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Journal of the Experimental Analysis of... Oct 1959
Topics: Discrimination Learning; Learning; Reinforcement, Psychology
PubMed: 13851480
DOI: 10.1901/jeab.1959.2-293 -
Current Biology : CB Jun 1998Monkeys trained to distinguish touch stimuli that 'flutter' with different frequencies can similarly distinguish electrical stimulation of the somatosensory cortex... (Review)
Review
Monkeys trained to distinguish touch stimuli that 'flutter' with different frequencies can similarly distinguish electrical stimulation of the somatosensory cortex according to its frequency; the implication is that the electrically-evoked patterns of cortical activity cause flutter sensations similar to those induced by touch.
Topics: Animals; Discrimination Learning; Electric Stimulation; Evoked Potentials, Somatosensory; Macaca mulatta; Neurons; Physical Stimulation; Somatosensory Cortex; Touch
PubMed: 9637911
DOI: 10.1016/s0960-9822(98)70265-9 -
Scientific Reports Dec 2016Accurate discrimination of the intensity and spatial location of nociceptive stimuli is essential to guide appropriate behaviour. The ability to discriminate the...
Accurate discrimination of the intensity and spatial location of nociceptive stimuli is essential to guide appropriate behaviour. The ability to discriminate the attributes of sensory stimuli is continuously refined by practice, even throughout adulthood - a phenomenon called perceptual learning. In the visual domain, perceptual learning to discriminate one of the features that define a visual stimulus (e.g., its orientation) can transfer to a different feature of the same stimulus (e.g., its contrast). Here, we performed two experiments on 48 volunteers to characterize perceptual learning in nociception, which has been rarely studied. We investigated whether learning to discriminate either the intensity or the location of nociceptive stimuli (1) occurs during practice and is subsequently maintained, (2) requires feedback on performance, and (3) transfers to the other, unpractised stimulus feature. First, we found clear evidence that perceptual learning in discriminating both the intensity and the location of nociceptive stimuli occurs, and is maintained for at least 3 hours after practice. Second, learning occurs only when feedback is provided during practice. Finally, learning is largely confined to the feature for which feedback was provided. We discuss these effects in a predictive coding framework, and consider implications for future studies.
Topics: Adult; Discrimination Learning; Female; Formative Feedback; Healthy Volunteers; Humans; Male; Nociception; Photic Stimulation; Space Perception; Spatial Navigation; Visual Perception; Young Adult
PubMed: 27996022
DOI: 10.1038/srep39104 -
Journal of Vision Apr 2004Almost nothing is known about brightness discrimination in animals and how this ability relates to their lifestyles. As arrhythmic visual generalists, three dogs, a...
Almost nothing is known about brightness discrimination in animals and how this ability relates to their lifestyles. As arrhythmic visual generalists, three dogs, a German shepherd and two Belgian shepherds, were tested on their ability to discriminate brightness using a series of 30 shades of grey varying from white to black. The dogs were trained to discriminate between different shades of grey in a simultaneous two-choice situation. Weber's law can be correlated to their ability to discriminate brightness differences with a calculated Weber fraction of 0.22 for the German shepherd and 0.27 for the Belgian shepherds. Thus brightness discrimination in dogs is about 2 times worse than in humans, a diurnal species.
Topics: Animals; Discrimination Learning; Dogs; Light; Male; Visual Perception
PubMed: 15086313
DOI: 10.1167/4.3.10 -
The Journal of Neuroscience : the... Sep 2012Our sensory experiences over a range of different timescales shape our perception of the environment. Two particularly striking short-term forms of plasticity with...
Our sensory experiences over a range of different timescales shape our perception of the environment. Two particularly striking short-term forms of plasticity with manifestly different time courses and perceptual consequences are those caused by visual adaptation and perceptual learning. Although conventionally treated as distinct forms of experience-dependent plasticity, their neural mechanisms and perceptual consequences have become increasingly blurred, raising the possibility that they might interact. To optimize our chances of finding a functionally meaningful interaction between learning and adaptation, we examined in humans the perceptual consequences of learning a fine discrimination task while adapting the neurons that carry most information for performing this task. Learning improved discriminative accuracy to a level that ultimately surpassed that in an unadapted state. This remarkable improvement came at a price: adapting directions that before learning had little effect elevated discrimination thresholds afterward. The improvements in discriminative accuracy grew quickly and surpassed unadapted levels within the first few training sessions, whereas the deterioration in discriminative accuracy had a different time course. This learned reconfiguration of adapted discriminative accuracy occurred without a concomitant change to the characteristic perceptual biases induced by adaptation, suggesting that the system was still in an adapted state. Our results point to a functionally meaningful push-pull interaction between learning and adaptation in which a gain in sensitivity in one adapted state is balanced by a loss of sensitivity in other adapted states.
Topics: Adaptation, Physiological; Adolescent; Adult; Discrimination Learning; Discrimination, Psychological; Female; Humans; Male; Motion Perception; Photic Stimulation; Psychometrics; Sensory Thresholds; Time Factors; Visual Perception; Young Adult
PubMed: 23015451
DOI: 10.1523/JNEUROSCI.1363-12.2012 -
Journal of Vision Jul 2019The staircase method has been widely used in measuring perceptual learning. Recently, Zhao, Lesmes, and Lu (2017, 2019) developed the quick Change Detection (qCD) method...
The staircase method has been widely used in measuring perceptual learning. Recently, Zhao, Lesmes, and Lu (2017, 2019) developed the quick Change Detection (qCD) method and applied it to measure the trial-by-trial time course of dark adaptation. In the current study, we conducted two simulations to evaluate the performance of the 3-down/1-up staircase and qCD methods in measuring perceptual learning in a two-alternative forced-choice task. In Study 1, three observers with different time constants (40, 80, and 160 trials) of an exponential learning curve were simulated. Each simulated observer completed staircases with six step sizes (1%, 5%, 10%, 20%, 30%, and 60%) and a qCD procedure, each starting at five levels (+50%, +25%, 0, -25%, and -50% different from the true threshold in the first trial). We found the following results: Staircases with 1% and 5% step sizes failed to generate more than five reversals half of the time; and the bias and standard deviations of thresholds estimated from the post hoc segment-by-segment qCD analysis were much smaller than those from the staircase method with the other four step sizes. In Study 2, we simulated thresholds in the transfer phases with the same time constants and 50% transfer for each observer in Study 1. We found that the estimated transfer indexes from qCD showed smaller biases and standard deviations than those from the staircase method. In addition, rescoring the simulated data from the staircase method using the Bayesian estimation component of the qCD method resulted in much-improved estimates. We conclude that the qCD method characterizes the time course of perceptual learning and transfer more accurately, precisely, and efficiently than the staircase method, even with the optimal 10% step size.
Topics: Bayes Theorem; Choice Behavior; Dark Adaptation; Discrimination Learning; Humans; Learning Curve; Repetition Priming; Sensory Thresholds
PubMed: 31323664
DOI: 10.1167/19.7.14 -
Psychopharmacology Jun 2016The lowest nicotine threshold "dose" in cigarettes discriminated from a cigarette containing virtually no nicotine may help inform the minimum dose maintaining...
RATIONALE
The lowest nicotine threshold "dose" in cigarettes discriminated from a cigarette containing virtually no nicotine may help inform the minimum dose maintaining dependence.
OBJECTIVES
Spectrum research cigarettes (from NIDA) differing in nicotine content were used to evaluate a procedure to determine discrimination thresholds.
METHODS
Dependent smokers (n = 18; 13 M, 5 F) were tested on ability to discriminate cigarettes with nicotine contents of 11, 5, 2.4, and 1.3 mg/g, one per session, from the "ultralow" cigarette with 0.4 mg/g, after having discriminated 16 mg/g from 0.4 mg/g (all had 9-10 mg "tar"). Exposure to each was limited to 4 puffs/trial. All subjects were abstinent from smoking overnight prior to each session, and the number of sessions was determined by the participant's success in discrimination behavior on >80 % of trials. Subjective perceptions and behavioral choice between cigarettes were also assessed and related to discrimination behavior.
RESULTS
The median threshold was 11 mg/g, but the range was 2.4 to 16 mg/g, suggesting wide variability in discrimination threshold. Compared to the ultralow, puff choice was greater for the subject's threshold dose but only marginal for the subthreshold (next lowest nicotine) cigarette. Threshold and subthreshold also differed on subjective perceptions but not withdrawal relief.
CONCLUSIONS
Under these testing conditions, threshold content for discriminating nicotine via cigarettes may be 11 mg/g or greater for most smokers, but some can discriminate nicotine contents one-half or one-quarter this amount. Further study with other procedures and cigarette exposure amounts may identify systematic differences in nicotine discrimination thresholds.
Topics: Adult; Choice Behavior; Discrimination Learning; Dose-Response Relationship, Drug; Female; Humans; Male; Nicotine; Smoking; Tobacco Products; Young Adult
PubMed: 27037937
DOI: 10.1007/s00213-016-4281-2 -
Journal of Neurophysiology Dec 2020Auditory experience and behavioral training can modify perceptual performance. However, the consequences of temporal perceptual learning for temporal and spectral neural...
Auditory experience and behavioral training can modify perceptual performance. However, the consequences of temporal perceptual learning for temporal and spectral neural processing remain unclear. Specifically, the attributes of neural plasticity that underlie task generalization in behavioral performance remain uncertain. To assess the relationship between behavioral and neural plasticity, we evaluated neuronal temporal processing and spectral tuning in primary auditory cortex (AI) of anesthetized owl monkeys trained to discriminate increases in the envelope frequency (e.g., 4-Hz standard vs. >5-Hz targets) of sinusoidally amplitude-modulated (SAM) 1-kHz or 2-kHz carriers. Behavioral and neuronal performance generalization was evaluated for carriers ranging from 0.5 kHz to 8 kHz. Psychophysical thresholds revealed high SAM discrimination acuity for carriers from one octave below to ∼0.6 octave above the trained carrier frequency. However, generalization of SAM discrimination learning progressively declined for carrier frequencies >0.6 octave above the trained carrier frequency. Neural responses in AI showed that SAM discrimination training resulted in ) increases in temporal modulation preference, especially at carriers close to the trained frequency, ) narrowing of spectral tuning for neurons with characteristic frequencies near the trained carrier frequency, potentially limiting spectral generalization of temporal training effects, and ) enhancement of firing-rate contrast for rewarded versus nonrewarded SAM frequencies, providing a potential cue for behavioral temporal discrimination near the trained carrier frequency. Our findings suggest that temporal training at a specific spectral location sharpens local frequency tuning, thus, confining the training effects to a narrow frequency range and limiting generalization of temporal discrimination learning across a wider frequency range. Monkeys' ability to generalize amplitude modulation discrimination to nontrained carriers was limited to one octave below and 0.6 octave above the trained carrier frequency. Asymmetric generalization was paralleled by sharpening in cortical spectral tuning and enhanced firing-rate contrast between rewarded and nonrewarded SAM stimuli at carriers near the trained frequency. The spectral content of the training stimulus specified spectral and temporal plasticity that may provide a neural substrate for limitations in generalization of temporal discrimination learning.
Topics: Animals; Auditory Cortex; Behavior, Animal; Discrimination Learning; Female; Generalization, Psychological; Haplorhini; Neuronal Plasticity; Time Factors
PubMed: 32997564
DOI: 10.1152/jn.00278.2020 -
The Journal of Pharmacology and... Jul 2011Tramadol is an unscheduled atypical analgesic that acts as an agonist at μ-opioid receptors and inhibits monoamine reuptake. Tramadol can suppress opioid withdrawal,... (Comparative Study)
Comparative Study Randomized Controlled Trial
Tramadol is an unscheduled atypical analgesic that acts as an agonist at μ-opioid receptors and inhibits monoamine reuptake. Tramadol can suppress opioid withdrawal, and chronic administration can produce opioid physical dependence; however, diversion and abuse of tramadol is low. The present study further characterized tramadol in a three-choice discrimination procedure. Nondependent volunteers with active stimulant and opioid use (n = 8) participated in this residential laboratory study. Subjects were trained to discriminate between placebo, hydromorphone (8 mg), and methylphenidate (60 mg), and tests of acquisition confirmed that all volunteers could discriminate between the training drugs. The following drug conditions were then tested during discrimination test sessions: placebo, hydromorphone (4 and 8 mg), methylphenidate (30 and 60 mg), and tramadol (50, 100, 200, and 400 mg). In addition to discrimination measures, which included discrete choice, point distribution, and operant responding, subjective and physiological effects were measured for each test condition. Both doses of hydromorphone and methylphenidate were identified as hydromorphone- and methylphenidate-like, respectively. Lower doses of tramadol were generally identified as placebo, with higher doses (200 and 400 mg) identified as hydromorphone, or opioid-like. The highest dose of tramadol increased ratings on the stimulant scale, but was not significantly identified as methylphenidate-like. Tramadol did not significantly increase subjective ratings associated with reinforcement. Taken together, these results extend previous work with tramadol as a potential medication for the treatment of opioid dependence and withdrawal, showing acute doses of tramadol exhibit a profile of effects similar to opioid agonists and may have abuse liability in certain populations.
Topics: Adult; Conditioning, Operant; Discrimination Learning; Double-Blind Method; Humans; Male; Reinforcement Schedule; Tramadol
PubMed: 21467190
DOI: 10.1124/jpet.111.181131 -
Schizophrenia Bulletin Jul 2016Although individuals with schizophrenia show impaired feedback-driven learning on probabilistic reversal learning (PRL) tasks, the specific factors that contribute to...
Although individuals with schizophrenia show impaired feedback-driven learning on probabilistic reversal learning (PRL) tasks, the specific factors that contribute to these deficits remain unknown. Recent work has suggested several potential causes including neurocognitive impairments, clinical symptoms, and specific types of feedback-related errors. To examine this issue, we administered a PRL task to 126 stable schizophrenia outpatients and 72 matched controls, and patients were retested 4 weeks later. The task involved an initial probabilistic discrimination learning phase and subsequent reversal phases in which subjects had to adjust their responses to sudden shifts in the reinforcement contingencies. Patients showed poorer performance than controls for both the initial discrimination and reversal learning phases of the task, and performance overall showed good test-retest reliability among patients. A subgroup analysis of patients (n = 64) and controls (n = 49) with good initial discrimination learning revealed no between-group differences in reversal learning, indicating that the patients who were able to achieve all of the initial probabilistic discriminations were not impaired in reversal learning. Regarding potential contributors to impaired discrimination learning, several factors were associated with poor PRL, including higher levels of neurocognitive impairment, poor learning from both positive and negative feedback, and higher levels of indiscriminate response shifting. The results suggest that poor PRL performance in schizophrenia can be the product of multiple mechanisms.
Topics: Adult; Cognitive Dysfunction; Discrimination Learning; Female; Follow-Up Studies; Humans; Male; Middle Aged; Probability Learning; Reversal Learning; Schizophrenia
PubMed: 26884546
DOI: 10.1093/schbul/sbv226