Effects Of Social Stimuli Research Articles

Can Facial Expressions Induce Haptic Perception?

A key challenge in haptics is designing human-human communications involving touch to facilitate positive effects on social interactions. An important consideration in designing social touch is understanding the effect of social stimuli on perception, in addition to that of a physical stimulus, because social touch always involves a partner. This study presents an experiment to demonstrate that facial expressions induce haptic perception. We developed a human-agent interaction system on a display in which participants moved the mouse cursor to click the target icon while the agent behaved as if it pulled the cursor back in the opposite direction, showing either a negative or neutral face. The perceived force during the interaction was quantified by the control display ratio using a psychophysical approach. The results show that the negative face induced a significantly greater perceived force than the neutral face. In addition, the perceived force correlated with the individual's evaluation of the facial expression; that is, the more unpleasant or aroused they perceived the facial expression to be, the more force they perceived. This study sheds light on the design of social touch performed by people who have physical or mediated contact with each other in physical space or cyberspace.

Me, myself and you: How self-consciousness influences time perception

Several investigations have shown that the processing of self-relevant information differs from processing objective information. The present study aimed to investigate the effect of social stimuli on subjective time processing. Here, social stimuli are images of an unknown male and female person and an image of participants’ self. Forty university students were tested with a time reproduction task in which they were asked to reproduce the duration of the stimulus previously presented. Images of others or themselves were used to mark the temporal intervals. Participants also performed questionnaires to evaluate the level of anxiety and depression as well as self-consciousness. A generalised linear mixed-effects model approach was adopted. Results showed that male participants with higher Private Self-Consciousness scores showed higher time perception accuracy than females. Also, female participants reported higher scores for the Public Self-Consciousness subscale than male participants. The findings are discussed in terms of social context models of how attention is solicited and arousal is generated by social stimuli, highlighting the effect of social context on subjective perception of time.

Turning Away From Averted Gazes: The Effect of Social Exclusion on Gaze Cueing.

Past studies showed increased sensitivity to other people’s gaze after social exclusion. In the present research, across two studies, we tested whether social exclusion could affect the basic cognitive phenomenon of gaze-cueing effect, namely, the tendency to redirect visual attention to the same location that other people are looking at. To this purpose, participants were socially excluded or included using the Cyberball manipulation. In Study 1, after the manipulation, participants performed a gaze-cueing task in which an individual’s gaze, oriented rightward or leftward, preceded a peripheral target stimulus requiring a simple categorization response. The gaze direction could be congruent or incongruent with the location of the target. Results revealed a reduced gaze-cueing effect for socially excluded than for socially included participants. In Study 2, where human gazes were replaced by arrow cues, such an interaction between social exclusion and trial congruency disappeared, indicating a specific effect of social stimuli. We interpreted these findings with the notion that excluded participants can perceive an averted gaze as a further sign of social exclusion, thus showing a reduced gaze-cueing effect.

Considering the context: social factors in responses to drugs in humans

Drugs are typically used in social settings. Here, we consider two factors that may contribute to this observation: (i) the presence of other people may enhance the positive mood effects of a drug, and conversely, (ii) drugs may enhance the value of social stimuli. We review evidence from controlled laboratory studies with human volunteers, which investigated either of these interactions between social factors and responses to drugs. We examine the bidirectional effects of social stimuli and single doses of alcohol, stimulants, opioids, and cannabis. All four classes of drugs interact with social contexts, but the nature of these interactions varies across drugs, and depends on whether the context is positive or negative. Alcohol and stimulant drugs enhance the attractiveness of social stimuli and the desire to socialize, and social contexts, in turn, enhance these drugs' effects. In contrast, opioids and cannabis have subtler effects on social interactions and their effects are less influenced by the presence of others. Overall, there is stronger evidence that drugs enhance positive social contexts than that they dampen the negativity of unpleasant social settings. Controlled research is needed to understand the interactions between drugs of abuse and social contexts, to model and understand the determinants of drug use outside the laboratory.

Effect of Social Stimuli on Postural Responses in Individuals with Autism Spectrum Disorder.

This study was aimed to investigate the effects of social versus non-social stimuli on postural responses in 21 boys with autism spectrum disorder (ASD) (mean age of 11.6 ± 1.5) compared with 30 typically developing (TD) boys (mean age of 11.7 ± 1.8). Postural control of children was examined while they were standing on a force plate and viewing images of an object, male face, or female face in sequence. Each image was shown in two trials and each trial lasted for 20s. Results indicated a significant interaction between group and task (p < 0.05), meaning that children with ASD but not TD children showed an increased postural sway during face tasks than during object task. Furthermore children with higher autism severity compared to those with lower severity showed an increased change in response to social stimuli (p < 0.01). It seems that the postural control of children with ASD was more affected by the social stimuli than TD children.

Effects of social stimuli on covert attentional orienting and saccaddic eye-movements during visual search

Effects of social stimuli on covert attentional orienting and saccaddic eye-movements during visual search

More excited for negative facial expressions in depression: Evidence from an event-related potential study

ObjectiveThis study aims to investigate the intensity evaluation of social stimuli in depression. MethodsTwenty-four never-disordered control participants (NC), 24 sub-clinically depressed individuals and 24 participants diagnosed with a current major depressive disorder (MDD) were recruited. All participants completed an emotional intensity evaluation task, in which they were required to judge the intensity of the facial expressions by pressing response keys, with the event-related potential (ERP) being recorded during the process. ResultsThe MDD participants had higher intensity scores for sad faces compared with the NC group, longer reaction times (RTs) for all faces compared with other groups and higher P1 and P2 amplitude for sad faces compared with other faces. The sub-clinically depressed individuals had lower intensity scores for happy and neutral faces compared with other groups, longer RTs for happy faces compared with other faces and higher P1 and P2 amplitudes for happy faces compared with sad faces. ConclusionThe findings suggest that the MDD participants are more excited for negative facial expressions, while the sub-clinically depressed individuals might have a disturbed perception for happy stimuli, which suggests a different cognitive pattern for facial expressions between MDD and sub-clinical depression. Moreover, the deep perception for sad faces is correlated with increased suicidal ideation. SignificanceThe intensity effect of social stimuli (facial expressions) was observed in sub-clinically and clinically depressed (MDD) individuals simultaneously, which might suggest that the more excited perception for negative facial expressions is a stable cognitive vulnerability possibly associated with the occurrence or recurrence of depression.

Electrocommunication signals alone are sufficient to increase neurogenesis in the brain of adult electric fish, Apteronotus leptorhynchus

Social interaction can have profound influences on the structure of the adult brain, but little is known about the precise stimulus feature found within social interaction that induces such brain plasticity. We examined the effects of social stimuli on cell addition and radial glial fiber formation in the brains of adult electric fish. These fish communicate primarily through weak, quasi-sinusoidal electric signals. Fish were housed in isolation, paired with another fish or exposed to only the electrocommunication signals of another fish for 7 days. After 3 days of exposure to these stimulus conditions, fish were injected with bromodeoxyuridine (BrdU) to mark newborn cells. We sacrificed the fish 4 days after BrdU injection and used immunohistochemistry to measure cell addition (BrdU+), the fraction of added cells that differentiated into neurons (BrdU+/NeuroTrace+) and the density of radial glia fibers (vimentin+) in the periventricular zone of the diencephalon. Fish that were exposed only to the electrocommunication signals of another fish and no other social stimuli had equivalent levels of cell addition and radial glial fiber density to fish that were housed with full social interaction and higher levels than fish housed in isolation. About 60% of the added cells differentiated into neurons; this fraction did not differ among treatment groups. Artificial sine wave electrical stimuli that mimicked electrocommunication signals were ineffective in increasing cell addition and glia fiber formation above those found in isolated fish. Thus, stimuli through a single modality are sufficient for inducing this brain plasticity, but the waveform or dynamic features of communication signals are crucial for the effect.

Social stimuli enhance phencyclidine (PCP) self-administration in rhesus monkeys

Environmental factors, including social interaction, can alter the effects of drugs of abuse on behavior. The present study was conducted to examine the effects of social stimuli on oral phencyclidine (PCP) self-administration by rhesus monkeys. Ten adult rhesus monkeys ( M. mulatta) were housed side by side in modular cages that could be configured to provide visual, auditory, and olfactory stimuli provided by another monkey located in the other side of a paired unit. During the first experiment, monkeys self-administered PCP (0.25 mg/ml) and water under concurrent fixed ratio (FR) 16 schedules of reinforcement with either a solid or a grid (social) partition separating each pair of monkeys. In the second experiment, a PCP concentration–response relationship was determined under concurrent progressive ratio (PR) schedules of reinforcement during both the solid and grid partition conditions. Under the concurrent FR 16 schedules, PCP and water self-administration were significantly higher during exposure to a cage mate through a grid partition than when a solid partition separated the monkeys. The relative reinforcing strength of PCP, as measured by PR break points, was greater during the grid partition condition compared to the solid partition condition indicated by an upward shift in the concentration–response curve. To determine whether the social stimuli provided by another monkey led to activation of the hypothalamic–pituitary–adrenal (HPA) axis, which may have evoked the increase of PCP self-administration during the grid partition condition, a third experiment was conducted to examine cortisol levels under the two housing conditions. A modest, but nonsignificant increase in cortisol levels was found upon switching from the solid to the grid partition condition. The results suggest that social stimulation among monkeys in adjoining cages leads to enhanced reinforcing strength of PCP.

Effects of artificial social stimuli on the reproductive schedule and hormone levels of yellow-eyed penguins ( Megadyptes antipodes)

The effects of social stimuli on avian reproductive behaviors such as breeding schedules and courtship behaviors are well known due to numerous field studies. However, studies that have simultaneously examined the effects of social stimuli on reproductive behavior and the mediating endocrine mechanisms have been largely restricted to captive populations, which may not be representative of free-living populations. This study, conducted over two breeding seasons, aimed to simultaneously measure the effects of experimentally increasing auditory stimuli on the breeding schedule and endocrinology (levels of total androgen, estradiol, progesterone and prolactin) on free-living yellow-eyed penguins ( Megadyptes antipodes). The yellow-eyed penguin is the least colonial of all penguins, nesting far apart from each other under dense vegetation, and, therefore, is presumed to experience much lower levels of social stimuli than other penguins. Egg laying was significantly more synchronous and tended to be earlier when birds were exposed to playbacks of the calls of conspecifics in 1 year of the study. We also found that levels of total androgen and estradiol of males in 1 year, and prolactin in another year, were proportionally higher among treated birds compared control birds that received no artificial auditory stimuli. These results show that even among supposedly solitary nesters, social stimuli could still play a role in influencing reproductive behavior and physiology. For the first time in free-living seabirds, we have demonstrated that behavioral responses to increased social stimuli are associated with hormonal changes.

The Automaticity of Affective Reactions: Stimulus Valence, Arousal, and Lateral Spatial Attention

Social psychologists have sought to understand the automaticity of affective reactions in terms of consequences for attention, evaluation, and judgment. Typically, affect is manipulated by stimulus valence, with little consideration of the role of stimulus arousal in such priming effects. The present two studies, involving 54 right–handed participants, sought to extend the case for automatic affect and sought to do so by highlighting the unique priming effects of stimulus arousal on the differential activation of the left and right hemispheres of the brain. Using affective slides as stimuli, the present two studies found that high levels of stimulus arousal, irrespective of stimulus valence, shifted attention leftward within visual space. This phenomenon extends research on automatic priming effects to lateral spatial attention and suggests an implicit spatial probe task that may be useful in future studies focused on the arousing effects of social stimuli.

Effects of Social Stimuli on Laughing and Smiling in Young Children With Angelman Syndrome

The effects of social stimuli present and absent on laughing and smiling in 2 young children with Angelman syndrome were assessed via a multielement design. Results indicated that laughing and smiling for either child was unaffected by the social stimuli assessed in the social interaction condition. Results are discussed in terms of the effects of biological variables and environmental stimuli on children with specific genetic disorders across the lifespan.

How important is social facilitation for dustbathing in laying hens?

Hens in a group usually synchronize dustbathing, such that when one hen starts to dustbathe she will often be joined by others. The sight of another hen dustbathing could thus possibly act as a stimulus increasing motivation for dustbathing, with important implications for hens in furnished cages, where the size of the dustbath normally allows only one hen to dustbathe at a time. If a hen is more motivated to dustbathe when she can see another hen dustbathing but she cannot get access to the litter since the dustbath is occupied, frustration may arise. The aim of this study was to investigate the effect of social stimuli on dustbathing motivation. Pairs of hens were exposed to one of three stimuli while being thwarted of dustbathing and they were thereafter given access to dustbathing material. The stimuli were (1) the sight of other hens dustbathing (DB-HEN), (2) the sight of a dustbath with other hens not dustbathing (NODB-HEN) and (3) the sight of a dustbath only (NO-HEN). Twelve pairs of hens were tested both deprived and non-deprived of litter in a balanced within-subject design. Irrespective of deprivation state, hens walked more and spent more time facing the stimulus in DB-HEN than in NO-HEN, and when they were not deprived they also walked more in DB-HEN than in NODB-HEN. Subsequent dustbathing behaviour when hens were given access to litter after the stimulus exposure was unaffected by the type of stimuli. We suggested that subtle effects of social stimuli on dustbathing motivation may have been masked by the effect of long litter deprivation and that it may be important for the birds to be able to join the stimulus birds to dustbathe together. For these reasons we repeated the experiment with individual hens and with a shorter litter deprivation time and a shorter stimulus exposure, after which the test hen was allowed to join the stimulus hen. Furthermore, in this second experiment hens were tested only in DB-HEN and NODB-HEN treatments. We found more displacement preening and less time facing the stimulus in DB-HEN than in NODB-HEN, but dustbathing behaviour was still unaffected by previous social stimuli. In summary, dustbathing behaviour of the test hens was not affected by seeing other hens dustbathing, but increased walking and displacement preening indicated a possible change in the motivation of test hens observing other dustbathing hens.

Effects of social stimuli on sleep in mice: non-rapid-eye-movement (NREM) sleep is promoted by aggressive interaction but not by sexual interaction

Sleep is generally considered to be a process of recovery from prior wakefulness. In addition to being affected by the duration of the waking period, sleep architecture and sleep EEG also depend on the quality of wakefulness. In the present experiment, we examined how sleep is affected by different social stimuli (social conflict and sexual interaction). Male C57BL/6J mice were placed in the cage of an aggressive dominant male or an estrous female for 1 h in the middle of the light phase. The conflict with an aggressive male had a pronounced NREM sleep-promoting effect. EEG slow wave activity, a measure of NREM sleep intensity, was increased for about 6 h and NREM sleep time was significantly increased for 12 h. REM sleep was strongly suppressed during the remainder of the light phase after the conflict, followed by a rebound later in the recovery phase. The sexual interaction, in contrast, had only mild effects. Both NREM sleep and REM sleep were somewhat suppressed shortly after the interaction. In a separate group of mice, blood samples were taken to measure prolactin and corticosterone. The results suggest that the temporary suppression of REM sleep following the social stimuli may be partly due to elevated corticosterone. The different effects of the social stimuli on NREM sleep are not easily explained by differences in the hormone responses. In conclusion, although both social conflict and sexual interaction induce a strong physiological activation, only social conflict has a strong stimulatory effect on NREM sleep mechanisms.

Olfactory stimulation enhances light-induced phase shifts in free-running activity rhythms and Fos expression in the suprachiasmatic nucleus

There is evidence to suggest that the olfactory and circadian systems are linked, functionally, and that olfactory stimuli can modulate circadian rhythms in mammals. 9,10,13,15,16,18 Furthermore, olfactory bulb removal can alter free-running rhythms in animals housed in constant darkness and can attenuate the effect of social stimuli on photic entrainment of circadian rhythms. 12,14,31–33 The mechanisms through which olfactory stimuli influence circadian rhythms are not known. One possibility is that olfactory stimuli influence circadian rhythms by modulating the activity of the circadian clock located in the hypothalamic suprachiasmatic nucleus. 22 To study this, we assessed the effect of olfactory stimulation on free-running rhythms and on photic resetting of the circadian clock in rats using phase shifts in wheel-running rhythms and expression of the transcription factor Fos in the suprachiasmatic nucleus. 23,24 We found that brief exposure to an olfactory stimulus, cedar wood essence, in the subjective day or subjective night had no effect on either free-running rhythms or Fos expression in the suprachiasmatic nucleus, but that when presented in combination with light, the odor dramatically enhanced light-induced phase shifts and Fos expression in the suprachiasmatic nucleus. Olfactory stimulation alone induced Fos expression in several structures that innervate the suprachiasmatic nucleus, pointing to ways by which stimulus information transmitted in the olfactory pathways could gain access to the suprachiasmatic nucleus to modulate photic resetting. These findings, showing that clock resetting by light can be facilitated by olfactory stimulation, point to a mechanism by which olfactory cues can modulate entrainment of circadian rhythms.

Interaction between periodic socio-sexual cues and light-dark cycles in controlling the phasing of activity rhythms in golden hamsters

Most of the previous work on the effects of social stimuli on circadian rhythms has involved the use of constant environmental conditions. In the present experiments, male golden hamsters were maintained in a light-dark cycle and exposed to females daily for 1-hr intervals. Periodic exposure to female hamsters in estrous condition resulted in advances of the males' activity onsets on subsequent days when females were not introduced (probe days). Periodic exposure to female hamsters without regard to the stage of their estrous cycle produced similar but smaller effects. With repeated exposure to female hamsters, there were decreases in the wheel-running induced during the hour when females were present (pulse hour), perhaps reflecting habituation to socio-sexual cues. These results suggest that exposure to an arousing stimulus during the normal resting time of hamsters can result in phase shifts of their endogenous circadian activity rhythms. Non-photic events may have effects on the phasing of biological ...

Effects of male courtship and gonadal steroids on pair formation, egg‐laying, and serum LH in Canvasback ducks (Aythya valisineria)

The effects of social stimuli on the reproductive physiology of female birds have been widely studied. This study examined the endocrine and behavioural responses of female Canvasbacks (Aythya valisineria) to changes in the behavioural and endocrine states of the male, as signalled by his courtship displays. Male Canvasbacks exposed to female conspecifics exhibited a variety of courtship displays which increased significantly with testosterone administration. However, the testosterone‐increased courtship displays of males did not increase female receptivity or serum LH, or stimulate reproductive development or egg‐laying in unpaired females placed with them. Females confined in cubicles within a pen that held breeding pairs and a free‐swimming flock had higher serum LH levels and laid more eggs than did females in cubicles in another pen without breeding pairs or a free‐swimming flock. This suggests that social factors, such as vocalizations from a flock and breeding pairs, may increase serum LH and egg‐laying in unpaired females. Oestradiol implants in female Canvasbacks did not elevate receptivity to courting drakes, nor did they stimulate pair formation, nesting activity, or egg‐laying behaviour. Testosterone implants in drakes and oestradiol implants in females decreased serum LH in each group. These results show that increasing the amount of courtship is not adequate to stimulate pairing behaviour or increases in reproductive hormones. Thus, our results suggest that female receptivity to male courtship may be a key determinant of pair formation and consequent synchronization of the behaviour patterns between members of a pair of wild birds. Our results may further suggest a dissociation between effects of courtship and pair formation in wild Canvasbacks.

Influence of Social Variables on the Biobehavioral Response to Separation in Rhesus Monkey Infants

Effects of social stimuli on behavioral and physiological responses to separation were examined in 4-month-old rhesus monkeys. Infants were removed from their social group under 3 counterbalanced conditions: (1) infant totally isolated from its familiar physical and social environment and placed alone in a cage for 4 days; (2) "mother in"--housing the infant in a single cage in front of its social group with mother remaining in the group; (3) "mother out"--similar situation, except that mother was removed from the group during separation. Infant behavior was recorded, and, at selected times during separation, a blood sample was obtained for analysis of plasma cortisol. Infants rarely vocalized when totally isolated, but showed high vocalization and movement in the presence of their social groups. Vocalization was transiently higher in mother-out condition than in mother-in condition. Infants never showed signs of depression. Plasma cortisol response did not differentiate between groups. Animals showed significantly high levels of plasma cortisol 3 hours following separation. These data indicate that the responses of the infant following separation are attempts to produce effective coping responses. The concepts of "protest" and "despair" are discussed as they relate to behavioral differences observed following different separation paradigms.

Social reciprocity: a review of research and educational implications.

This paper analyzes the potential contributions of research on social reciprocity to the assessment and remediation of social withdrawal among educationally handicapped preschool children. The studies reviewed clearly suggest that social reciprocity is a phenomenon that occurs during interaction among adults and normal and exceptional preschool children. It is suggested here that educational strategies designed to increase positive social interaction be based on a reciprocal conceptualization of social behavior. Such a theoretical framework is reflected in the following procedures: (a) the use of observational strategies that are sensitive to who gives what to whom, when, and with what effect; and (b) the development of intervention efforts that rely on the eliciting effect of social stimuli to accelerate the social responses of withdrawn children.

Effects of social stimuli on nest building in the zebra finch ( Poephila Guttata)

Under experimental conditions, the sight and sound of a conspecific is conducive to nest building in domesticated male grey zebra finches, but sounds from unseen nearby conspecifics seem to block this stimulating effect. The sight and sound of nearby conspecifics, in addition to a single female cagemate, suppressed the rate of nest building, lowered building efficiency, and sound from conspecifics increased general activity. It is suggested that the close proximity of conspecifics evokes a flocking tendency that interferes with nest building. If this inference is correct, one of the selective advantages in the spatial separation of flocking and nesting areas, and in the wide spacing of nests in the colony, is avoidance of social stimuli that interfere with nest building.