PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “IMPRINTING (PSYCHOLOGY)”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 199 records · Page 11Linked to original sources

Development of dopamine receptors in the forebrain of the domestic chick in relation to auditory imprinting. An autoradiographic study.

The rostro-medial neostriatum/hyperstriatum ventrale (MNH) and the neostriatum dorsocaudale (Ndc) are forebrain regions which play a role in auditory filial imprinting. Both regions receive a distinct dopaminergic input from the mesencephalon and we were interested to investigate if the dopaminergic system, which is known to play a role in associative learning processes and neuronal plasticity is involved in auditory imprinting. Using ligand autoradiography we studied the distribution and density of dopamine receptors (D1 and D2 type) in the forebrain of socially isolated chicks during the first postnatal week and compared these data with the values of age-matched imprinted chicks. D1- and D2-receptors were present in the chick forebrain on the day of hatching and they showed in general, the same distribution until postnatal day 7. Between days 0 and 2 the D2-receptor density increased significantly in the lobus parolfactorius and paleostriatum augmentatum while for D1-receptor density no significant changes were detectable. The receptor densities in the investigated forebrain regions did not differ significantly between imprinted and control chicks. These results suggest that auditory imprinting does not induce alterations of dopamine receptor density, however, more subtle changes can not be excluded. The presented detailed data about the developmental profile of dopamine receptors within distinct brain regions is a further step towards a more specific interpretation of behavioral effects of dopamine receptor agonists or antagonists at different postnatal ages.

Acoustic Stimulation↗

Dissociation of recognition memory and associative learning by a restricted lesion of the chick forebrain.

Bilateral lesions of a restricted part of the chick forebrain (IMHV) have been shown to impair the acquisition and retention of imprinting preferences. The present study sought to determine the effects of such lesions on an operant conditioning task in which the reward was the presentation of one of two conspicuous objects, a stuffed jungle fowl or an illuminated red box. Twelve hours after hatching 28 domestic chicks received bilateral lesions of IMHV. Thirty-two chicks served as sham-operated controls. On the following day all birds underwent two sessions of operant training. After the second session the chicks were given a preference test. In this test the reinforcing object (box or fowl) and a novel object (fowl or box, whichever had not been seen before) were simultaneously presented. One test was given 2 hr and a second 24 hr after the termination of the operant task. The lesioned birds were not impaired on the operant task or on measures of general activity. In contrast, these birds failed to show a preference for the reinforcing object whereas the sham-operated controls strongly preferred this object. These results suggest that object recognition and associative learning can be dissociated in young chicks. This dissociation is reminiscent of certain human amnesias. The lesion did not impair an expected increase in preference for the stuffed fowl which developed in all birds between the 2-hr and 24-hr preference tests.

Animals↗

Memory systems in the chick: dissociations and neuronal analysis.

Young domestic chicks learn to recognize the visual characteristics of an object to which they are exposed. A restricted part of the forebrain, the intermediate and medial part of the hyperstriatum ventrale (IMHV) is implicated in this process. This form of exposure learning can be dissociated from (i) the ability to learn certain procedures or skills, and (ii) a predisposition to attend to particular types of naturalistic objects. The first of these dissociations is reminiscent of that found in certain human organic amnesias, whilst the second may have its counterpart in the processes involved in face recognition by infants. The right and left IMHV play different roles in the memory that underlies imprinting. The cellular and molecular processes involved in this form of memory are discussed.

Animals↗

Olfactory lateralization in the chick.

Chicks using their right nostril (and so with direct olfactory input to the right hemisphere), and presented simultaneously with two objects identical in visual appearance with the rearing object, and differing only in odour, chose that which smelled like the rearing object. Chicks using the left nostril chose equally readily but at random. Earlier work, using similar tests, has shown special interest of the right hemisphere in change in visual properties of familiar stimuli, suggesting that analysis of a wide range of properties of a familiar stimulus may be an important function of the right hemisphere in the chick, with consequent detection of novelty.

Animals↗

Effects of rhythmic hyperstriatal stimulation on chicks' preferences for visual flicker.

Chicks' preferences for the frequency of a flashing light can be modified by electrically stimulating the medial part of the hyperstriatum ventrale with trains of shocks at that frequency. Chicks stimulated with 1.5 pulse trains s-1 preferred a light flashing at 1.5 s-1 and chicks stimulated at 4.5 trains s-1 preferred a light flashing at 4.5 s-1. Three behavioural measures taken during the preference test, namely measures of movement, latency to approach and distress calls were not significantly influenced by the frequency of brain stimulation.

Animals↗

Paradoxical sleep augmentation after imprinting in the domestic chick.

The EEG and EMG of two groups of chicks (Gallus domesticus), (an experimental one who was imprinted, and a control one who was not), were recorded during 3 hours before and 3 hours after imprinting. The fertilized eggs were kept in an incubator under controlled temperature and humidity until ecclosion occurred. The recording session began 10 hours after ecclosion and after two hours of habituation to the recording conditions. During the imprinting session, E group met a natural stuffed white hen moved by a slow motor. The total amount of time spent in paradoxical sleep (PS), as well as the number of PS episodes increased significantly following imprinting in the E group. Opposite results were found in C group: total amount and number of PS episodes decreased significantly after the pseudo-imprinting session. Neither slow wave sleep, nor wakefulness were modified.

Animals↗

The importance of olfactory bulb noradrenalin for maternal recognition in sheep.

Herds of grazing mammals characteristically produce precocial offspring in synchrony, and it is therefore important for the mother to form a rapid recognition of her own offspring to distinguish them from others. In sheep, the ewe forms such a selective bond with her lamb within 2-4 hours of parturition, a bond which is primarily dependent on olfactory sensory recognition. Here we report that the neuronal mechanism whereby the olfactory "imprint" is made is dependent on the centrifugal noradrenergic projections to the olfactory bulbs. Lesioning of this neural pathway prevents the ewe from forming a selective bond with her own lamb, enabling her to adopt alien lambs.

Animals↗

The gonadotropic-axis involvement in the course of the filial following response in the domestic fowl chick.

The detachment process of the domestic chick from its mother, or any other imprinting object occurs between the sixth and tenth week after hatching. The present study (Experiment I), examines whether the detachment process parallels endocrine events that precede prepuberty. Immediately upon hatching, groups of heavy strain chicks were imprinted to a colored foam rubber ball for 72 hours. The bond between these chicks and the imprinting object was then tested, and plasma LH and testosterone were assayed once a week until the chicks were 10 weeks of age; the sexual development of chicks of the same strain was studied at the same time. At the outset of the detachment period (5-7 weeks) an increase in plasma testosterone and a decrease in plasma LH was found. In addition, the comb and testes showed a definite weight increase while the bursa of Fabricius showed a significant decline in weight. In Experiment II, the beginning of the detachment process was induced by injecting 3 to 4 week old chicks with testosterone-propionate, estradiol-benzoate and 5 alpha-dihydrotestosterone. Our evidence therefore appears to demonstrate that testosterone and its metabolites induce the detachment process by the same mechanism used to stimulate sexual behavior in juvenile chicks.

Animals↗

Persistence of approach response after decerebration in newly hatched quail chicks.

The role of telencephalon in controlling the unconditional approach response was studied in newly hatched Japanese quail chicks by lesions. Approach to flickering light and a moving object were not diminished by ablation of various telencephalic areas, ranging from caudal forebrain lesions to complete bilateral hemispherectomy. Open field activity and tonic immobility were likewise unaffected. Results indicated that the neural mediation of unconditional sensory-motor components of imprinting is anatomically separated from the telencephalon, where recognition memory is thought to be formed.

Animals↗

Effects of diencephalic lesions on approach responses and color preferences in quail.

The effects of stereotaxic radio-frequency lesions on artificially selected approach responses and artificially selected or imprinted red or blue preferences were studied in Japanese quail chicks. No effects were found from lesions in anterior preoptic or pretectal areas and only slight attenuation of red preferences by lesions in nucleus rotundus, opticus principalis thalami and geniculatus lateralis pars ventralis. Extensive lesions in medial diencephalic and bordering areas of telencephalon, ansa lenticularis, lateral and medial forebrain bundle diminished approach tendencies and greatly attenuated the genetically influenced red preferences. Medial diencephalic lesions confined to the dorsomedial thalamic complex and lateral hypothalamus left approach tendencies intact but similarly attenuated only red preferences. Imprinted red or blue preferences of a highly imprintable quail line were also attenuated; red preference strongly, blue preference moderately. The data indicate differential diencephalic mediation of the quail's genetically distinct color preferences and suggest diverse subtelencephalic channels for mediation of approach responses and stimulus preferences. The results also suggest common neural mediation of genetically determined and acquired stimulus preferences.

Animals↗