetic mutation in the MPR of GluA1. Thus, although AMPARs containing the phosphomimetic mutation at the MPR of GluA1 were endocytosed by a LTD-inducing stimulus, they were quickly recycled back to the cell surface in hippocampal neurons. These results could explain how the phosphorylation status of GluA1-MPR plays a dominant role in subunit-independent STG-mediated AMPAR trafficking during LTD.

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