STIMULUS GENERALIZATION AS A FUNCTION OF THE DELAY BETWEEN TRAINING AND TESTING PROCEDURES: A REEVALUATION<sup>1</sup>

Thomas, David R.; Burr, D. E. Scott

doi:10.1901/jeab.1969.12-105

Cited by 38 publications

(51 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As already mentioned, increased generalization with increasing length of the training-test interval has been repeatedly found in different learning tasks (see, e.g., Gisquet-Verrier & Alexinsky, 1986;Perkins & Weyant, 1958;Thomas & Burr, 1969;Thomas & Lopez, 1962). Like the prior findings, the present findings of an equivalent latent inhibition effect following preexposure to the elements or to the compound with a 21-day retention interval appears to reflect forgetting of the detailed characteristics or attributes of preexposed stimuli over time.…”

Section: Discussionsupporting

confidence: 88%

Effects of elements or compound preexposure on conditioned taste aversion as a function of retention interval

Álvarez

López

1995

Animal Learning & Behavior

View full text Add to dashboard Cite

The effects of element or compound preexposure and retention interval were examined in three experiments with the taste-aversion paradigm. In Experiment 1, preexposure to the elements of a compound flavor produced less latent inhibition to the compound than did preexposure to the compound itself when a I-day preexposure--conditioning interval was used. However, preexposing the elements or the compound resulted in equivalent latent inhibition effects when a 2I-day retention interval was used. In Experiment 2, a similar pattern of results was observed when the conditioning-test interval was manipulated. Experiment 3 explored the effect of element or compound preexposure when preexposure and test were carried out in different contexts. Attenuated latent inhibition following preexposure to the elements was found when preexposure and test were carried out in the same context. In contrast, preexposure to the elements resulted in as much latent inhibition as did preexposure to the compound when the context was switched from preexposure to testing. The implications of these findings for a retrieval-oriented view of latent inhibition are discussed.

show abstract

Section: Discussionsupporting

confidence: 88%

Effects of elements or compound preexposure on conditioned taste aversion as a function of retention interval

Álvarez

López

1995

Animal Learning & Behavior

View full text Add to dashboard Cite

show abstract

“…delay between training and test. Thomas and colleagues (1960; 1969; 1982; 1985) reported that pigeons showed the peak shift effect after this and longer delays. Comparable tests have not been performed in humans.…”

Section: Methodsmentioning

confidence: 93%

“…The effect occurs for stimuli varying in brightness (Newlin et al, 1979; Thomas, Ost, & Thomas, 1960; White & Thomas, 1979; Thomas, Mood, Morrison. & Wiertelak, 1991), facial characteristics (Lewis & Johnston, 1999; McLaren & Mackintosh, 2002; Spetch et al, 2004), spatial location (Cheng & Spetch, 2002), pitch (Galizio, 1985; Galizio & Baron, 1979), line tilt (Winton and Beale, 1971; Spetch et al, 2004), floor tilt (Riccio, Urda, & Thomas, 1966; Thomas & Burr, 1969; Thomas & Lyons, 1968), numerosity (Honig & Stewart, 1993), and motor movement (Dickinson & Hedges, 1986). As with other generalization phenomena, the processes postulated to give rise to the peak shift effect have been different for humans and nonhumans, despite its apparent universality.…”

mentioning

confidence: 99%

Learning-related shifts in generalization gradients for complex sounds

Wisniewski

Church

Mercado

2009

Learning & Behavior

View full text Add to dashboard Cite

Learning to discriminate stimuli can alter how one distinguishes related stimuli. For instance, training an individual to differentiate between two stimuli along a single dimension can alter how that individual generalizes learned responses. In this study, we examined the persistence of shifts in generalization gradients after training with sounds. University students were trained to differentiate two sounds that varied along a complex acoustic dimension. The students were subsequently tested on their ability to recognize a sound that they had experienced during training when it was presented among several novel sounds varying along this same dimension. Peak shift was observed in Experiment 1, in which generalization tests immediately followed training, and in Experiment 2, in which the tests were delayed by 24 h. These findings further support the universality of generalization processes across species, modalities, and levels of stimulus complexity. They also raise new questions about the mechanisms underlying learning-related shifts in generalization gradients. The sound stimuli from this study are available as .wav files from http://lb.psychonomic-journals.org/content/supplemental.

show abstract

“…In the laboratory, time-dependent effects can be revealed by simply varying the duration between learning and test. Research in animal associative learning shows that as time from initial conditioning elapses, animals respond to a broader range of cues (e.g., different tones or colors) that decreasingly resemble the originally reinforced cue (21)(22)(23)(24). Notably, much of the stimulus generalization research on delayed testing has involved instrumental appetitive conditioning; how delayed testing affects generalization of Pavlovian threat learning, per se, has been explored almost exclusively in the realm of context conditioning (1,6), in which the animal learns to associate the environment itself-rather than a single cue-with an aversive unconditioned stimulus (US).…”

mentioning

confidence: 99%

Stress promotes generalization of older but not recent threat memories

Dunsmoor

Otto

Phelps

2017

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Stress broadly affects the ability to regulate emotions and may contribute to generalization of threat-related behaviors to harmless stimuli. Behavioral generalization also tends to increase over time as memory precision for recent events gives way to more gist-like representations. Thus, acute stress coupled with a delay in time from a negative experience may be a strong predictor of the transition from normal to generalized fear expression. Here, we investigated the effect of a single-episode acute stressor on generalization of aversive learning when stress is administered either immediately after an aversive learning event or following a delay. In a betweensubjects design, healthy adult volunteers underwent threat (fear) conditioning using a tone-conditioned stimulus paired with an electric shock to the wrist and another tone not paired with shock. Behavioral generalization was tested to a range of novel tones either on the same day (experiment 1) or 24 h later (experiment 2) and was preceded by either an acute stress induction or a control task. Anticipatory sympathetic arousal [i.e., skin conductance responses (SCRs)] and explicit measures of shock expectancy served as dependent measures. Stress administered shortly after threat conditioning did not affect behavioral generalization. In contrast, stress administered following a delay led to heightened arousal and increased generalization of SCRs and explicit measures of shock expectancy. These findings show that acute stress increases generalization of older but not recent threat memories and have clinical relevance to understanding overgeneralization characteristics of anxiety and stress-related disorders.stress | Pavlovian conditioning | associative learning | generalization | memory A number of anxiety and stress-related disorders can be characterized by an inability to discriminate threat from safety. For instance, a core symptom of trauma-and stressrelated disorders [e.g., posttraumatic stress disorder (PTSD)] is persistent and widespread fear and avoidance of myriad harmless cues that act as reminders of the trauma, often referred to as overgeneralization (1). A key component of overgeneralization in anxiety and stress-related disorders may hinge on stress-induced changes in neural circuitry underlying the ability to discriminate threat from safety and regulate emotional responses (2-4). Behavioral generalization also tends to increase over time, as memory precision for recent events gives way to more gist-like representations (5, 6). It then follows that stress-induced impairments in discriminating threat from safety coupled with a loss of memory precision might jointly influence the transition away from normal fear (i.e., highly specific to a known threat) toward overgeneralized fear. Here, we investigate how acute stress and the time between learning and test impacts fear generalization in humans.The effects of stress on the ability to regulate defensive behaviors have been detailed using Pavlovian threat (fear) conditioning tasks in humans and labo...

show abstract

STIMULUS GENERALIZATION AS A FUNCTION OF THE DELAY BETWEEN TRAINING AND TESTING PROCEDURES: A REEVALUATION¹

Cited by 38 publications

References 8 publications

Effects of elements or compound preexposure on conditioned taste aversion as a function of retention interval

Effects of elements or compound preexposure on conditioned taste aversion as a function of retention interval

Learning-related shifts in generalization gradients for complex sounds

Stress promotes generalization of older but not recent threat memories

Contact Info

Product

Resources

About

STIMULUS GENERALIZATION AS A FUNCTION OF THE DELAY BETWEEN TRAINING AND TESTING PROCEDURES: A REEVALUATION1

Cited by 38 publications

References 8 publications

Effects of elements or compound preexposure on conditioned taste aversion as a function of retention interval

Effects of elements or compound preexposure on conditioned taste aversion as a function of retention interval

Learning-related shifts in generalization gradients for complex sounds

Stress promotes generalization of older but not recent threat memories

Contact Info

Product

Resources

About

STIMULUS GENERALIZATION AS A FUNCTION OF THE DELAY BETWEEN TRAINING AND TESTING PROCEDURES: A REEVALUATION¹