Covariation of alternative measures of responding in rabbit (Oryctolagus cuniculus) eyeblink conditioning during acquisition training and tone generalization.

Abstract

The likelihood, size, and speed of eyelid movements are thought to covary during the acquisition and expression of conditioning in rabbits (Oryctolagus cuniculus) and are generally accepted as interchangeable measures of the associative strength activated by the conditioned stimulus (CS). To test this assumption, the authors examined the patterns of covariation in these eyelid movement measures in acquisition and stimulus generalization in the upper eyelid and nictitating membrane. Rather than the expected covariation among these measures, eyelid movement magnitudes during the CS were distributed in approximately a bimodal manner. That is, eyelid activity consisted largely of a mixture of very small (< 0.125 mm) baseline measurements and larger (> 1 mm) movements. The results are discussed with respect to their implications for real-time models of eyelid conditioning.

Stimulus specificity of concurrent recovery in the rabbit nictitating membrane response

“…External findings suggest that there may have been sufficient intramodal generalization to explain most of the responding to T2 in Stage 3. Generalization between 500 Hz versus 5000 Hz has never been directly assessed in the rabbit NM preparation, but there has been a recent examination of auditory generalization in the rabbit in which a 1000-Hz tone was used as the CS, and testing was conducted using tone frequencies ranging up to 5040 Hz (Garcia et al, 2003). Responding to the 1000-Hz CS reached 91% CRs, and responding to the 5040-Hz test stimulus was 34% CRs.…”

“…In addition, there was a moderate overlap in encoding between the two tones, such that when Tone 1 was presented T2 was activated at a 0.2 level; likewise, when Tone 2 was presented, T1 was activated at a 0.2 level. This activation level was based on generalization between comparable tone frequencies seen by Garcia et al (2003). The activation of the sensory units was bounded from 0 to 1.…”

“…frequencies (e.g., Garcia, Mauk, Weidemann, & Kehoe, 2003;Moore, 1972). In contrast, there is no evidence that NM responding shows generalization across modalities, even at a subthreshold level.…”

Cholesterol enhances classical conditioning of the rabbit heart rate response

“…In order to overcome the statistical limitations of empty data cells produced by subthreshold US intensities without introducing the potential biases of data imputation, we used dependent variable measures of magnitude of the NMR and magnitude of the NMR area. These measures included all amplitudes and areas above the baseline regardless of whether or not a NMR met the 0.5-mm criterion (Gracia, Mauk, Weidemann, & Kehoe, 2003). NMR topographies for each of the US intensities were averaged across subjects and US durations and examined for differences by comparing the shape of the averaged response Seager, Smith-Bell, & Schreurs, 2003).…”

Neuroscience and Learning: Lessons From Studying the Involvement of a Region of Cerebellar Cortex in Eyeblink Classical Conditioning

“…They reported correlations between measurement techniques as high as 0.99 when response magnitude and onset latency were considered. In another study, however, Garcia, Mauk, Weidemann, and Kehoe (2003) compared upper eyelid responses recorded with an infrared LED system with nictitating membrane responses recorded with a photoelectric transducer. They showed that while magnitude and likelihood measurements were interchangeable, response amplitude, onset latency, and peak latency measures were not.…”