Date post: | 17-Aug-2015 |
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Pr. Harold Mouras
Professor in Neuroscience
School of Psychology – Amiens University, France
WAS 2015 Meeting – Singapore, July 25th
2015
• unify different observa2on’s levels: psychological, neural…
• different studies presented by “sphere”: central; peripheral
Affective neurosciences of social links
Since two decades, modern neuroimaging techniques allowed to observe neural processes involved in percep2ve, cogni2ve or motor paradigms
Two exponen2ally developing fields
Affec2ve neurosciences (Panksepp, 2003)
Social neurosciences (Insel et Fernald,
2004)
Within psychology and neuroscience, correspondences have been shown between cogni2ve and neural systems involved in:
• ac2on’s produc2on • ac2on’s percep2on by an observer
• mirror neurons: originally a “motor” concep2on
• to feel an emo2on during the observa2on of another person involves a physiological synchrony between the protagonists (Levenson & Ruef, 1992)
• rela2onships between individuals obey to a mo2va2onal component of inter-‐aQrac2on (posi2ve or nega2ve)
• this concep2on has spread to the emo2ons and mo2va2on
• BeQer understanding of emo2onal processes (neural and psychological) in contexts integra2ng a rela2onal dimension (and concepts such as the self, the other and their representa2ons)
Sexual mo2va2on and affilia2on: a specific and precise working model and func2onal context to explore the neural and psychological underpinnings of mo2vated social rela2onships
• Explore through two outstanding results the recent advances in neural and bodily processes involved in sexual behavior
• General contribu2on for social neurosciences
Neural correlates
• In ethology: sexual behavior is a well-‐recognized goal-‐directed behavior
• The involvement of the brain is quite obvious (neuropharmacology etc…)
• Its explora2on by func2onal neuroimaging remains recent (2000)
• Several theories of emo2on consider as central bodily reac2ons for the emo2on itself (Damasio for example)
• Few simultaneously measured penile and neural responses
• Arnow et al. (2002): • first simultaneous fMRI (brain)/ penile plethymosgraphy (erec2on) study
• No brain areas found by classical subtrac2ve analyses vs an insular/claustrum network correlated with penile response
Early responses Inverted paQerns
Low levels Volumetric measure ++
Late levels Volumetric = Circum.
• MR-‐compa2ble volumetric penile plethysmograph: study the correla2on between the cerebral and erec2le responses
• Explore the temporal rela2on between them
Mouras et al. (2008). NeuroImage
Highest: when cerebral responses preceded by 20 seconds the erec2le response
• Mirror neurons seem also involved in the physiological component coding, which seems an2cipatory
• The physiological synchrony between protagonists seems central
Motor correlates
• Numerous studies on the link between motor and affec2ve behavioral components
• Automa2c responses driven by emo2onal s2muli: role in specie's survival -‐> behavioral adapta2on regarding the func2onal context
Bidimensional concept of emo2ons and mo2va2ons (IAPS; Lang et al., 2008): approach-‐avoidance type behavior
Unpleasant Fear Mu2la2on
Pleasant Family Ero2c
• use of sport sciences techniques to measure body’s center of pressure’s displacement varia2ons (Gurfinkel 1973; Winter et al., 1990)
• Emo2on conceptualized as an ac2on’s tendency
• Numerous studies reported an influence of emo2on on all steps of motor processes (Bradley, 1992; Hälbig, 2011)
• Ac2on’s tendency is central in sexual mo2va2on which is induced by an appropriate target
• Example: Bindra defines the Central Mo2ve State as an hypothe2cal group of neural processes promo2ng goal-‐directed ac2ons for specific s2muli
• Frijda: mo2va2on will induce an ac2ons’ sequence • Both et al., 2004: Interest and tendinous reflexes increases linearly with arousal of sexual videos as compared to neutral ones
• S2ns et al., 2007: Gait’s ini2a2on faster in response to smiling than angry face
• Naugle et al., 2010: difference of walking speed only from the second step for sexual s2muli as compared to unpleasant ones
• Gélat et al., 2011: in incongruent task (move towards an unpleasant s2m.) -‐> interference with cogni2ve resources creates an early freezing
• Posturography: not much used in mo2va2onal condi2ons
• Emo2ons could influence decision through pavlovian’s system ac2on: Ly et al. (2014): • Angry faces slow down approach behavior
• Individual differences in emo2onal bias predicted those in body freezing
• Freezing has been observed in anxious situa2ons
• some2mes in front of disgus2ng s2muli (S2ns et al.) along with HR decelera2on
• No varia2on of the COP has been previously reported in front of sexually explicit s2muli (Hillman et al., 2004; S2ns et al., 2007)
• 33 healthy males included in a block-‐design paradigm • Three videos defining three experimental condi2ons: humoir (H); neutral (N); sexually explicit (S) • Experimental run: white screen (20s) ; 9 experimental blocks (50s); white screen (20s)
• Motor correlates: BIOPAC system interfaced with a SATEL force plasorm • Analyses: calcula2on of postural indexes such as body's Center Of Pressure (COP) AN and ML direc2ons; area under the curve; sway magnitude; SD of the displacement
dimension of the stimuli and not by their valence [43]. Sexual stimuli are the most arousing sti-muli of the category of positive emotional and motivational stimuli. Our results can be inter-preted in the light of a recent review of the literature focusing on the concept of freezing asfreezing is usually considered to be thisa threat-related defense strategy [44]. At first sight, ourbehavioral responses appear to be incongruous in response to motivating stimuli. Haagenarset al. [44] reported immobility as the main characteristic of other types of response, such as ori-enting or tonic immobility, behavioral inhibition and reported that immobility may be difficultto differentiate from freezing. According to these authors, freezing may have been inconsistent-ly reported as orienting, avoidance, vigilance, attentive immobility and anxiety. The results ofthe present study would therefore be consistent with the development of a freezing-like strategy
Fig 1. Mean ± SD for postural indices as a function of the stimulus (A) Amplitude of the sway of the COP in the mediolateral direction (Amp [COP]-ML) (B)Amplitude of the sway of the COP in the anteroposterior direction (Amp [COP]-AP) (C) Standard displacement of the COP in the mediolateral direction (SD[COP]-ML) (D) Standard displacement of the COP in the anteroposterior direction (SD [COP]-AP) (E) Area encompassed by displacements of the COP(COP-Area) Significant differences are indicated as follows: * p < 0.05, ** p<0.01 when comparing stimulus.
doi:10.1371/journal.pone.0127097.g001
Freezing and Sexual Behavior
PLOS ONE | DOI:10.1371/journal.pone.0127097 May 20, 2015 6 / 10
S condi2on as compared to the N –condi2on: • Significant effect on SD COP-‐AP and SD COP-‐ML indexes
• Significant effect on Amp-‐COP ML index: lower displacement amplitude in the ML direc2on
• Differen2al modula2on in sexual condi2on of motor correlates as compared to others physiological measures • Results not in accordance with the primary hypothesis of an approach-‐type behavior in response to sexual s2muli • Support the idea of an early freezing in response to sexual s2muli
• Horslen et al., 2011: freezing modula2on by the arousal dimension of the s2muli
• Haagenars et al., 2014: freezing could be the primary component of behavioral responses such as tonic immobility and/or behavioral inhibi2on
• Early freezing (1 to 2 s) responses in response to unpleasant films (record temporal courses ++) • Early freezing response: necessary for dissimula2on and ac2on’s prepara2on (Mc Naughton et al., 2004) • Paradoxical aspect of sexual response: postural responses tend to demonstrate early anxious aspects of the sexual response
In accordance with previous studies repor2ng ac2on’s prepara2on • through freezing (Griebel et al., 1996; Kalin et al., 1997) • Involving supplementary cogni2ve resources recruitment (slower rea2on 2mes in experimental tasks; Mokros A et al., 2010; Sanwla et al., 2009 etc…)
Fachinew et al., 2006 « their baby and family pictures may have elicited a predisposi2on to social bonding and that the pre-‐ac2va2on of muscles involved in the antero-‐posterior displacement could reflect prepara2on for processes like aQachement and reduc2on of social distance »
• Sexual mo2va2on: an excellent func2onal context to study the neural, motor and physiological correlates of mo2vates social rela2onships • Our studies demonstrates the complexity (par2cularly temporal) of the motor and neural correlates
http://www.socioaffectiveneuroscipsychol.net/ Special issues on the question of sexuality
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