Animal Learning of Independent and Correlated Events

1978 ◽  
Vol 30 (1) ◽  
pp. 105-111 ◽  
Author(s):  
P. E. Wookey ◽  
R. C. Morris ◽  
R. M. Kirby
Keyword(s):  
Unconditioned Stimulus ◽  
Learned Helplessness ◽  
Present Experiment ◽  
Conditioned Response ◽  
Appetitive Conditioning ◽  
Animal Learning ◽  
Random Presentation ◽  
Attention Theory ◽  
The Us ◽  
Classically Conditioned

Evidence suggests that experience of a truly random presentation of a conditioned and unconditioned stimulus (CS and US) retards subsequent acquisition of a classically conditioned response when the CS and US are paired. In these studies, no events reliably predict the US during the first part of training. The present experiment demonstrated impairment of subsequent appetitive conditioning in rats following a random CS-US presentation, both when another predictive cue is present and when it is absent during this experience. Results are discussed with reference to “general attention” theory, and learned helplessness. However, the data support an interpretation in terms of learning a specific relationship between a particular CS and US.

scholarly journals Reactivation of hedonic but not sensory representations in human emotional learning

2021 ◽  
Author(s):  
Mana R Ehlers ◽  
James H Kryklywy ◽  
Andre O Beukers ◽  
Sarah R Moore ◽  
Forys J Brandon ◽  
...  
Keyword(s):  
Conditioned Stimulus ◽  
Unconditioned Stimulus ◽  
Brain Regions ◽  
Higher Order ◽  
Fmri Data ◽  
Similarity Analysis ◽  
Appetitive Conditioning ◽  
Activation Patterns ◽  
The Us ◽  
Novel Variation

Learning which stimuli in our environment co-occur with painful or pleasurable events is critical for survival. Previous research has established the basic neural and behavioural mechanisms of aversive and appetitive conditioning; however, it is unclear what precisely is learned. Here we examined what aspects of the unconditioned stimulus (US), sensory and hedonic, are transferred to the conditioned stimulus (CS). To decode the content of brain activation patterns elicited during appetitive (soft touch) and aversive (painful touch) conditioning of faces, a novel variation of representational similarity analysis (RSA) based on theoretically driven representational patterns of interest (POIs) was applied to fMRI data. Once face associations were learned through conditioning, globally the CS reactivated US representational patterns showing conditioning dependent reactivation. More specifically, in higher order brain regions, the CS only reactivated hedonic but not sensory aspects of the US, suggesting that affective conditioning primarily carries forward the valence of the experience rather than its sensory origins.

Selective serotonin reuptake inhibition increases noise burst-induced unconditioned and context-conditioned freezing

2018 ◽  
Vol 31 (1) ◽  
pp. 46-51
Author(s):  
S. Melker Hagsäter ◽  
Johan Thorén ◽  
Robert Pettersson ◽  
Elias Eriksson
Keyword(s):  
Unconditioned Stimulus ◽  
Serotonin Reuptake ◽  
Conditioned Response ◽  
Selective Serotonin Reuptake Inhibitors ◽  
Conditioned Fear ◽  
Noise Burst ◽  
Selective Serotonin ◽  
Unconditioned Response ◽  
Acute Administration ◽  
Sprague Dawley

AbstractObjectiveWhereas long-term administration of selective serotonin reuptake inhibitors (SSRIs) is effective for the treatment of anxiety disorders, acute administration of these drugs may exert a paradoxical anxiogenic effect. The aim of the present study was to explore the possible effect of an SSRI in situations of unconditioned or limited conditioned fear.MethodsMale Sprague Dawley rats were administered a single dose of an SSRI, escitalopram, before acquisition or expression of context conditioned fear, where noise bursts were used as the unconditioned stimulus. Freezing was assessed as a measure of unconditioned fear (=the acute response to noise bursts) or conditioned fear (=the response to the context), respectively.ResultsNoise bursts elicited an acute increase in freezing but no robust conditioned response 7 days after exposure. Administration of escitalopram before testing exacerbated the freezing response during presentation of the unconditioned stimulus and also unmasked a conditioned response; in contrast, administration of escitalopram prior to acquisition did not influence the conditioned response.ConclusionThe data suggest that freezing in rats exposed to a stimulus inducing relatively mild fear may be enhanced by acute pretreatment with an SSRI regardless of whether the freezing displayed by the animals is an acute unconditioned response to the stimulus in question or a conditioned response to the same stimulus.

scholarly journals On the role of responses in Pavlovian acquisition

2018 ◽  
Author(s):  
Stefano Ghirlanda ◽  
Magnus Enquist
Keyword(s):  
Unconditioned Stimulus ◽  
Pavlovian Conditioning ◽  
Conditioned Response ◽  
Quantitative Methods ◽  
Eyeblink Conditioning ◽  
Key Pecking ◽  
Lever Pressing

A defining feature of Pavlovian conditioning is that the unconditioned stimulus (US) is delivered whether or not the animal performs a conditioned response (CR). This has lead to the question: Does CR performance play any role in learning? Between the 1930's and 1970's, a consensus emerged that CR acquisition is driven by CS-US experiences, and that CRs play a minimal role, if any. Here we revisit the question and present two new quantitative methods to evaluate whether CRs influence the course of learning. Our results suggest that CRs play an important role in Pavlovian acquisition, in such paradigms as rabbit eyeblink conditioning, pigeon autoshaped key pecking, and rat autoshaped lever pressing and magazine entry.

scholarly journals No Evaluative Conditioning Effects with Briefly Presented Stimuli

2018 ◽  
Author(s):  
Tobias Heycke ◽  
Christoph Stahl
Keyword(s):  
Conditioned Stimulus ◽  
Unconditioned Stimulus ◽  
Visual Stimuli ◽  
Neutral Stimulus ◽  
Evaluative Conditioning ◽  
Visual Modality ◽  
Contingency Awareness ◽  
The Us

Evaluative Conditioning (EC) changes the preference towards a formerly neutral stimulus (Conditioned Stimulus; CS), by pairing it with a valent stimulus (Unconditioned Stimulus; US), in the direction of the valence of the US. When the CS is presented subliminally (i.e., too briefly to be consciously perceived), contingency awareness between CS and US can be ruled out. Hence, EC effects with subliminal CSs would support theories claiming that contingency awareness is not necessary for EC effects to occur. Recent studies reported the absence of EC with briefly presented CSs when both CS and US were presented in the visual modality, even though the CSs were identified at above-chance levels. Challenging this finding, Heycke and colleagues (2017) found some evidence for an EC effect with briefly presented visual stimuli in a cross-modal paradigm with auditory USs, but that study did not assess CS visibility. The present study attempted to replicate this EC effect with different stimuli and a CS visibility check. Overall EC for briefly presented stimuli was absent, and results from the visibility check show that an EC effect with briefly presented CSs was only found, when the CSs were identified at above-chance levels.

scholarly journals Relation between Conditioned Stimulus-Elicit Responses and Unconditioned Response Diminution in Long-Interval Human Heart-Rate Classical Conditioning

2001 ◽  
Vol 4 (1) ◽  
pp. 11-18 ◽  
Author(s):  
José L. Marcos ◽  
Jaime Redondo
Keyword(s):  
Heart Rate ◽  
Classical Conditioning ◽  
Conditioned Response ◽  
Human Heart ◽  
Neutral Stimulus ◽  
Unconditioned Response ◽  
Heart Rate Deceleration ◽  
The Us ◽  
Geometrical Shapes ◽  
Rate Deceleration

Previous research on electrodermal conditioning suggests that the conditioned diminution of the unconditioned response (UR) has an associative basis. The aim of this experiment was to test whether this phenomenon also occurs in heart rate (HR) classical conditioning. For this purpose, a differential classical conditioning was performed. The conditioned stimuli (CSs) were geometrical shapes (the CS+ was a square and the CS− was a triangle) displayed on a computer screen and a burst of white noise was used as unconditioned stimulus (US). For analysis of the conditioned response (CR) components, an interval between CS+ and US of 8 seconds was used. After the acquisition phase, participants were tested using trials with the US preceded either by a CS+, a CS−, or a neutral stimulus (a circle). The results showed conditioned diminution of the UR and suggest that the second heart rate deceleration component (D2) is responsible for the occurrence of this phenomenon.

scholarly journals Development of behavioural automaticity by extended Pavlovian training in an insect

2019 ◽  
Vol 286 (1894) ◽  
pp. 20182132 ◽  
Author(s):  
Makoto Mizunami ◽  
Sho Hirohata ◽  
Ai Sato ◽  
Ryoichi Arai ◽  
Kanta Terao ◽  
...  
Keyword(s):  
Unconditioned Stimulus ◽  
Pavlovian Conditioning ◽  
Conditioned Response ◽  
Instrumental Conditioning ◽  
Outcome Expectancy ◽  
Gryllus Bimaculatus ◽  
Sensory Experiences ◽  
Extended Training ◽  
Major Subject ◽  
And Control

The effect of repetitive training on learned actions has been a major subject in behavioural neuroscience. Many studies of instrumental conditioning in mammals, including humans, suggested that learned actions early in training are goal-driven and controlled by outcome expectancy, but they become more automatic and insensitive to reduction in the value of the outcome after extended training. It was unknown, however, whether the development of value-insensitive behaviour also occurs by extended training of Pavlovian conditioning in any animals. Here we show that crickets Gryllus bimaculatus that had received minimal training to associate an odour with water (unconditioned stimulus, US) did not exhibit conditioned response (CR) to the odour when they were given water until satiation before the test, but those that had received extended training exhibited CR even when they were satiated with water. Further pharmacological experiments suggested that octopamine neurons, the invertebrate counterparts of noradrenaline neurons, mediate US value signals and control execution of CR after minimal training, but the control diminishes with the progress of training and hence the CR becomes insensitive to US devaluation. The results suggest that repetitive sensory experiences can lead to a change from a goal-driven response to a more automatic one in crickets.

Effects of Pentobarbital and Isoflurane on Conditioned Learning after Transient Global Cerebral Ischemia in Rabbits

2000 ◽  
Vol 92 (1) ◽  
pp. 171-171 ◽  
Author(s):  
Jae Young Kwon ◽  
Andreas Bacher ◽  
Donald J. Deyo ◽  
John F. Disterhoft ◽  
Tatsuo Uchida ◽  
...  
Keyword(s):  
Cerebral Ischemia ◽  
Conditioned Stimulus ◽  
Unconditioned Stimulus ◽  
Conditioned Response ◽  
Global Cerebral Ischemia ◽  
Eyeblink Response ◽  
Trace Interval ◽  
Transient Global Cerebral Ischemia ◽  
Isoflurane Group ◽  
Conditioned Responses

Background The acquisition of a conditioned eyeblink response has been used extensively to study the neurologic substrates of learning and memory. We examined the effects of the anesthetics isoflurane and pentobarbital, or hypothermia (30 degrees C), on the ability of rabbits to acquire an eyeblink conditioned response after 6.5 min of cerebral ischemia. Methods New Zealand white rabbits (n = 48) were randomly assigned to sham, normothermic, hypothermic, isoflurane, or pentobarbital groups. In the normothermic, hypothermic, isoflurane, and pentobarbital groups, 6.5 min of global cerebral ischemia was produced. In animals randomized to the isoflurane and pentobarbital groups, a pattern of burst suppression was achieved on the electroencephalogram before the start of the ischemic episode. Animals in the hypothermia group were cooled to 30 degrees C before ischemia. Seven days after ischemia, eyeblink training was started using an audible tone presented for 100 ms as the conditioned stimulus. The unconditioned stimulus was an air puff directed at the cornea. The delay between the end of conditioned stimulus and the start of the unconditioned stimulus (the trace interval) was 300 ms in duration. A conditioned response was defined as an eyeblink that was initiated during the trace interval. Eighty trials per day and 15 days of training were delivered. Results Neurologic deficits were greatest in the normothermia group, and these animals also had fewer conditioned responses than those in the sham, hypothermia, or pentobarbital groups. Animals in the isoflurane group had an intermediate number of conditioned responses that was not significantly different from the normothermia group. Conclusions This study demonstrates that a brief episode of cerebral ischemia results in the impairment of associative learning. Hypothermia and burst-suppressive doses of pentobarbital were able to improve neurobehavioral outcome as measured by ability to acquire a trace conditioned response.

Definition of Torture in US Law

2017 ◽  
Author(s):  
Metin Başoğlu
Keyword(s):  
Learned Helplessness ◽  
Scientific Evidence ◽  
Scientific Basis ◽  
Committee Report ◽  
The Us ◽  
Interrogation Techniques ◽  
Us Senate ◽  
Definition Of ◽  
Enhanced Interrogation ◽  
Torture Memos

In the light of the US Senate Intelligence Committee Report on the Central Intelligence Agency’s detention and interrogation program confirming the use of “enhanced interrogation techniques” to induce “learned helplessness” in detainees, this chapter reviews the scientific basis for the US definition of torture and its interpretation in the “Torture Memos.” These memoranda clearly indicate that “enhanced interrogation techniques” are designed for use in combination with specific intent to induce learned helplessness. Abundant research evidence shows that learned helplessness is mental harm that is severe enough to qualify as torture even by US standards. Although the US definition of torture seems to create potential loopholes for impunity, it suffers from certain logical inconsistencies, scientifically unfounded assumptions, and perhaps even “loopholes” that may well render legal cover for use of “enhanced interrogation techniques” difficult, if not impossible—at least not possible in a way that can be justified by logical reasoning or scientific evidence.

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