Between the beginning of time and the end of it, there's relatively only an eyeblink, and without life there's no one to see that eyeblink or remember it.
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And these groups appear in what is, in geological terms, an eyeblink.
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This quasar appeared to have shut down in less than 10 years — a cosmic eyeblink.
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One day, she's a sentient adorable lump, and an eyeblink later she's speaking in full sentences.
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As with all these questions, I don't even have to ponder before I answer with an eyeblink—it's lonesome, of course.
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You feel like a badass as you wade your way through groups of baddies, dropping entire squads in an eyeblink whenever you slow things down.
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Urban should be a known quantity to most, but his gruff delivery and ability to go from sweet to scary in an eyeblink make him a powerful presence in every scene.
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But given the topsy-turvy nature of Hollywood creative development, where projects can disappear in an eyeblink, this casting news is a good sign that HBO is moving forward with the prequel.
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Tasha: We've griped that this season seems really rushed; we've given up on travel time, and characters seem to teleport all over Westeros, and conversations that really should take some time, like Tyrion and Jaime's post-Tywin reunion, rush by in an eyeblink.
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Electrophysiological recording studies of cerebellar cortex have helped to better understand the role that PCs play in the eyeblink CR learning process. McCormick and Thompson (1984b) recorded PC activity during eyeblink training and found cell populations that discharged in a pattern apparently related the behavioral CR, while other PC populations discharged in patterns that coincided with either presentation of the CS or US. Similar results were found by Berthier and Moore (1986) with single unit recording of PCs in lobule HVI. They found that populations of neurons fire in relation to various aspects of eyeblink training, including CS and US presentation and CR execution. (Berthier and Moore, 1986; Gould and Steinmetz, 1996).
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Eyeblink conditioning (EBC) is a form of classical conditioning that has been used extensively to study neural structures and mechanisms that underlie learning and memory. The procedure is relatively simple and usually consists of pairing an auditory or visual stimulus (the conditioned stimulus (CS)) with an eyeblink-eliciting unconditioned stimulus (US) (e.g. a mild puff of air to the cornea or a mild shock). Naïve organisms initially produce a reflexive, unconditioned response (UR) (e.g.
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Time-dependent reorganization of the brain components underlying memory retention in trace eyeblink conditioning. J. Neurosci., 23:9896–9905.Squire, L. R., Stark, C. E. L., & R. E. Clark (2004).
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The most common physiological response measured to gauge FPS response in humans is eyeblink, or the reflexive act of blinking. Currently, the most widely accepted/used means with which to measure the eyeblink reflex is by using a technology called electromyographic recording (EMG). EMG provides eyeblink rate data by measuring and recording activity of the eyelid muscles using two electrodes. In order to obtain an optimal reading, the person's skin must be cleaned, dried, and covered with a thin layer of electrode gel in only the spots where the measures will be taken; one electrode is placed in the center of the person's forehead above the nose, and two recording electrodes are placed directly underneath the eye, approximately two centimeters apart.
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Fear-potentiated startle (FPS) has been utilized as a psychophysiological index of fear reaction in both animals and humans. FPS is most often assessed through the magnitude of the eyeblink startle reflex, which can be measured by electromyography. This eyeblink reflex is an automatic defensive reaction to an abrupt elicitor, making it an objective indicator of fear. Typical FPS paradigms involve bursts of noise or abrupt flashes of light transmitted while an individual attends to a set of stimuli.
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Attwell, Rahman, and Yeo (2001) discovered similar disruption of with HVI inactivation. They infused the AMPA receptor antagonist CNQX into HVI during acquisition training and found that CNQX- infused rabbits did not learn the eyeblink CR. However, post-acquisition CNQX infusions did not affect retention. These results are perplexing, given that animals ultimately learned the eyeblink CR in all other cerebellar cortical lesion and inactivation studies. One reason why this effect is so strong may be that Attwell et al.
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Taken together, results from lesion, inactivation, and neural recording studies seem to demonstrate that the cerebellar cortex is not essential for basic eyeblink CR learning or retention, but that significant contributions from cortex underlie normal learning.
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Professor Richard F. Thompson and his colleagues initially identified the cerebellum as the essential structure for learning and executing eyeblink CRs. Some scientists think that the interposed nucleus is the site critical to learning, retaining, and executing the conditioning blink response.
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Recordings of multiple-unit neuronal activity from rabbit INP during eyeblink conditioning have been possible with chronic electrode implants, and have revealed a population of cells that discharge prior to the initiation of the learned eyeblink CR and fire in a pattern of increased response frequency that predicted and modeled the temporal form of the behavioral CR (McCormick et al., 1981; 1982; 1983; Thompson, 1983; 1986; Foy et al., 1984; McCormick & Thompson, 1984a; b; Berthier & Moore, 1990; Gould & Steinmetz, 1996). Similar results were found in the rat INP (Freeman & Nicholson, 2000; Stanton & Freemen, 2000; Rogers et al.
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Mice took significantly longer to produce CRs, and the timing and gain of the response were distorted (Chen et al., 1996). Therefore, although eyeblink CR learning deficits are associated with cerebellar cortex lesions, the structure does not appear, ultimately, to be essential for CR learning or retention.
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Two areas of cortex that are known to be involved in eyeblink conditioning are lobule HVI (Lavond et al., 1987; Lavond and Steinmetz, 1989; Yeo and Hardiman, 1992) and the anterior lobe ((ANT) Garcia, Steele, and Mauk, 1999). The importance of cerebellar cortex in EBC, relative to INP, is a matter of debate in the scientific community.
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This suggests that increased excitability may function as a mechanism for memory storage. In eyeblink conditioning in rabbits, nonsynaptic changes occurred throughout the dorsal hippocampus. This indicates that although excitability changes alone are not enough to explain memory storage processes, nonsynaptic plasticity might be a storage mechanism for phases of memory limited by time. Nonsynaptic changes influence other types of plasticity involved with memory.
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Experiments have revealed that nonsynaptic changes take place during conditional learning. Woody et al. demonstrated that eyeblink conditioning (EBC), a form of classical conditioning for studying neural structures and mechanisms underlying learning and memory, in a cat is associated with increased excitability and input in the neurons in sensorimotor cortical areas and in the facial nucleus. It was observed that increasing excitability from classical conditioning continued after the response stopped.
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The trigeminal nucleus also sends efferent projections to the inferior olive (IO), and this represents the US pathway for EBC. The critical region of the IO for eyeblink conditioning is the dorsal accessory olive (Brodal, 1981), and climbing fibers (CF) from this region send information about the US to the cerebellum (Brodal, Walberg & Hoddevik, 1975; Thompson, 1989). Climbing fibers ultimately project to both the deep cerebellar nuclei and Purkinje cells (PCs) in the cerebellar cortex.
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These behaviors include eyeblink conditioning, motor learning in the vestibulo-ocular reflex, and birdsong. Research on Aplysia californica, the sea slug, has yielded detailed knowledge of the cellular mechanisms of a simple form of learning. A type of motor learning occurs during operation of a brain-computer interface. For example, Mikhail Lebedev, Miguel Nicolelis and their colleagues recently demonstrated cortical plasticity that resulted in incorporation of an external actuator controlled through a brain-machine interface into the subject's neural representation.
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Alternative sites of synaptic plasticity critical to EBC have been posited to exist downstream from the cerebellum. Some proposed loci include the red nucleus (Tsukahara, Oda, and Notsu, 1981), the trigeminal nucleus and associated structures (Desmond & Moore, 1983), or the facial motor nucleus (Woody et al., 1974). All of these structures have been ruled out as potential sites of plasticity critical to learning the eyeblink CR (Krupa, Thompson, and Thompson, 1993; Clark and Lavond, 1996; Krupa, Weng, and Thompson, 1996).
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Several studies have attempted to assess the role of the cerebellar cortex in eyeblink CR learning, and early studies focused on large aspiration lesions of cerebellar cortex. Lavond and Steinmetz (1989) completely removed lobules HVI/HVIIa and significant portions of ANT, sparing INP, and found significant acquisition deficits. Compared to controls, lesioned animals took seven times longer to reach learning criterion. Significant percentages of CRs were eventually reached by the cortically-lesioned animals, but the CRs were low in amplitude and poorly timed.
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Persons with right-wing views had greater skin conductance response, indicating greater sympathetic nervous system response, to threatening images than those with left-wing views in one study. There was no difference for positive or neutral images. Holding right-wing views was also associated with a stronger startle reflex as measured by strength of eyeblink in response to unexpected noise. In an fMRI study published in Social Neuroscience, three different patterns of brain activation were found to correlate with individualism, conservatism, and radicalism.
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169 Usually the onset of the startle response is a startle reflex reaction. The startle reflex is a brainstem reflectory reaction (reflex) that serves to protect vulnerable parts, such as the back of the neck (whole-body startle) and the eyes (eyeblink) and facilitates escape from sudden stimuli. It is found across the lifespan of many species. A variety of responses may occur because of individual's emotional state, body posture, cited preparation for execution of a motor task, cited or other activities.
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Using this system, she discovered that the forward steps of the ataxic Purkinje cell degeneration (pcd) mice are normal, but instead they have difficulty coordinating their movement. The tracking system dissects movement defects quantitatively to more precisely pinpoint phenotypic defects. Her group recently uncovered an unexpected link between movement and learning. While examining a type of learning called "eyeblink conditioning" in mice, Carey and her team noticed that the time to condition was highly variable between individuals and difficult to track.
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In addition, larger amplitude responses were recorded during PrL stimulation, further supporting that the pathways were separate. The M2 pathway is shown in red, originating in the pre-motor cortex. The PrL pathway is shown in purple, originating in the medial prefrontal cortex The PrL cortex and M2 cortex are involved in actions such as eyeblink conditioning, action initiation and termination, conflict-monitoring between automatic and voluntary behavioral strategies, attention, and direct and indirect eye movement control. They are also involved in even higher cognitive functions such as stimulus-outcome encoding and automatization of recurrent actions.
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Recently, similar stimulus- and response-related PC activity has been found in ANT (Green and Steinmetz, 2005). Finally, electrophysiological recordings of PCs in HVI and ANT have revealed a difference in the overall population responses of PCs. The majority of PCs show excitatory patterns of activity during eyeblink conditioning in HVI (Berthier and Moore, 1986; Gould and Steinmetz, 1996; Katz and Steinmetz, 1997), and inhibitory patterns of activity in ANT (Green and Steinmetz, 2005). In a single unit recording study where the individual Purkinje cells were shown to be located in the area controlling blinks and to receive climbing fibre input on US presentations, only inhibitory responses were found.
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Eyeblink FPS response is typically gauged by presenting participants with pleasant and unpleasant (as well as neutral) emotionally evocative stimuli, paired with a loud noise or a flash of bright lights. The presented stimuli can be replaced by having participants imagine emotionally evocative stimuli of pleasant, unpleasant, and neutral natures. FPS response is typically most exaggerated in response to emotionally unpleasant stimuli, followed by pleasant and then neutral stimuli, in members of the general population. In addition, FPS response in research concerning fear conditioning (and extinction of a conditioned aversion to a previously neutral stimulus) is also commonly examined; such studies will present noise or light startle probes with unpleasant stimuli to condition the FPS to occur in the presence of that stimuli.
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The acoustic startle reflex response to a sound when sensing anxiety sweat was larger than when sensing exercise-induced sweat, as measured by electromyography analysis of the orbital muscle, which is responsible for the eyeblink component. This showed for the first time that fear chemosignals can modulate the startle reflex in humans without emotional mediation; fear chemosignals primed the recipient's "defensive behavior" prior to the subjects' conscious attention on the acoustic startle reflex level. In analogy to the social buffering of rats and honeybees in response to chemosignals, induction of empathy by "smelling anxiety" of another person has been found in humans. A study from 2013 provided brain imaging evidence that human responses to fear chemosignals may be gender-specific.
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In 2008, Ross applied for the James Randi Educational Foundation's One Million Dollar Paranormal Challenge with the claim that energy from his eyes could cause a speaker, receiving no other input, to sound a tone. In 2010, Ross published experimental data that supports his scientific hypothesis that the eyes emit energy that can be captured and measured in the Anthropology of Consciousness, a journal of the American Anthropological Association.Wiley Interscience During correspondence with Steven Novella of The Skeptic's Guide to the Universe, he conceded that the equipment he was using was a biofeedback machine attached to his laptop, and that the laptop was responding in a well-understood way to an eye blink. However, he claimed that he could still send energy beams out of his eyes, and was working on modifying the software to ignore an eyeblink.
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In a pioneering study by Gilbert and Thach from 1977, Purkinje cells from monkeys learning a reaching task showed increased complex spike activity—which is known to reliably indicate activity of the cell's climbing fiber input—during periods when performance was poor. Several studies of motor learning in cats observed complex spike activity when there was a mismatch between an intended movement and the movement that was actually executed. Studies of the vestibulo–ocular reflex (which stabilizes the visual image on the retina when the head turns) found that climbing fiber activity indicated "retinal slip", although not in a very straightforward way. One of the most extensively studied cerebellar learning tasks is the eyeblink conditioning paradigm, in which a neutral conditioned stimulus (CS) such as a tone or a light is repeatedly paired with an unconditioned stimulus (US), such as an air puff, that elicits a blink response.
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Allan Wagner Allan R. Wagner (6 January 1934 - 28 September 2018) was an American experimental psychologist and learning theorist, whose work focused upon the basic determinants of associative learning and habituation. He co- authored the influential Rescorla–Wagner model of Pavlovian conditioning (1972) as well as the Standard Operating Procedures or "Sometimes Opponent Process" (SOP) theory of associative learning (1981), the Affective Extension of SOP (AESOP, 1989) and the Replaced Elements Model (REM) of configural representation (2001, 2008). His research involved extensive study of the conditioned eyeblink response of the rabbit, of which he was one of the initial investigators (1964). Wagner received his Ph.D. from the University of Iowa in 1959, under Kenneth W. Spence, and he was on the faculty of Yale University until his death, serving as Chair of the Department of Psychology from 1983–1989, Chair of the Department of Philosophy from 1991–1993, Director of the Division of the Social Sciences from 1992–1998, and in his last years the James Rowland Angell Professor Emeritus of Psychology.
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