Cogprints: No conditions. Results ordered -Date, Title. 2018-01-17T14:26:05ZEPrintshttp://cogprints.org/images/sitelogo.gifhttp://cogprints.org/2011-12-16T00:08:33Z2011-12-16T00:08:33Zhttp://cogprints.org/id/eprint/7748This item is in the repository with the URL: http://cogprints.org/id/eprint/77482011-12-16T00:08:33ZToward molecular neuroeconomics of obesity.Because obesity is a risk factor for many serious illnesses such as diabetes, better
understandings of obesity and eating disorders have been attracting attention in
neurobiology, psychiatry, and neuroeconomics. This paper presents future study
directions by unifying (i) economic theory of addiction and obesity (Becker and Murphy,
1988; Levy 2002; Dragone 2009), and (ii) recent empirical findings in neuroeconomics
and neurobiology of obesity and addiction. It is suggested that neurobiological
substrates such as adiponectin, dopamine (D2 receptors), endocannabinoids, ghrelin,
leptin, nesfatin-1, norepinephrine, orexin, oxytocin, serotonin, vasopressin, CCK,
GLP-1, MCH, PYY, and stress hormones (e.g., CRF) in the brain (e.g., OFC, VTA,
NAcc, and the hypothalamus) may determine parameters in the economic theory of
obesity. Also, the importance of introducing time-inconsistent and
gain/loss-asymmetrical temporal discounting (intertemporal choice) models based on
Tsallis’ statistics and incorporating time-perception parameters into the neuroeconomic
theory is emphasized. Future directions in the application of the theory to studies in
neuroeconomics and neuropsychiatry of obesity at the molecular level, which may help
medical/psychopharmacological treatments of obesity (e.g., with sibutramine), are
discussed.Taiki Takahashitaikitakahashi@gmail.com2009-02-13T01:14:59Z2011-03-11T08:57:18Zhttp://cogprints.org/id/eprint/6341This item is in the repository with the URL: http://cogprints.org/id/eprint/63412009-02-13T01:14:59ZThe biopsychology of maternal behavior in nonhuman mammals The term “maternal behavior,” when applied to nonhuman mammals, includes the behaviors exhibited in preparation for the arrival of newborn, in the care and protection of the newly arrived young, and in the weaning of those young, and represents a complex predictable pattern that is often regarded as a single, comprehensive, species-specific phenomenon. Although the delivering first-time mammalian mother is immediately and appropriately maternal, a maternal “virgin” with no prior exposure to young does not show immediate and appropriate behavior toward foster young. Nevertheless, the virgin female, and indeed the male, possess the neural circuitry that underlies the pattern referred to as maternal behavior, despite not exhibiting the pattern under normal circumstances. At parturition, or after extensive exposure to young, what emerges appears to be a single stereotyped maternal behavior pattern. However, it is actually a smoothly coordinated constellation of simpler actions with proximate causes that, when sequenced properly, have the appearance of a motivated, purposive, adaptive, pattern of caretaking. Over the past 50 years, much research has focused on finding the principal external and internal factors that convert the nonmaternal behavior patterns of the nonpregnant nullipara, the virgin, to the almost immediate and intense maternal behavior characteristic of the puerpera, the mother. This review is an attempt to summarize the many comprehensive, even encyclopedic, reviews of these factors, with an emphasis on brain mechanisms, and to highlight the gaps that remain in understanding the processes involved in the almost immediate onset of maternal caretaking behaviors observed in mammals at delivery. Where possible, the reader is directed to some of those excellent reviews.Dr. Mark B. Kristalkristal@buffalo.edu2009-03-28T09:32:38Z2011-03-11T08:57:20Zhttp://cogprints.org/id/eprint/6385This item is in the repository with the URL: http://cogprints.org/id/eprint/63852009-03-28T09:32:38ZIngestion of amniotic fluid enhances the facilitative effect of VTA morphine on the onset of maternal behavior in virgin ratsPrevious research has shown that injection of morphine into the ventral tegmental area(VTA) facilitates the onset of maternal behavior in virgin female rats, and injection of the opioid antagonist naltrexone into the VTA disrupts the onset of maternal behavior in parturient rats. Placentophagia – ingestion of placenta and amniotic fluid, usually at parturition – modifies central opioid processes. Ingestion of the active substance in placenta and amniotic fluid, Placental Opioid-Enhancing Factor (POEF), enhances the hypoalgesic effect of centrally administered morphine, and more specifically, enhances δ- and κ-opioid-receptor-
mediated hypoalgesia and attenuates μ-opioid-receptor-mediated hypoalgesia. POEF (in placenta or amniotic fluid) ingestion does not, by itself, produce hypoalgesia. In the
present study, we tested the hypothesis that ingestion of amniotic fluid enhances the facilitative effect of opioid activity (unilateral morphine injection) in the VTA on the rate of onset of maternal behavior. Virgin female Long-Evans rats were given one intra-VTA injection of morphine sulfate (0.0, 0.01, or 0.03 μg, in saline) and an orogastric infusion of 0.25 ml amniotic fluid or saline once each day of the first three days of the 10-day testing
period. Subjects were continuously exposed to foster pups that were replaced every 12 h; replacement of pups was followed by a 15-min observation period. Maternal behavior
latency was determined by the first of two consecutive tests wherein the subject displayed pup retrieval, pup licking in the nest, and crouching over all foster pups, during the 15-min observation. We confirmed the previous finding that the VTA injection, alone, of 0.03 μg morphine shortened the latency to show maternal behavior and that 0.0 μg and 0.01 μg morphine did not. Ingestion of amniotic fluid (and therefore POEF) facilitated the onset of
maternal behavior in rats receiving an intra-VTA microinjection of an otherwise subthreshold dose of morphine (0.01 μg).Anne Neumannaneumann@buffalo.eduRobert F. Hoeyrhoey@buffalo.eduLindsey B. Daiglerldaigler@buffalo.eduDr. Alexis C. Thompsonathompso@ria.buffalo.eduDr. Mark B. Kristalkristal@buffalo.edu2009-07-02T01:41:07Z2011-03-11T08:57:23Zhttp://cogprints.org/id/eprint/6574This item is in the repository with the URL: http://cogprints.org/id/eprint/65742009-07-02T01:41:07ZLighting as a Circadian Rhythm-Entraining and Alertness-Enhancing Stimulus in the Submarine EnvironmentThe human brain can only accommodate a circadian rhythm that closely follows 24 hours. Thus, for a work schedule to meet the brain’s hard-wired requirement, it must employ a 24 hour-based program. However, the 6 hours on, 12 hours off (6/12) submarine watchstanding schedule creates an 18-hour “day” that Submariners must follow. Clearly, the 6/12 schedule categorically fails to meet the brain’s operational design, and no schedule other than one tuned to the brain’s 24 hour rhythm can optimize performance. Providing Submariners with a 24 hour-based watchstanding schedule—combined with effective circadian entrainment techniques using carefully-timed exposure to light—would allow crewmembers to work at the peak of their daily performance cycle and acquire more restorative sleep. In the submarine environment, where access to natural light is absent, electric lighting can play an important role in actively entraining—and closely maintaining—circadian regulation. Another area that is likely to have particular importance in the submarine environment is the potential effect of light to help restore or maintain alertness.L. J. CrepeauJ. D. Bulloughbulloj@rpi.eduM. G. FigueiroS. PorterM. S. Rea2013-05-04T23:22:04Z2013-05-04T23:22:04Zhttp://cogprints.org/id/eprint/8955This item is in the repository with the URL: http://cogprints.org/id/eprint/89552013-05-04T23:22:04ZMale-induced estrus synchronization in the female Siberian hamster (Phodopus sungorus sungorus)Olfactory cues play an integral role in the organization of events that mediate reproductive success. In a variety of species, priming
pheromones, in particular, are important for ensuring reproductive fitness. To date, very little research has focused on how male-emitted
priming pheromones, such as those that regulate the onset of puberty and estrus synchronization in females, affect the reproductive
physiology of the female Siberian hamster (Phodopus sungorus sungorus). This lack of research may be due to the physiology of the
Phodopus genus; vaginal cytology cannot be used as a reliable indicator of estrus or ovulation. Using a jugular cannulation technique to
determine estrous stage by blood analysis of prolactin and luteinizing hormone, we sought to determine if male priming pheromones affect
estrous cyclicity in the female Siberian hamster and, if so, whether the production of these priming pheromones is androgen dependent. Our results showed that females exposed to bedding from mature, intact males showed a significantly higher incidence of proestrus 3 days later than did females exposed to the bedding of mature, gonadectomized males. Therefore, we found that not only do male Siberian hamsters emit chemical signals that induce estrus synchronization, but also that this ability is likely to be androgen dependent.Dr. J.C. DodgeDr. M.B. Kristalkristal@buffalo.eduDr. L.L. Badura2002-04-05Z2011-03-11T08:54:54Zhttp://cogprints.org/id/eprint/2163This item is in the repository with the URL: http://cogprints.org/id/eprint/21632002-04-05ZHomosexual Orientation in Males: Evolutionary and Ethological AspectsEvolutionary theory proposes that adaptive traits are reproduced more successfully than maladaptive traits. Accordingly, natural selection should favour heterosexuality as it facilitates reproduction and the propagation of genes. However, the question becomes, what has maintained homosexuality in a small but consistent percentage of the human population? Research into the evolutionary and hormonal factors associated with a homosexual orientation have yielded provocative but inconsistent results. It also suggests that human sexual orientation, and in particular homosexual orientation, is too complex to be described by one simple model or a single research discipline. The current paper treads a new path and emphasises an integrative approach for the understanding of homosexuality. The authors examine the combined effects of evolutionary factors and neurohormonal processes on the development of a homosexual orientation. It is suggested that research into the topic could benefit from an examination of and change in some of the assumptions upon which much past research has been based.Frank MuscarellaBernhard FinkKarl GrammerMichael Kirk-Smith2002-05-29Z2011-03-11T08:54:55Zhttp://cogprints.org/id/eprint/2228This item is in the repository with the URL: http://cogprints.org/id/eprint/22282002-05-29ZHomosexual Orientation in Males: Evolutionary and Ethological AspectsEvolutionary theory proposes that adaptive traits are reproduced more successfully than maladaptive traits. Accordingly, natural selection should favour heterosexuality as it facilitates reproduction and the propagation of genes. However, the question becomes, what has maintained homosexuality in a small but consistent percentage of the human population? Research into the evolutionary and hormonal factors associated with a homosexual orientation have yielded provocative but inconsistent results. It also suggests that human sexual orientation, and in particular homosexual orientation, is too complex to be described by one simple model or a single research discipline. The current paper treads a new path and emphasises an integrative approach for the understanding of homosexuality. The authors examine the combined effects of evolutionary factors and neurohormonal processes on the development of a homosexual orientation. It is suggested that research into the topic could benefit from an examination of and change in some of the assumptions upon which much past research has been based.Frank MuscarellaBernhard FinkKarl GrammerMichael Kirk-Smith2002-04-05Z2011-03-11T08:54:55Zhttp://cogprints.org/id/eprint/2164This item is in the repository with the URL: http://cogprints.org/id/eprint/21642002-04-05ZHuman Pheromones: Integrating Neuroendocrinology and EthologyThe effect of sensory input on hormones is essential to any explanation of mammalian behavior, including aspects of physical attraction. The chemical signals we send have direct and developmental effects on hormone levels in other people. Since we don't know either if, or how, visual cues might have direct and developmental effects on hormone levels in other people, the biological basis for the development of visually perceived human physical attraction is currently somewhat questionable. In contrast, the biological basis for the development of physical attraction based on chemical signals is well detailed.James V. KohlMichaela AtzmuellerBernhard FinkKarl Grammer2002-01-11Z2011-03-11T08:54:52Zhttp://cogprints.org/id/eprint/2018This item is in the repository with the URL: http://cogprints.org/id/eprint/20182002-01-11ZDehydroepiandrosterone sulphate and corticotropin levels are high in young male patients with conduct disorder: comparisons with growth factors, thyroid and gonadal hormonesIntroduction: The biological concomitants of childhood conduct disorder (CD) have seldom been considered separate from those of hyperkinesis with which CD is often comorbid. CD predicts an increased likelihood of developing a personality disorder and is often associated with an antisocial outcome. Childhood CD may originate in a stressful upbringing in a dysfunctional family environment, and has been reported to be associated with unusual physical or sexual development and thyroid dysfunction.
Methods: We therefore explored circulating levels of hormones from adrenal, gonadal and growth-hormone axes associated with stress, aggression and development in 28 CD patients and 13 age-matched healthy children (10-18 years old).
Results:
1/ The CD group had higher levels of dehydroepiandrosterone sulphate (DHEA-S) and corticotropin (ACTH) and for those under 14 years of age there was more free triiodothyronine (fT3) in the circulation.
2/ There were no differences for gonadal hormones, and neither the levels of steroid hormones nor the ratings of maturity (early/late) were associated with aggression, as has been reported elsewhere. 3/ Smaller physical measures in CD children correlated with DHEA-S and growth factors (e.g. IGF-I): 4/ increased ACTH and fT3 correlated with restless-impulsive ratings, and DHEA-S with 'disruptive behaviour'.
Conclusions: Imbalances in the adrenal and growth axes may indeed have neurotrophic repercussions in growth and development.
Dmitrieva Oades Hauffa Eggers2001-04-08Z2011-03-11T08:54:37Zhttp://cogprints.org/id/eprint/1439This item is in the repository with the URL: http://cogprints.org/id/eprint/14392001-04-08ZTestosterone and grasp-reflex differences in human neonatesAccording to the Geschwind-Behan-Galaburda (GBG) hypothesis, prenatal testosterone (T) causes a slowing in the development of the left brain with a consequent compensatory growth in the right brain, creating a reverse organisation of the cerebral lateralisation. That is, left- and right-handedness might be associated with high and low prenatal T levels, respectively. To test this
hypothesis, the relations of T levels (umbilical cord blood) to grasp-reflex strengths were studied in human neonates. Handedness was assessed by measuring
the grasp-reflex strengths from the right and left hands in 10 trials from each hand alternatively. There were two handedness groups: right-handers (R-L significantly
greater than zero) and left-handers (significantly smaller than zero). Contrary to the GBG model, the mean free T concentration was found to be significantly higher in
right-handers than left-handers for males and females. There was no significant difference in the total T levels between right- and left-handers. Free T concentrations positively correlated with R-L grasp-reflex strengths, i.e. right-handedness increased as T increased, and left-handedness increased as T decreased. Contrary to these positive correlations, T negatively correlated with
the grasp-reflex strengths from the right and left hands. These results partly supported the GBG hypothesis for this spinal-motor-asymmetry model. Total T did not significantly correlate with grasp-reflex strengths. The results suggest that prenatal T may at least play a role in prenatal determination of spinal motor lateralisation, with a possible consequent upward regulation of cerebral
lateralisation.
Uner TanMeliha Tan2000-06-14Z2011-03-11T08:53:42Zhttp://cogprints.org/id/eprint/149This item is in the repository with the URL: http://cogprints.org/id/eprint/1492000-06-14ZTHE MIND AND BRAIN SCHOLAR AS A HITCH-HIKER IN POST-GUTENBERG GALAXY: PUBLISHING AT 2000 AND BEYONDElectronic journal (e-journal) publishing has started to change the ways we think about publish-ing. However, many scholars and scientists in the mind and brain sciences are still ignorant of the new possibilities and on-going debates. This paper will provide a summary of the issues in-volved, give an update of the current discussion, and supply practical information on issues re-lated to e- journal publishing and self-archiving relevant for the mind and brain sciences. Issues such as differences between traditional and e-journal publishing, open archive initiatives, world-wide conventions, quality control, costs involved in e-journal publishing, and copyright questions will be addressed. Practical hints on how to self-archive, how to submit to the e-journal Psycolo-quy, how to create an open research archive, and where to find information relevant to e-publishing will be supplied.Brigitte StemmerMarianne CorreYves Joanette2000-05-13Z2011-03-11T08:53:42Zhttp://cogprints.org/id/eprint/147This item is in the repository with the URL: http://cogprints.org/id/eprint/1472000-05-13ZThe study of the regenesis of mind in the 21st centuryThe enigma of consciousness and the brain-mind relationship will - most likely - be unveiled in the 21st century through the new technologies developed at the end of the 20th century and new technologies yet to come. The new technologies will be used to tackle the problem from evolu-tionary, developmental, normal and pathological brain functioning. A major contribution, how-ever, will surface when investigating a particular perspective of pathological brain functioning - a perspective that has not received any attention in the past: the investigation of the re-emergence of mind out of prolonged coma and coma like states.Paul Walter SchönleBrigitte Stemmer1998-11-14Z2011-03-11T08:53:39Zhttp://cogprints.org/id/eprint/69This item is in the repository with the URL: http://cogprints.org/id/eprint/691998-11-14ZParticipation of Placental Opioid-Enhancing Factor in opioid-modulated events at parturitionParturition in mammals occurs in the context of sensory, neurochemical, and endocrinological factors that are orchestrated and timed so that maternal behavior and the object of the behavior, the neonate, "emerge" almost simultaneously. Among the factors found to be important for the suppression of pain during delivery as well as for the emergence of caretaking behavior toward the young, are changes in endogenous opioid activity in the central nervous system. In most mammalian species, these changes are likely initiated by sensory events arising in the distended reproductive tract and abdominal musculature, and are modified by the parturitional endocrine milieu and substances ingested in amniotic fluid and placenta (e.g., Placental Opioid-Enhancing Factor, or POEF). In addition, ingestion of afterbirth material may decrease the probability that the vaginal/cervical sensory stimulation arising during delivery will trigger pseudopregnancy, a condition that decreases, if not eliminates, the likelihood of fertilization in the postpartum estrus. The research described herein primarily focuses on elucidating the manner in which POEF modulates opioid antinociception, and otherwise participates in opioid-mediated parturitional events.M. B. Kristal2009-01-05T23:58:11Z2011-03-11T08:57:17Zhttp://cogprints.org/id/eprint/6311This item is in the repository with the URL: http://cogprints.org/id/eprint/63112009-01-05T23:58:11ZOpioid stimulation in the ventral tegmental area facilitates the onset of maternal behavior in ratsThis research investigated the effect of an increase or decrease in opioid activity in the ventral tegmental area (VTA) on the onset of maternal behavior in rats. In Experiment 1, the latency to show maternal behavior toward foster rat pups (sensitization latency) was determined in maternally naive female rats given either nothing or a unilateral intra-VTA injection of morphine sulfate (MS) (0.0, 0.01, 0.03, 0.1 or 0.3 µg), on the first three days of a 10-day period of constant exposure to pups. Rats treated with 0.03 µg MS had significantly shorter sensitization latencies than did rats treated with 0.0 µg MS, 0.01 µg MS, or receiving no treatment (higher doses of morphine produced intermediate results). The facilitating effect of intra-VTA MS on the onset of maternal behavior was blocked by pretreatment with naltrexone hydrochloride and was found to have a specific site of action in the VTA (MS injections dorsal to the VTA were ineffective). In Experiment 2, sensitization latencies were determined in periparturitional rats given a bilateral intra-VTA injection of either the opioid antagonist naltrexone methobromide (quaternary naltrexone), its vehicle, a sham injection, or left untreated 40 min after delivery of the last pup. The mothers' own pups were removed at delivery; mothers were nonmaternal at the time of testing. Quaternary naltrexone treatment produced significantly slower sensitization to foster pups than did control conditions. Total activity and pup-directed activity did not differ significantly with treatment. The results demonstrate that increased opioid activity in the VTA facilitates the onset of maternal behavior in inexperienced nonpregnant female rats, and decreased opioid activity in the VTA disrupts the rapid onset of maternal behavior at parturition.Alexis C. ThompsonMark B. Kristal1998-11-14Z2011-03-11T08:53:39Zhttp://cogprints.org/id/eprint/68This item is in the repository with the URL: http://cogprints.org/id/eprint/681998-11-14ZIngestion of amniotic fluid by postpartum rats enhances morphine antinociception without liability to maternal behaviorIngestion of amniotic fluid or placenta by rats has been shown to enhance opioid-mediated analgesia induced by morphine injection, foot shock, vaginal/cervical stimulation, or late pregnancy. The present study was designed to determine whether this mechanism might be a means of providing greater analgesia during the periparturitional period without contributing to the disruption of maternal behavior (measured primarily as retrieval) that can result from excessive opioid levels. Postpartum primiparous rats, injected with either 2 or 3 mg/kg morphine sulfate or vehicle and given orogastric infusions of either amniotic fluid or saline, were tested for maternal behavior. Pain threshold (determined by tail-flick latency test) in rats injected with 2 mg/kg morphine and infused with amniotic fluid was elevated to a level that did not differ significantly from that of a separate group of rats injected with 3 mg/kg morphine and infused with saline. This enhanced analgesia was not, however, accompanied by the significant disruption of maternal behavior found among the rats receiving the higher morphine dose.J. A. TarapackiM. PiechM. B. Kristal2001-01-15Z2011-03-11T08:54:29Zhttp://cogprints.org/id/eprint/1229This item is in the repository with the URL: http://cogprints.org/id/eprint/12292001-01-15ZSerum gonadal steroid hormones in young schizophrenic patientsPsychosis is reported to show a later age of onset in women than in men and its nature and course in women may also differ.
Our aim was to see if levels of four steroid hormones at the start of early-onset psychosis differ from other groups of young people and if predicted low levels of estrogen (E2) are a feature of female psychosis. [We would predict that female schizophrenia patients on a child and adoelscent psychiatry ward would show low levels of E2 with its putative neuroleptic like protective properties.]
Methods: Two blood samples from 22 young psychotic patients were analysed by radioimmunoassay for E2, progesterone (PROG), testosterone (TE) and dehydroepiandrosterone sulphate (DHEAS).
Results: Female psychotic patients showed E2 levels lower than matched healthy cycling controls but higher than those on a contraceptive pill: they also showed higher TE levels than controls.
Male psychotic patients had higher DHEAS levels than healthy or obsessive compulsive disorder subjects.
Conclusions: We suggest that illness-related changes of steroids can be measured superimposed on medication - induced changes and that lower E2 levels in psychotic women may increase their vulnerability to psychosis. Changes of TE in female and DHEAS in male psychotics may be more a consequence of the illness. However we postulate that increased DHEAS levels could interfere with normal neurodevelopmental neuronal pruning processes (cf. increased DHEAS levels in male adolescents with conduct disorder, Dmitrieva et al., 1999, 2001)
Oades Schepker1998-02-12Z2011-03-11T08:54:06Zhttp://cogprints.org/id/eprint/595This item is in the repository with the URL: http://cogprints.org/id/eprint/5951998-02-12ZConsciousness, Causality and ComplementarityAbstract of 1991 target article: Investigations of the function of consciousness in human information processing have focused mainly on two questions: (1) where does consciousness enter into the information processing sequence and (2) how does conscious processing differ from preconscious and unconscious processing. Input analysis is thought to be initially "preconscious," "pre-attentive," fast, involuntary, and automatic. This is followed by "conscious," "focal-attentive" analysis which is relatively slow, voluntary, and flexible. It is thought that simple, familiar stimuli can be identified preconsciously, but conscious processing is needed to identify complex, novel stimuli. Conscious processing has also been thought to be necessary for choice, learning and memory, and the organization of complex, novel responses, particularly those requiring planning, reflection, or creativity. The present target article reviews evidence that consciousness performs none of these functions. Consciousness nearly always results from focal-attentive processing (as a form of output) but does not itself enter into this or any other form of human information processing. This suggests that the term "conscious process" needs re-examination. Consciousness appears to be necessary in a variety of tasks because they require focal-attentive processing; if consciousness is absent, focal-attentive processing is absent. From a first-person perspective, however, conscious states are causally effective. First-person accounts are complementary to third-person accounts. Although they can be translated into third-person accounts, they cannot be reduced to them.Max Velmans2008-09-19T14:08:54Z2011-03-11T08:57:11Zhttp://cogprints.org/id/eprint/6189This item is in the repository with the URL: http://cogprints.org/id/eprint/61892008-09-19T14:08:54ZAmniotic Fluid Ingestion Before Vaginal/Cervical Stimulation Produces a Dose-Dependent Enhancement of Analgesia and Blocks PseudopregnancyA substance in amniotic fluid (AF) and placenta has been shown to enhance analgesia produced by morphine, late pregnancy, footshock, and vaginal/cervical stimulation (VS). When morphine-induced analgesia was assessed previously, the degree of enhancement by ingestion of AF or placenta was found to be a function of the amount of analgesia being generated. We have extended these results to include the analgesia produced by VS. Analgesia induced by 75, 125, 175, or 225 g of vaginal/cervical pressure was measured in rats pretreated with 0.25 ml (by orogastric infusion) of either AF or saline. AF infusion enhanced the analgesia produced by 125 g VS, but did not affect the analgesia produced by 75, 175, or 225 g VS. Unexpectedly, we also found that infusion of AF shortly before the application of VS prevents VS-induced pseudopregnancy (PsP). Whereas the incidence of PsP following 75, 125, or 175 g VS was less than 19% and not statistically different for AF and saline pretreatments, the incidence of PsP after 225 g VS was 44% in saline-pretreated rats, but only 10% in AF-pretreated rats. Protection from the induction of pseudopregnancy, which could be caused by mechanical stimulation of the cervical area during delivery, may be an additional benefit of parturitional ingestion of placenta and amniotic fluid (placentophagia).Alexis C. Thompsonathompso@RIA.Buffalo.EDUPatricia AbbottJean C. DoerrElizabeth J. FergusonDr. Mark B. Kristalkristal@buffalo.edu1998-11-15Z2011-03-11T08:53:43Zhttp://cogprints.org/id/eprint/180This item is in the repository with the URL: http://cogprints.org/id/eprint/1801998-11-15ZEnhancement of Opioid-Mediated Analgesia: A Solution to the Enigma of PlacentophagiaTwo major consequences of placentophagia, the ingestion of afterbirth materials that occurs usually during mammalian parturition, have been uncovered in the past several years. The first is that increased contact, associated with ingesting placenta and amniotic fluid from the surface of the young, causes an accelerated onset of maternal behavior toward those young. The second, which probably has importance for a broader range of mammalian taxa than the first, is that ingestion of afterbirth materials produces enhancement of ongoing opioid-mediated analgesia. The active substance in placenta and amniotic fluid has been named POEF, for Placental Opioid-Enhancing Factor. Recent research on both consequences is summarized, with particular attention to POEF, the generalizability of the enhancement phenomenon, its locus and mode of action, and its significance for new approaches to the management of pain and addiction.Mark B. Kristal1998-11-25Z2011-03-11T08:53:39Zhttp://cogprints.org/id/eprint/71This item is in the repository with the URL: http://cogprints.org/id/eprint/711998-11-25ZInduction of maternal behavior in rats: Effects of pseudopregnancy termination and placenta-smeared pupsThe onset of maternal behavior in Long-Evans rats was examined after pseudopregnancy (PsP) termination, both with and without exogenous estrogen administration, and in response to either clean or placenta-smeared stimulus pups. Natural (spontaneous) PsP termination was as effective in hastening the onset of maternal behavior as ovariectomy plus estrogen injection. If clean foster pups were presented as soon as pseudopregnancy terminated (first proestrus or cornified smear), maternal behavior was exhibited within 2 days; placenta-smeared foster pups presented at the same time elicited maternal behavior within 2 hr. The combination of initiating maternal- behavior testing immediately after the natural termination of pseudopregnancy and proffering placenta-smeared pups apparently simulates the hormonal milieu as well as the environmental cues present at parturition, noninvasively, producing optimal conditions for the rapid induction of maternal behavior.M. A. SteuerA. C. ThompsonJ. C. DoerrM. YouakimM. B. Kristal2001-05-16Z2011-03-11T08:54:38Zhttp://cogprints.org/id/eprint/1504This item is in the repository with the URL: http://cogprints.org/id/eprint/15042001-05-16ZTestosterone administration in chicks affects responding in the presence of task irrelevant stimulus changesIntroduction:
A series of studies have shown that circulating testosterone increases the persistence with which animals search for and select a particular visual cue to respond to (as a consequence of experience with it) - and hence incur a perseveration of response towards such cues (e.g. Rogers 1971; Andrew 1972, Archer 1976; Earley & Leonard 1978).
We tested the effect of testosterone on such attention-related mechanisms by studying the effect of intradimensionsional colour changes to cues relevant and irrelevant to an operant discrimination on continuous reinforcement learning (non-reversal shifts).
Methods:
Treatment: Chicks (20 males) were given 12.5 mg testosterone enanthate im after training on a continuous reinforcement schedule of response (CRF); 19 controls received sesame oil vehicle and 8 males and 15 females had no treatment.
Testing: Birds were given A) test sessions on day 10 and 11: whereby each session consisted of 2 minutes training, 5 minutes test then 2 minutes re-training: B) 4 types of test --(i) the negative key colour changed from red to deep blue, (ii) the positive key colour changed from pale blue to green, and (iii) both key colours changed as described, and (iv) the overhead lighting changed with the introduction of a pale red filter.
Results:
1/ Treatment did not affect CRF patterns of discriminative responding.
2/ All birds decreased their response rate after a colour change.
3/ After changes on the non-reinforced key, testosterone treated birds showed significantly less attenuation of response rate.
4/ Testosterone treatment also maintained a higher rate of response (and hence fewer reinforcements) - seen especially after a change in the negative cue or overhead lighting vs. changes in the positive cue (irrelevant changes of stimulation).
5/ Testosterone treated birds also showed a shorter latency to respond after a colour change.
6/ The female birds did not differ from the males
Conclusions:
The results support a role for testosterone in the discrimination between relevant and irrelevant stimulus changes and the persistent expression of learned sets.
The fact that responding after testosterone treatment was altered by irrelevant rather than relevant stimulus changes suggests that testosterone achieves its persistence effect by enhancing the activated set or what is at the focus of attention, rather than the inhibition of features irrelevant to the ongoing situation - these provide the reference for 'what is relevant' and changes in them disturb this mechanismR.D. Oades Messent2001-06-08Z2011-03-11T08:54:40Zhttp://cogprints.org/id/eprint/1546This item is in the repository with the URL: http://cogprints.org/id/eprint/15462001-06-08ZSearch and attention: Interactions of the hippocampal-septal axis, adrenocortical and gonadal hormonesThe phenomenon of attention is treated in terms of the ability to select some sensory input channels over others by the central nervous system for further processing and behavioral organization.
Studies of birds and mammals are reviewed to illustrate two major points : -
1) The physiological interactions of the hippocampus and septum modulated by adrenocorticotropin (ACTH), adrenal and gonadal steroids have an important influence on the selective aspects of perception.
2) The theme is developed that some of these interactions mediate one of the attributes of an attention process: namely, the ability to direct attention (facilitated processing capacity)to salient stimuli to the exclusion of an irrelevant background.
Contents:
. A hippocampal role in attention --
a) Electrophysiological correlates, b) Behavioral approaches,
. Active sites for hormones --
a) Pituitary-adrenal hormones, b) Gonadal steroid hormones,
. ACTH 4-10 related molecules and behavior,
. Effects of carbohydrate active steroids,
. Physiological interactions of pituitary-adrenal hormones with the hippocampus,
. Circulating gonadal steroids and persistence --
a) Testosterone, b) Estrogen,
. Conclusions Oades1998-12-03Z2011-03-11T08:54:16Zhttp://cogprints.org/id/eprint/761This item is in the repository with the URL: http://cogprints.org/id/eprint/7611998-12-03ZLearning in escape/avoidance tasks in female rats does not vary with reproductive conditionTo determine whether the development of novel stimulus-response associations by the mother during the periparturient period is attributable to a general facilitation of learning produced by the hormonal milieu during that period, learning ability under various reproductive conditions was assessed in two tasks unrelated to the periparturitional situation. The two tasks, selected because they equalized the various groups for motivation and performance variables, were acquisition of a water-maze escape (including two reversals), and acquisition and retention of an unsignalled shuttlebox shock avoidance. The groups tested in the water maze were a midpregnant group, an immediately prepartum group, and an immediately postpartum group. In the shuttlebox, the same conditions (different rats) were compared, together with a nonpregnant estrus condition, and a nonpregnant diestrus condition. The results of both experiments indicate that although learning occurred, the characteristics of acquisition and retention were not influenced by reproductive condition.Mark B. KristalSeymour AxelrodMichael Noonan2001-06-26Z2011-03-11T08:54:43Zhttp://cogprints.org/id/eprint/1636This item is in the repository with the URL: http://cogprints.org/id/eprint/16362001-06-26ZMore persistence during task acquisition by intact vs. castrated Japanese QuailIntroduction:
In view of reports that circulating testosterone levels can lead to the persistence of the selection of previously used stimulus specifications in selective attention mechanisms (Andrew and Rogers, 1972), adult male Japanese Quail with and without circulating gonadal steroids were tested in on a match to sample task in a T-maze. As the specifications (sample) change from trial to trial, it would be predicted that testosterone would not facilitate acquisition of this task if a type of stimulus controls response, but would enhance acquisition if the steroid acts on the activation of a set.
Methods:
Treatment: Data from 13 castrated and 12 intact male Japanese Quail (Coturnix japonica) are reported.
Testing: Birds were tested with and without prior experience of simple T-maze discrimination. The main test consisted of responding to the same colour door (black or white) in one of the two arms as had been encountered in the runway (i.e. match-to-sample).
Results:
1/ Both groups of birds acquired the simple discrimination rapidly and at similar rates.
2/ On the match-to-sample task intact birds exhibited a relatively stable performance with longer response sequences, while castrates showed a more variable pattern of responding - increasing then decreasing error rates across sessions.
3/ Sequences of 3 or more responses to position or to brightness were more numerous in birds with circulating gonadal steroids.
4/ All birds showed a preference for longer sequences of response to position than to brightness .
5/ Birds with prior experience of the T-maze discrimination made fewer errors.
Conclusions:
The results support a role for testosterone in the persistent selection of familiar or learned sets for controlling response - as suggested in the introduction the effect is on the "rule" used in attention not the nature of an individual stimulus. Oades