How being perceived to be an artist boosts feelings of attraction in others.

Music production is a universal phenomenon reaching far back into our past. Given its ubiquity, evolution theorists have postulated adaptive functions for music, such as strengthening in-group cohesion, intimidating enemies, or promoting child bonding. Here, we focus on a longstanding Darwinian hypothesis, suggesting that music production evolved as a vehicle to display an individual's biological fitness in courtship competition, thus rendering musicality a sexually selected trait. We also extend this idea to visual artists. In our design, we employed different versions of naturalistic portraits that manipulated the presence or absence of visual cues suggesting that the person was an artist or a non-artist (e.g., farmer, teacher, physician). Participants rated each portrayed person's appeal on multiple scales, including attractiveness, interestingness, sympathy, and trustworthiness. Difference scores between portrait versions revealed the impact of the artistic/non-artistic visual cues. We thus tested Darwin's hypothesis on both a within-subject and within-stimulus level. In addition to this implicit approach, we collected explicit ratings on the appeal of artists versus non-artists. The results demonstrate divergent findings for both types of data, with only the explicit statements corroborating Darwin's hypothesis. We discuss this divergence in detail, along with the particular role of interestingness revealed by the implicit data.

Brain regions controlling courtship behavior in the bluehead wrasse.

Bluehead wrasses (Thalassoma bifasciatum) follow a socially controlled mechanism of sex determination. A socially dominant initial-phase (IP) female is able to transform into a new terminal-phase (TP) male if the resident TP male is no longer present. TP males display an elaborate array of courtship behaviors, including both color changes and motor behaviors. Little is known concerning the neural circuits that control male-typical courtship behaviors. This study used glutamate iontophoresis to identify regions that may be involved in courtship. Stimulation of the following brain regions elicited diverse types of color change responses, many of which appear similar to courtship color changes: the ventral telencephalon (supracommissural nucleus of the ventral telencephalon [Vs], lateral nucleus of the ventral telencephalon [Vl], ventral nucleus of the ventral telencephalon [Vv], and dorsal nucleus of the ventral telencephalon [Vd]), parts of the preoptic area (NPOmg and NPOpc), entopeduncular nucleus, habenular nucleus, and pretectal nuclei (PSi and PSm). Stimulation of two regions in the posterior thalamus (central posterior thalamic [CP] and dorsal posterior thalamic [DP]) caused movements of the pectoral fins that are similar to courtship fluttering and vibrations. Furthermore, these responses were elicited in female IP fish, indicating that circuits for sexual behaviors typical of TP males exist in females. Immunohistochemistry results revealed regions that are more active in fish that are not courting: interpeduncular nucleus, red nucleus, and ventrolateral thalamus (VL). Taken together, we propose that the telencephalic-habenular-interpeduncular pathway plays an important role in controlling and regulating courtship behaviors in TP males; in this model, in response to telencephalic input, the habenular nucleus inhibits the interpeduncular nucleus, thereby dis-inhibiting forebrain regions and promoting the expression of courtship behaviors.

Thalamus drives vocal onsets in the zebra finch courtship song.

While motor cortical circuits contain information related to specific movement parameters1, long-range inputs also have a critical role in action execution2,3. Thalamic projections can shape premotor activity2-6 and have been suggested7 to mediate the selection of short, stereotyped actions comprising more complex behaviours8. However, the mechanisms by which thalamus interacts with motor cortical circuits to execute such movement sequences remain unknown. Here we find that thalamic drive engages a specific subpopulation of premotor neurons within the zebra finch song nucleus HVC (proper name) and that these inputs are critical for the progression between vocal motor elements (that is, 'syllables'). In vivo two-photon imaging of thalamic axons in HVC showed robust song-related activity, and online perturbations of thalamic function caused song to be truncated at syllable boundaries. We used thalamic stimulation to identify a sparse set of thalamically driven neurons within HVC, representing ~15% of the premotor neurons within that network. Unexpectedly, this population of putative thalamorecipient neurons is robustly active immediately preceding syllable onset, leading to the possibility that thalamic input can initiate individual song components through selectively targeting these 'starter cells'. Our findings highlight the motor thalamus as a director of cortical dynamics in the context of an ethologically relevant behavioural sequence.

Flexible scaling and persistence of social vocal communication.

Innate vocal sounds such as laughing, screaming or crying convey one's feelings to others. In many species, including humans, scaling the amplitude and duration of vocalizations is essential for effective social communication1-3. In mice, female scent triggers male mice to emit innate courtship ultrasonic vocalizations (USVs)4,5. However, whether mice flexibly scale their vocalizations and how neural circuits are structured to generate flexibility remain largely unknown. Here we identify mouse neurons from the lateral preoptic area (LPOA) that express oestrogen receptor 1 (LPOAESR1 neurons) and, when activated, elicit the complete repertoire of USV syllables emitted during natural courtship. Neural anatomy and functional data reveal a two-step, di-synaptic circuit motif in which primary long-range inhibitory LPOAESR1 neurons relieve a clamp of local periaqueductal grey (PAG) inhibition, enabling excitatory PAG USV-gating neurons to trigger vocalizations. We find that social context shapes a wide range of USV amplitudes and bout durations. This variability is absent when PAG neurons are stimulated directly; PAG-evoked vocalizations are time-locked to neural activity and stereotypically loud. By contrast, increasing the activity of LPOAESR1 neurons scales the amplitude of vocalizations, and delaying the recovery of the inhibition clamp prolongs USV bouts. Thus, the LPOA disinhibition motif contributes to flexible loudness and the duration and persistence of bouts, which are key aspects of effective vocal social communication.

Auditory activity is diverse and widespread throughout the central brain of Drosophila.

Sensory pathways are typically studied by starting at receptor neurons and following postsynaptic neurons into the brain. However, this leads to a bias in analyses of activity toward the earliest layers of processing. Here, we present new methods for volumetric neural imaging with precise across-brain registration to characterize auditory activity throughout the entire central brain of Drosophila and make comparisons across trials, individuals and sexes. We discover that auditory activity is present in most central brain regions and in neurons responsive to other modalities. Auditory responses are temporally diverse, but the majority of activity is tuned to courtship song features. Auditory responses are stereotyped across trials and animals in early mechanosensory regions, becoming more variable at higher layers of the putative pathway, and this variability is largely independent of ongoing movements. This study highlights the power of using an unbiased, brain-wide approach for mapping the functional organization of sensory activity.

Octopamine neuron dependent aggression requires dVGLUT from dual-transmitting neurons.

Neuromodulators such as monoamines are often expressed in neurons that also release at least one fast-acting neurotransmitter. The release of a combination of transmitters provides both "classical" and "modulatory" signals that could produce diverse and/or complementary effects in associated circuits. Here, we establish that the majority of Drosophila octopamine (OA) neurons are also glutamatergic and identify the individual contributions of each neurotransmitter on sex-specific behaviors. Males without OA display low levels of aggression and high levels of inter-male courtship. Males deficient for dVGLUT solely in OA-glutamate neurons (OGNs) also exhibit a reduction in aggression, but without a concurrent increase in inter-male courtship. Within OGNs, a portion of VMAT and dVGLUT puncta differ in localization suggesting spatial differences in OA signaling. Our findings establish a previously undetermined role for dVGLUT in OA neurons and suggests that glutamate uncouples aggression from OA-dependent courtship-related behavior. These results indicate that dual neurotransmission can increase the efficacy of individual neurotransmitters while maintaining unique functions within a multi-functional social behavior neuronal network.

Neuronal plasticity in the forebrain of the male red-sided garter snake: Effect of season, low temperature dormancy, and hormonal status on dendritic spine density.

Numerous studies have reported seasonal variations in regional morphology in the brains of seasonally breeding vertebrates. These alterations of neuronal morphology and dendritic spine density appear to be an active process within specific brain nuclei that regulate seasonal behaviors. In many cases, this neural plasticity has been found to be in response to changes in circulating sex steroid hormone levels and occur within pathways essential for the control of reproductive behaviors. Male red-sided garter snakes (Thamnophis sirtalis parietalis) (RSGS) exhibit a dissociated reproductive pattern where mating is initiated at a time when the gonads and steroidogenesis are inactive. And, although circulating levels of sex steroid hormones are elevated at the initiation of courtship and mating, the only known cue found to initiate courtship behavior and mating, is an extended period of low temperature dormancy (LTD) followed by exposure to warm temperatures. This study was designed to examine the role of seasons, sex steroid hormones, and LTD on neuronal and dendritic spine density within the anterior hypothalamus-preoptic area (AHPOA), a region shown to be critical for the regulation of reproductive behaviors. In the male RSGS, the density of dendritic spines on neurons in the AHPOA was significantly greater in spring, actively courting animals, than summer or fall, non-courting animals. Animals maintained under conditions of LTD exhibited significantly increasing spine density as time maintained in LTD increased. Animals receiving either testosterone or estradiol had a significantly greater density of dendritic spines than control animals. This study offers evidence suggesting that the "set up" of the pathways controlling courtship behavior and mating in the male RSGS, is not due solely to an extended period of LTD, but that an extended period of LTD in conjunction with circulating sex steroid hormones are critical for the initiation of reproductive behavior.

Stable Sequential Activity Underlying the Maintenance of a Precisely Executed Skilled Behavior.

A vast array of motor skills can be maintained throughout life. Do these behaviors require stability of individual neuron tuning or can the output of a given circuit remain constant despite fluctuations in single cells? This question is difficult to address due to the variability inherent in most motor actions studied in the laboratory. A notable exception, however, is the courtship song of the adult zebra finch, which is a learned, highly precise motor act mediated by orderly dynamics within premotor neurons of the forebrain. By longitudinally tracking the activity of excitatory projection neurons during singing using two-photon calcium imaging, we find that both the number and the precise timing of song-related spiking events remain nearly identical over the span of several weeks to months. These findings demonstrate that learned, complex behaviors can be stabilized by maintaining precise and invariant tuning at the level of single neurons.

Behavioural tactic predicts preoptic-hypothalamic gene expression more strongly than developmental morph in fish with alternative reproductive tactics.

Reproductive success relies on the coordination of social behaviours, such as territory defence, courtship and mating. Species with extreme variation in reproductive tactics are useful models for identifying the neural mechanisms underlying social behaviour plasticity. The plainfin midshipman (Porichthys notatus) is a teleost fish with two male reproductive morphs that follow widely divergent developmental trajectories and display alternative reproductive tactics (ARTs). Type I males defend territories, court females and provide paternal care, but will resort to cuckoldry if they cannot maintain a territory. Type II males reproduce only through cuckoldry. We sought to disentangle gene expression patterns underlying behavioural tactic, in this case ARTs, from those solely reflective of developmental morph. Using RNA-sequencing, we investigated differential transcript expression in the preoptic area-anterior hypothalamus (POA-AH) of courting type I males, cuckolding type I males and cuckolding type II males. Unexpectedly, POA-AH differential expression was more strongly coupled to behavioural tactic than morph. This included a suite of transcripts implicated in hormonal regulation of vertebrate social behaviour. Our results reveal that divergent expression patterns in a conserved neuroendocrine centre known to regulate social-reproductive behaviours across vertebrate lineages may be uncoupled from developmental history to enable plasticity in the performance of reproductive tactics.

Male mice ultrasonic vocalizations enhance female sexual approach and hypothalamic kisspeptin neuron activity.

Vocal communication in animals is important for ensuring reproductive success. Male mice emit song-like "ultrasonic vocalizations (USVs)" when they encounter female mice, and females show approach to the USVs. However, it is unclear whether USVs of male mice trigger female behavioral and endocrine responses in reproduction. In this study, we first investigated the relationship between the number of deliveries in breeding pairs for 4months and USVs syllables emitted from those paired males during 3min of sexual encounter with unfamiliar female mice. There was a positive correlation between these two indices, which suggests that breeding pairs in which males could emit USVs more frequently had more offspring. Further, we examined the effect of USVs of male mice on female sexual behavior. Female mice showed more approach behavior towards vocalizing males than devocalized males. Finally, to determine whether USVs of male mice could activate the neural system governing reproductive function in female mice, the activation of kisspeptin neurons, key neurons to drive gonadotropin-releasing hormone neurons in the hypothalamus, was examined using dual-label immunocytochemistry with cAMP response element-binding protein phosphorylation (pCREB). In the arcuate nucleus (Arc), the number of kisspeptin neurons expressing pCREB significantly increased after exposure to USVs of male as compared with noise exposure group. In conclusion, our results suggest that USVs of male mice promote fertility in female mice by activating both their approaching behavior and central kisspeptin neurons.

Vibration transmission through sheet webs of hobo spiders (Eratigena agrestis) and tangle webs of western black widow spiders (Latrodectus hesperus).

Web-building spiders construct their own vibratory signaling environments. Web architecture should affect signal design, and vice versa, such that vibratory signals are transmitted with a minimum of attenuation and degradation. However, the web is the medium through which a spider senses both vibratory signals from courting males and cues produced by captured prey. Moreover, webs function not only in vibration transmission, but also in defense from predators and the elements. These multiple functions may impose conflicting selection pressures on web design. We investigated vibration transmission efficiency and accuracy through two web types with contrasting architectures: sheet webs of Eratigena agrestis (Agelenidae) and tangle webs of Latrodectus hesperus (Theridiidae). We measured vibration transmission efficiencies by playing frequency sweeps through webs with a piezoelectric vibrator and a loudspeaker, recording the resulting web vibrations at several locations on each web using a laser Doppler vibrometer. Transmission efficiencies through both web types were highly variable, with within-web variation greater than among-web variation. There was little difference in transmission efficiencies of longitudinal and transverse vibrations. The inconsistent transmission of specific frequencies through webs suggests that parameters other than frequency are most important in allowing these spiders to distinguish between vibrations of prey and courting males.

Physiological effects of L-theanine on Drosophila melanogaster.

Green tea has been consumed as the most popular drink in East Asia for centuries, and is believed to have a wide range of health benefits. L-Theanine, the major component of the free amino acids in green tea, has been reported to display neuronal protection and tumor inhibition in vitro, but its physiological effects on animal development and behavior remain elusive. In this report, we used Drosophila melanogaster, the fruit fly, as a model organism to investigate the physiological effects of L-theanine. Flies were fed with three different concentrations of theanine as a dietary supplement after eclosion, and were examined for a variety of physiological parameters at different time points. We found theanine treatment results in significantly increased locomotion and courtship ability, and decreased resistance against wet and dry starvation in males, but not in females. Furthermore, theanine application diminished UV tolerance in females, but not in males. However, we did not perceive distinguishable effect of theanine on animal development, life span, weight, and tolerance of heat and anoxia. This work represents the first comprehensive physiological investigation of L-theanine at the whole animal level, and shall shed light on the mechanistic study of theanine in the future.

Hypothalamic neurogenesis in the adult brain.

Adult-born new neurons are continuously added to the hippocampus and the olfactory bulb to serve aspects of learning and perceptual functions. Recent evidence establishes a third neurogenic niche in the ventral hypothalamic parenchyma surrounding the third ventricle that ensures the plasticity of specific brain circuits to stabilize physiological functions such as the energy-balance regulatory system. Hypothalamic lesion studies have demonstrated that regions associated with reproduction-related functions are also capable of recruiting newborn neurons to restore physiological functions and courtship behavior. Induced by lesion or other stimulation, elevated neurotrophic factors trigger neurogenic cascades that contribute to remodeling of certain neural circuits to meet specific transient functions. This insight raises the possibility that event-specific changes, such as increased GnRH, may be mediated by courtship-sensitive neurotrophic factors. We will discuss the potentially integral and ubiquitous roles of neurogenesis in physiological and biological phenomena, roles that await future experimental exploration.

Romantic relationships and health among African American young adults: linking patterns of relationship quality over time to changes in physical and mental health.

With trends in delayed marriage, scholars have begun to explore how a wide range of romantic relationships contribute to health. Although a welcome shift, this largely cross-sectional work ignores potential (in)stability in relationship supports and stressors thought to affect health. Using Family and Community Health Study data on 634 African American young adults, we extend this work by demonstrating the value of a holistic, multidimensional assessment of relationship quality for understanding the link between relationships and health. In addition, however, we also show that there is substantial instability in both the presence and quality of romantic relationships during the transition to adulthood. Importantly, particular patterns of instability are uniquely associated with changes in mental and physical health. Given persistent racial inequalities across both relationships and health, such findings prove theoretically and practically important. In particular, they highlight the need for more contextualized, life course-sensitive approaches in future work.

Seasonal changes in courtship behavior, plasma androgen levels and in hypothalamic aromatase immunoreactivity in male free-living European starlings (Sturnus vulgaris).

In songbirds from temperate latitudes, singing during spring has an essential role in mate attraction, while during the non-breeding season it is connected to territorial aggression and/or maintaining dominance hierarchies or flock cohesion. Courtship behavior is regulated by plasma testosterone (T) levels. Other androgens, like dehydroepiandrosterone (DHEA) could be responsible for aggression. The aromatization of androgens in the brain is an essential step in mediating their effects on behavior. Our goal was to determine whether the seasonal changes in male courtship behavior (measured by average song bout length and wing-waving/flicking) are related to seasonal changes in androgen activity (measured by plasma T, DHEA levels) and aromatase (ARO) immunoreactivity in the preoptic area/medial preoptic nucleus (POA/POM) of free-living male starlings. DHEA increased during pair formation, decreased at nesting and remained at low levels. The number of ARO cells - in line with the T levels - increased during the courtship and nesting periods, but outside the breeding season it was low. Song bout length showed a similar pattern, namely the peak was reached during the courtship period, and after that males stopped singing when chicks started to hatch. Short and fast wing-flicking and wing-waving behavior was observed only during the breading season. Summarizing, we have found that song bout length of male starlings changes parallel with plasma T levels and ARO immunoreactivity in the POA/POM. Furthermore, DHEA levels were low during the sexually inactive period which suggests that other mechanisms could be involved in the aggressive non-courtship behavior/vocalization in these birds.

Teen magazines as educational texts on dating violence: the $2.99 approach.

This study analyzed the portrayal of dating violence in teen magazines published in the United States. Such an investigation is important because previous research indicates that dating violence is a serious problem facing adolescents, teen magazines overemphasize the importance of romantic relationships, and teens who read this genre frequently or for education/advice are especially susceptible to its messages. Results indicated that although teen magazines do frame dating violence as a cultural problem, they are much more likely to utilize an individual frame that emphasizes the victim. Results were discussed as they apply to the responsibilities of professionals working with adolescents.

Evidence that female endocrine state influences catecholamine responses to male courtship song in European starlings.

Little is known about the neural control of female responses to male courtship. Female European starlings in breeding condition with high concentrations of estrogen select mates based on variation in song and approach nest boxes broadcasting male song. In contrast, outside of the breeding season (when estrogen is low) females do not display the same response to male song. The catecholamines dopamine and norepinephrine regulate behaviors important for mate choice such as arousal, attention, sexual motivation, and goal-directed approach responses, suggesting a role for catecholamines in female responses to male song. In the present study, treating females with a dopamine agonist inhibited, whereas an antagonist stimulated female interest in nest boxes broadcasting male song. In a second study immunocytochemistry was used to examine the distribution of the phosphorylated (i.e., active) form of tyrosine hydroxylase (pTH), the rate-limiting enzyme for catecholamine synthesis. Exposure to male song in breeding condition females reduced pTH density in brain regions involved in social behavior (lateral septum, ventromedial nucleus of the hypothalamus) and a region involved in visual processing (nucleus of Edinger-Westphal) but not song control regions. Opposite patterns of pTH labeling densities were observed in the same regions in response to song in non-breeding condition females. pTH in the ventral tegmental area was also affected by song and female endocrine condition. Overall, the present data support an inhibitory role for dopamine in female responses to courtship and suggest that endocrine state and catecholamines interact to regulate this behavior.

Aromatase inhibition abolishes courtship behaviours in the ring dove (Streptopelia risoria) and reduces androgen and progesterone receptors in the hypothalamus and anterior pituitary gland.

The aim of this study was to determine in the ring dove, the effects of aromatase inhibition on the expression of aggressive courtship and nest-soliciting behaviours in relation to the distribution of cells containing immunoreactive androgen (AR) and progesterone (PR) receptor in the hypothalamus and pituitary gland. Isolated sexually experienced ring doves were transferred in opposite sex pairs to individual breeding cages, and then injected with the aromatase inhibitor, fadrozole (four males and four females), or saline vehicle (four males and four females) for 3 days at 12 hourly intervals. Saline-injected control males displayed aggressive courtship behaviours (bow-cooing and hop-charging) and nest-soliciting throughout the study, and control females displayed nest-soliciting. By day 3, fadrozole treatment resulted in the disappearance of all these behaviours and in a decrease or disappearance of AR and PR in the anterior pituitary gland, and in the nucleus preopticus paraventricularis magnocellularis (PPM), nucleus preopticus medialis (POM), nucleus hypothalami lateralis posterioris (PLH), and ventral, lateral and dorsal nucleus tuberalis in the hypothalamus (VTu, LTu, DTu). In the nucleus preopticus anterior (POA), fadrozole treatment decreased AR in both sexes and decreased PR in females but not in males. Cells containing co-localized nuclear AR and PR were found in all hypothalamic areas examined, and in the anterior pituitary gland. Fadrozole is suggested to reduce the local availability of estrogen required indirectly for the induction of AR, and except in cells containing PR in the male POA, for the direct induction of PR. It is suggested that aggressive courtship behaviour is terminated by "cross talk" between aromatase-independent PR and aromatase-dependent AR co-localized in neurons in the POA. Aromatase-independent PR may increase in the male POA in response to visual cues provided by a partner. Aromatase-dependent PR in the POM, and basal hypothalamus may play a role in the facilitatory effect of progesterone on estrogen-induced nest-orientated behaviours.

Vasotocin treatment inhibits courtship in male zebra finches; concomitant androgen treatment inhibits this effect.

Zebra finches evolved in arid areas of Australia. Their reproduction is stimulated by water availability, which is unpredictable. Cheng (Poult. Sci. Rev. 5 (1993) 37) hypothesized that the primary mechanism controlling reproduction in species relying on unpredictable cues should be inhibitory. The onset of stimulatory environmental conditions terminates the inhibition, allowing rapid initiation of reproduction. As the primary hormone regulating water balance in birds, arginine vasotocin (AVT) appears a likely candidate to modulate reproduction in finches. Drought conditions cause sustained AVT release, which in other species inhibits androgen production. To determine whether increased AVT inhibits reproductive behavior, intact males were tested with females and divided into three groups matched for courtship behavior. Osmotic minipumps containing (a) saline, (b) 264 ng AVT, or (c) 1320 ng AVT in saline were implanted subcutaneously and males tested 48 h later. AVT-treated males socialized with females, but the high dose significantly reduced singing and courtship displays. To determine whether AVT acted by depressing androgen secretion, additional males were given subcutaneous androgen implants and divided into two groups matched for courtship behavior. Males were then implanted with minipumps containing (a) saline or (b) the high AVT dose. Males treated with AVT plus androgen showed no deficits in courtship behavior. These data suggest that AVT secretion during periods of drought may inhibit reproduction by inhibiting androgen production. Inhibition of reproductive behavior by AVT may be a more general phenomenon. Large quantities of AVT or, in mammals the closely-related peptide vasopressin (VP), are released when animals are stressed, and high levels of AVT/VP may inhibit reproductive behavior. The extremely short half-life of these peptides means that once proximal factors become more favorable, the gonads should rapidly be released from the peptides' inhibitory actions.