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K Zieliński

Publications and source records attributed to K Zieliński.

At least 19 recordsLinked to original sources
PubMed1991

Intertrial responses of rats in two-way avoidance learning to visual and auditory stimuli.

Learning and performance of two-way avoidance were investigated in a total of 68 rats trained with either a visual (change in illumination to darkness or to light) or an auditory (white noise of 70 or 60 dB intensity) conditioned stimulus (CS). Experiment I showed that the darkness CS produce lower avoidance performance and a much higher rate of intertrial responses than either a auditory or a compound (visual plus auditory) CS. A monotonic within-session increase of avoidance performance and a similar, but less regular increase of intertrial responses were found at the beginning of training in each group. In later sessions such trends were observed only in rats trained with a visual CS. Experiments II and III showed also rapid transfer of avoidance response and a corresponding change of intertrial response rate with the change of CS modality. When the compound CS was used, the effects of the visual element were completely overcome by the auditory one. Rats trained with a visual CS in Experiment IV showed a positive correlation between avoidance performance and the number of intertrial responses, which was more pronounced in earlier than in later training sessions. We consider the rise of intertrial behaviour as an adaptive response to the increase of task difficulty. CSi of different modalities differ not only in relative saliency, but also in the discriminability between their onset and offset. The modality of the CS influences not only avoidance performance but also the course of learning.

Acoustic Stimulation↗
PubMed1991

Contribution of vascular network transformation of the heart to the pathogenesis of ischaemic heart disease. Qualitative changes in myocardial angioarchitectonics.

Based on the idea of segmental arterial vascularization of the heart as well as qualitative assessment of angio- and microangiograms, transformations of intramyocardial vascularization induced by atherosclerotic lesions of the extramyocardial coronary arteries have been presented. Using various angiographic methods, vascularization was evaluated in 58 cases of acute and chronic ischaemic heart disease. Attention was paid to transformations of spatial structure of the vascular network and it was found that some morphological forms of ischaemic heart disease are characterized by a progressive remodelling of the peripheral vascular bed microangioarchitectonics which seems to be of major importance for exacerbation pathomechanisms. Two group of angiographic changes in the ischaemic myocardium have been distinguished, which consisted in disturbances of the segmental pattern of myocardial vascularization and disturbances of the intrasegmental structure of the arterial bundles and capillary vessels.

Adult↗
PubMed1979

Involvement of the partial reinforcement procedure in reward training: open address.

The analysis of the course of reward training presented in early Konorski and Miller’s papers (1933, 1936) indicates that the appearance of active instrumental responses is related with the introduction of the partially reinforced, excitatory classically conditioned procedure. It is postulated that the mechanism underlying the effects of this procedure on the shaping of instrumental responses is similar to that proposed by Konorski (1967) for the effects of inhibitory classically conditioned stimuli on the performance of the instrumental response.

Animals↗
PubMed1979

Avoidance acquisition in cats as a function of temporal and intensity factors.

Acquisition of an active bar-pressing avoidance response was investigated in a factorial design with 3, 5 or 9 s CS-US intervals and CSs of 70- or 50-dB of white noise. As the CS-US interval increased the required time to meet the avoidance criterion decreased. The shorter the CS-US interval and the more intense the CS, the shorter the median response latencies observed at the end of the training. The latency data were analyzed in Vincentized fifths of acquisition trials. At the beginning of training, when the highest proportion of responses occurred soon after the US onset, escape latencies were shorter in groups trained with shorter CS-US intervals and the more intense CS. During the 1st and 2nd fifths of training, avoidances occurred with the same probability in each part the CS-US interval. By the middle of the training, after a performance level of 50 percent avoidance responses was reached, a rapid increase in the number of short-latency avoidance was observed, which was more pronounced in groups trained with the 70 dB CS. While the general shape of the latency distributions was preserved during the remaining two fifths of the training, a further increase in the intensity effect was noted, which occurred along with a decrease in the CS-US interval effect. The data are in favour of Two-factor Theory of Avoidance learning and suggest that at various stages of training, different variables emerge for acquisition and consolidation of the avoidance reflex. Data supported the hypothesis that two different mechanisms are involved in performance of short- and long-latency avoidance responses.

Animals↗
PubMed1979

Cueing properties of the decrease of white noise intensity for avoidance conditioning in cats.

In the main experiment two groups of 6 cats each were trained in active bar-pressing avoidance to a CS consisting of either a 10 dB or 20 dB decrease of the background white noise of 70 dB intensity. The two groups did not differ in rapidity of learning, however cats trained to the greater change .in background noise performed avoidance responses with shorter latencies than did cats trained to smaller change. Within-groups comparisons of cumulative distributions of response latencies for consecutive Vincentized fifths of avoidance acquisition showed the greatest changes in the region of latencies longer than the median latency of instrumental responses. On the other hand, the effects of CS intensity found in between-groups comparisons were located in the region of latencies shorter than the median latency of either group. Comparisons with data obtained in a complementary experiment employing additional 17 cats showed that subjects trained to stimuli less intense than the background noise level were marked by an exceptionally low level of avoidance responding with latencies shorter than 1.1 s, which was lower than expected from the probability of intertrial responses for this period of time. Due to this property of stimuli less intense than the background, the distributions of response latencies were moved to the right, in effect, prefrontal lesions influenced a greater part of latency distributions than in cats trained to stimuli more intense than the background.

Animals↗
PubMed1979

Auditory frequency generalization in normal and prefrontal dogs trained in varieties of active avoidance reflexes.

Twelve dogs were trained to avoid shock with response contingent termination of a 1000 Hz tonal CS on all trials, whereas 12 additional dogs received the same training except that on 50 percent trials there was a fixed CS duration and no shock. Initial acquisition revealed that CS prolongation resulted in longer response latencies compared to subjects trained with response contingent CS termination. Both training groups were then assigned to subgroups (n=4) that received either lateral or medial lesions of the prefrontal cortex or a rest pause of 10 days. Postsurgical reacquisition indicated a medial deficit in response latencies for both training groups whereas performance levels of normal and lateral groups were comparable. Two generalization tests to tones of 600-, 800-, 1000-, 1200-, and 1400-Hz followed. During the sampled test only one block of the five test frequencies occurred with the regular 15 training trials, while the tonal frequencies were presented on all 20 daily extinction trials during massed generalization testing. No evidence of extinction was observed during the sampled generalization test in either training group. However, during massed testing, all subjects trained with response contingent CS termination showed an overall extinction influence, which was most pronounced in the medial subgroup, although the laterals showed frequency control as well. In the group trained with CS prolongation the controls had clear, discriminative performance, while little stimulus control or extinction influence were found in the medial or lateral subgroups. Comparison with alimentary data indicated much broader tonal frequency generalization in dogs trained in avoidance. However, when the procedures reduced avoidance levels, double dissociation of medial and lateral lesion effects on stimulus control and susceptibility to extinction emerged.

Acoustic Stimulation↗
PubMed1978

Stimulus intensity effects of acute extinction of the CER in rats.

Two groups of 9 rats were trained in the conditioned emotional response (CER) consisting of suppression of food-motivated behavior as a consequence of the pairing of white noise with unavoidable shock. One group was trained and then extinguished with an 80 dB white noise value and the other with the 50 dB white noise intensity as the conditioned stimulus (CS). The CER acquisition was faster with the more intense CS, however, on the last training day, conditioned suppression reached the same asymptotic level in both groups. Then an acute extinction procedure was introduced, wherein the CS was presented only once a day and lasted continuously until the end of the session with no US presentation during this period. This procedure was repeated over several consecutive days. During the first prolonged CS action, CER extinction was more rapid in the 50- than in 80-dB group. However, on the next extinction day the amount of suppression was less with the more intense CS. The results were discussed in terms of CS intensity effects on learning and performance of the conditioned response.

Acoustic Stimulation↗
PubMed1978

Effects of lesions in the amygdaloid nucleus centralis on acquisition and retention of avoidance reflexes in cats.

Acquisition and retention of bar-press avoidance responses after lesions of the lateral part of the amygdaloid nucleus centralis were investigated in 17 adult male cats. The lesions were administered either 10 days (5 cats), or 35 days (7 cats) before training. The remaining 5 cats served initially as intact controls and then, after extensive training, were given similar lesions to test for the effects on retention of the task. The lesions resulted in both retarded avoidance acquisition and a decreased proportion of short latency responses. A short post-operative pause resulted in stronger lesion effects on the length of training and deterioration in short-latency response performance, but a smaller effect on the increase in intertrial responding than was found after a long post-operative pause. The lesioned cats showed more oscillations between runs of escape and avoidance responses than normal, control cats. The immediate effect of lesions on well-trained avoidance reflexes consisted of a decrease in avoidance performance and marked prolongation of escape latencies. The deterioration in short-latency avoidance responding was irreversible in spite of extensive post-operative retraining.

Amygdala↗
PubMed1977

Stimulus intensity and conditioned suppression magnitude: dependence upon the type of comparison and stage of training.

Three groups of eight rats each were trained in conditioned emotional response (CER) using white noise of 70 dB, 50 dB, or both intensities as conditioned stimuli (CSi) given in unpredictable order. Between-subjects comparisons showed more rapid acquisition to the 70- than to the 50-dB CS. Rats presented with both intensities acquired the CER at a similar rate as those conditioned to the 70 dB value only, and within-subjects comparison did not reveal any CS intensity effects. During the next stage of the experiment all rats were presented with both intensities of white noise. The stimulus intensity effect found in within-subjects comparisons was greatest when the soft CS replaced the more intense value on half of trials. Weakening of the CER after reaching asymptotic conditioning was related to increased response rate at the beginning of CS action with greater suppression of bar presses before shock onset. This decreasing pattern of bar presses within CS action was far more consistent on 70-dB trials, indicating a stimulus intensity effect on the development of the inhibition of delay in CER training.

Acoustic Stimulation↗
PubMed1977

Tooth pulp stimulation as an unconditioned stimulus in defensive instrumental conditioning.

In an experiment performed on five cats, stable escape and avoidance reflexes in a bar-pressing situation were established using tooth pulp electric stimulation as the unconditioned stimulus. The influence of changes in parameters of the unconditioned stimulus (current intensity, single pulse and train durations, frequency of pulses and rate of train presentations) on unconditioned and instrumental responses was analysed in three additional subjects. Among other relationships the dependence of the threshold of bar press responses on the amount of charge in a single pulse was determined.

Animals↗
PubMed1977

Auditory intensity generalization after CER differentiation training.

Auditory intensity generalization was tested in 32 rats trained in CER (conditioned emotional response) differentiation between the 50- and 70-dB white noise intensities. All generalization gradients showed regular monotonicity across the noise intensity dimension independently on experience with the CS+ value prior to the differentiation training. Two kinds of peak shift were obtained. Stimuli further away from the CS? value and more intense than the CS+ inhibited the on-going food motivated behavior more strongly than the CS+ itself. Stimuli further away from the CS+ value and more intense than the CS? enhanced the on-going behavior more than the CS?. A method of statistical analysis indicated that individual gradients and group data corresponded to the same generalization functions.

Acoustic Stimulation↗
PubMed1976

Auditory frequency generalization with differing extinction influences in normal and prefrontal dogs trained in instrumental alimentary reflexes.

Following criterion of 90 percent correct responses to a 1,000-Hz tone on a 50 percent reinforcement schedule, 8 of 12 dogs were subjected to lesions of the medial or lateral prefrontal cortex. Three types of auditory frequency generalization tests followed separated by a period of reacquisition of the instrumental response. A sampling procedure of generalization assessment, wherein a block of test trials was contained within 15 partially reinforced trials and repeated over 16 days, revealed complete generalization in the medials and rapid, but discriminative responding in the laterals. The second generalization test was conducted in complete extinction over 5 days. The medials yielded discriminative performance and least overall resistance to extinction, while the laterals showed a higher amount of frequency control and minimal extinction effects. Go-no go differentiation training preceeded the last generalization test [CS(+) = 1,000 Hz; CS(-) = 600 Hz], resulting in retarded acquisition in the laterals and easiest acquisition in the medials. The last generalization test suggested that all groups were comparable, with some trend toward more rapid extinction in the medial dogs. Collectively, the data indicated that performance was determined by the interacting functions between the specific lesions and the density of reinforcement present in the testing procedure.

Animals↗