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Social Stimuli (social + stimulus)
Selected AbstractsDevelopmental changes in responsiveness to parents and unfamiliar adults in a monogamous monkey (Callicebus moloch)AMERICAN JOURNAL OF PRIMATOLOGY, Issue 2 2002D.J. Mayeaux Abstract Titi monkeys (Callicebus moloch) are monogamous New World primates that are characteristically found in family-type groups consisting of a mated adult pair and one or two young. The factors maintaining the small size of these groups are not known. Based on observations of free-ranging and captive families, parental aggression toward older offspring seems unlikely to play a significant role. Maturing individuals themselves, however, could undergo behavioral changes that weaken ties to their natal group. These might include waning of affiliative relations with parents, or subtle forms of aversion. Independent of such changes, increasing interest in unfamiliar conspecifics could be a factor. We examined these possibilities in the present study by assessing changes in social behavior and social preferences from initial ambulatory independence (6 months) through reproductive maturity (24 months) in a combined cross-sectional/longitudinal study of 21 captive titi monkeys living with their parents. Responses to both parents and to an unfamiliar adult heterosexual pair, a single unfamiliar adult male, and a single unfamiliar adult female were observed when subjects were given a choice between parents and strangers presented simultaneously or as the only social incentive. Social stimuli were at opposite ends of a 16.8-m-long test corridor. Subjects could move freely about the corridor for 5 min with each configuration of social stimuli. They stayed closer to parents than to strangers at all ages. Responsiveness to strangers increased with age and suggested growing ambivalence, particularly toward the male stranger. As they approached 24 months of age, male subjects showed a dramatic increase in the frequency and intensity of agonistic behaviors toward male strangers, behaviors that were rarely directed toward female strangers or parents. Waning of attraction to parents may be less important in dispersal from the natal group than changing reactions to strangers. Am. J. Primatol. 58:71,89, 2002. © 2002 Wiley-Liss, Inc. [source] Social influences on mammalian circadian rhythms: animal and human studiesBIOLOGICAL REVIEWS, Issue 3 2004Ralph E. Mistlberger ABSTRACT While light is considered the dominant stimulus for entraining (synchronizing) mammalian circadian rhythms to local environmental time, social stimuli are also widely cited as,zeitgebers'(time-cues). This review critically assesses the evidence for social influences on mammalian circadian rhythms, and possible mechanisms of action. Social stimuli may affect circadian behavioural programmes by regulating the phase and period of circadian clocks (i.e. a zeitgeber action, either direct or by conditioning to photic zeitgebers), by influencing daily patterns of light exposure or modulating light input to the clock, or by associative learning processes that utilize circadian time as a discriminative or conditioned stimulus. There is good evidence that social stimuli can act as zeitgebers. In several species maternal signals are the primary zeitgeber in utero and prior to weaning. Adults of some species can also be phase shifted or entrained by single or periodic social interactions, but these effects are often weak, and appear to be mediated by social stimulation of arousal. There is no strong evidence yet for sensory-specific nonphotic inputs to the clock. The circadian phase-dependence of clock resetting to social stimuli or arousal (the,nonphotic'phase response curve, PRC), where known, is distinct from that to light and similar in diurnal and nocturnal animals. There is some evidence that induction of arousal can modulate light input to the clock, but no studies yet of whether social stimuli can shift the clock by conditioning to photic cues, or be incorporated into the circadian programme by associative learning. In humans, social zeitgebers appear weak by comparison with light. In temporal isolation or under weak light-dark cycles, humans may ignore social cues and free-run independently, although cases of mutual synchrony among two or more group-housed individuals have been reported. Social cues may affect circadian timing by controlling sleep-wake states, but the phase of entrainment observed to fixed sleep-wake schedules in dim light is consistent with photic mediation (scheduled variations in behavioural state necessarily create daily light-dark cycles unless subjects are housed in constant dark or have no eyes). By contrast, discrete exercise sessions can induce phase shifts consistent with the nonphotic PRC observed in animal studies. The best evidence for social entrainment in humans is from a few totally blind subjects who synchronize to the 24 h day, or to near-24 h sleep-wake schedules under laboratory conditions. However, the critical entraining stimuli have not yet been identified, and there are no reported cases yet of social entrainment in bilaterally enucleated blind subjects. The role of social zeitgebers in mammalian behavioural ecology, their mechanisms of action, and their utility for manipulating circadian rhythms in humans, remains to be more fully elaborated. [source] Maternal and littermate deprivation disrupts maternal behavior and social-learning of food preference in adulthood: Tactile stimulation, nest odor, and social rearing prevent these effectsDEVELOPMENTAL PSYCHOBIOLOGY, Issue 3 2006Angel I. Melo Abstract Maternal and littermate (social) separation, through artificial rearing (AR), disrupts the development of subsequent maternal behavior and social learning in rats. The addition of maternal-licking-like stimulation during AR, partially reverses some of these effects. However, little is know about the role of social stimuli from littermates and nest odors during the preweaning period, in the development of the adult maternal behavior and social learning. The purpose of this study was to examine the effects of peer- and peer-and-odor rearing on the development of maternal behavior and social learning in rats. Female pups were reared with mothers (mother reared,MR) or without mothers (AR) from postnatal day (PND) 3. AR rats received three different treatments: (1) AR-CONTROL group received minimal tactile stimulation, (2) AR-ODOR females received exposure to maternal nest material inside the AR-isolation-cup environment, (3) AR-SOCIAL group was reared in the cup with maternal nest material and a conspecific of the same-age and same-sex and received additional tactile stimulation. MR females were reared by their mothers in the nest and with conspecifics. In adulthood, rats were tested for maternal behavior towards their own pups and in a social learning task. Results confirm our previous report that AR impairs performance of maternal behavior and the development of a social food preference. Furthermore, social cues from a littermate, in combination with tactile stimulation and the nest odor, reversed the negative effects of complete isolation (AR-CONTROL) on some of the above behaviors. Exposure to the odor alone also had effects on some of these olfactory-mediated behaviors. These studies indicate that social stimulation from littermates during the preweaning period, in combination with odor from the nest and tactile stimulation, contributes to the development of affiliative behaviors. © 2006 Wiley Periodicals, Inc. Dev Psyshobiol 48: 209,219, 2006. [source] Doublecortin as a marker of adult neuroplasticity in the canary song control nucleus HVCEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 4 2008Jacques Balthazart Abstract It is established that in songbirds the size of several brain song control nuclei varies seasonally, based on changes in cell size, dendritic branching and, in nucleus HVC, the incorporation of newborn neurons. In the developing and adult mammalian brain, the protein doublecortin (DCX) is expressed in postmitotic neurons and, as a part of the microtubule machinery, required for neuronal migration. We recently showed that in adult canaries, DCX-immunoreactive (ir) cells are present throughout the telencephalon, but the link between DCX and the active neurogenesis observed in songbirds remained uncertain. We demonstrate here that DCX labels recently born cells in the canary telencephalon and that, in parallel with changes in HVC volume, the number of DCX-ir cells is increased specifically in the HVC of testosterone-treated males compared with castrates, and in castrated testosterone-treated males paired with a female as compared with males paired with another male. The numbers of elongated DCX-ir cells (presumptive migrating neurons) and round multipolar DCX-ir cells (differentiating neurons) were also affected by the sex of the subjects and their photoperiodic condition (photosensitive vs photostimulated vs photorefractory). Thus, in canaries the endocrine state, as well as the social or photoperiodic condition independently of variation in steroid hormone action, affects the number of cells expressing a protein involved in neuronal migration specifically in brain areas that incorporate new neurons in the telencephalon. The DCX gene may be one of the targets by which testosterone and social stimuli induce seasonal changes in the volume of song nuclei. [source] Oxytocin and estrogen receptor , and , knockout mice provide discriminably different odor cues in behavioral assaysGENES, BRAIN AND BEHAVIOR, Issue 4 2004M. Kavaliers Social behavior involves both the recognition and production of social cues. Mice with selective deletion (knockout) of either the gene for oxytocin (OT) or genes for the estrogen receptor (ER) -, or -, display impaired social recognition. In this study we demonstrate that these gene knockout mice also provide discriminably different social stimuli in behavioral assays. In an odor choice test, which is a measure of social interest and discrimination, outbred female Swiss-Webster mice discriminated the urine odors of male knockouts (KO: OTKO, ,ERKO, ,ERKO) from the odors of their wildtype littermates (WT: OTWT, ,ERWT, ,ERWT). Females showed marked initial choices of the urine odors of OTWT and ,ERWT males over those of OTKO and ,ERKO males, and ,ERKO males over ,ERWT males. The odors of OTKO and ,ERKO males also induced aversive, analgesic responses, with the odors of WTs having no significant effects. Odors of both the ,ERWT and ,ERKO males induced aversive, analgesic responses, with the odors of the WT inducing significantly greater analgesia. The odors of restraint stressed WT and KO males also elicited analgesia with, again, females displaying significantly greater responses to the odors of stressed OTKO and ,ERKO males than their WTs, and significantly lower analgesia to the odors of stressed ,ERKO than ,ERWT males. These findings show that the KO mice are discriminated from their WTs on the basis of odor and that the various KOs differ in the relative attractiveness/aversiveness of their odors. Therefore, in behavioral assays one causal route by which gene inactivation alters the social behavior of knockout mice may be mediated through the partners' modified responses to their odors. [source] Developmental changes in responsiveness to parents and unfamiliar adults in a monogamous monkey (Callicebus moloch)AMERICAN JOURNAL OF PRIMATOLOGY, Issue 2 2002D.J. Mayeaux Abstract Titi monkeys (Callicebus moloch) are monogamous New World primates that are characteristically found in family-type groups consisting of a mated adult pair and one or two young. The factors maintaining the small size of these groups are not known. Based on observations of free-ranging and captive families, parental aggression toward older offspring seems unlikely to play a significant role. Maturing individuals themselves, however, could undergo behavioral changes that weaken ties to their natal group. These might include waning of affiliative relations with parents, or subtle forms of aversion. Independent of such changes, increasing interest in unfamiliar conspecifics could be a factor. We examined these possibilities in the present study by assessing changes in social behavior and social preferences from initial ambulatory independence (6 months) through reproductive maturity (24 months) in a combined cross-sectional/longitudinal study of 21 captive titi monkeys living with their parents. Responses to both parents and to an unfamiliar adult heterosexual pair, a single unfamiliar adult male, and a single unfamiliar adult female were observed when subjects were given a choice between parents and strangers presented simultaneously or as the only social incentive. Social stimuli were at opposite ends of a 16.8-m-long test corridor. Subjects could move freely about the corridor for 5 min with each configuration of social stimuli. They stayed closer to parents than to strangers at all ages. Responsiveness to strangers increased with age and suggested growing ambivalence, particularly toward the male stranger. As they approached 24 months of age, male subjects showed a dramatic increase in the frequency and intensity of agonistic behaviors toward male strangers, behaviors that were rarely directed toward female strangers or parents. Waning of attraction to parents may be less important in dispersal from the natal group than changing reactions to strangers. Am. J. Primatol. 58:71,89, 2002. © 2002 Wiley-Liss, Inc. [source] Reward processing in autismAUTISM RESEARCH, Issue 2 2010Ashley A. Scott-Van Zeeland Abstract The social motivation hypothesis of autism posits that infants with autism do not experience social stimuli as rewarding, thereby leading to a cascade of potentially negative consequences for later development. While possible downstream effects of this hypothesis such as altered face and voice processing have been examined, there has not been a direct investigation of social reward processing in autism. Here we use functional magnetic resonance imaging to examine social and monetary rewarded implicit learning in children with and without autism spectrum disorders (ASD). Sixteen males with ASD and sixteen age- and IQ-matched typically developing (TD) males were scanned while performing two versions of a rewarded implicit learning task. In addition to examining responses to reward, we investigated the neural circuitry supporting rewarded learning and the relationship between these factors and social development. We found diminished neural responses to both social and monetary rewards in ASD, with a pronounced reduction in response to social rewards (SR). Children with ASD also demonstrated a further deficit in frontostriatal response during social, but not monetary, rewarded learning. Moreover, we show a relationship between ventral striatum activity and social reciprocity in TD children. Together, these data support the hypothesis that children with ASD have diminished neural responses to SR, and that this deficit relates to social learning impairments. [source] Social influences on mammalian circadian rhythms: animal and human studiesBIOLOGICAL REVIEWS, Issue 3 2004Ralph E. Mistlberger ABSTRACT While light is considered the dominant stimulus for entraining (synchronizing) mammalian circadian rhythms to local environmental time, social stimuli are also widely cited as,zeitgebers'(time-cues). This review critically assesses the evidence for social influences on mammalian circadian rhythms, and possible mechanisms of action. Social stimuli may affect circadian behavioural programmes by regulating the phase and period of circadian clocks (i.e. a zeitgeber action, either direct or by conditioning to photic zeitgebers), by influencing daily patterns of light exposure or modulating light input to the clock, or by associative learning processes that utilize circadian time as a discriminative or conditioned stimulus. There is good evidence that social stimuli can act as zeitgebers. In several species maternal signals are the primary zeitgeber in utero and prior to weaning. Adults of some species can also be phase shifted or entrained by single or periodic social interactions, but these effects are often weak, and appear to be mediated by social stimulation of arousal. There is no strong evidence yet for sensory-specific nonphotic inputs to the clock. The circadian phase-dependence of clock resetting to social stimuli or arousal (the,nonphotic'phase response curve, PRC), where known, is distinct from that to light and similar in diurnal and nocturnal animals. There is some evidence that induction of arousal can modulate light input to the clock, but no studies yet of whether social stimuli can shift the clock by conditioning to photic cues, or be incorporated into the circadian programme by associative learning. In humans, social zeitgebers appear weak by comparison with light. In temporal isolation or under weak light-dark cycles, humans may ignore social cues and free-run independently, although cases of mutual synchrony among two or more group-housed individuals have been reported. Social cues may affect circadian timing by controlling sleep-wake states, but the phase of entrainment observed to fixed sleep-wake schedules in dim light is consistent with photic mediation (scheduled variations in behavioural state necessarily create daily light-dark cycles unless subjects are housed in constant dark or have no eyes). By contrast, discrete exercise sessions can induce phase shifts consistent with the nonphotic PRC observed in animal studies. The best evidence for social entrainment in humans is from a few totally blind subjects who synchronize to the 24 h day, or to near-24 h sleep-wake schedules under laboratory conditions. However, the critical entraining stimuli have not yet been identified, and there are no reported cases yet of social entrainment in bilaterally enucleated blind subjects. The role of social zeitgebers in mammalian behavioural ecology, their mechanisms of action, and their utility for manipulating circadian rhythms in humans, remains to be more fully elaborated. [source] | ||||||||||