Influence of Oxytocin on Approach-avoidance Tendencies to Social and Non-social Stimuli
Condition: Basic Science
Study type: Interventional

Summary: 
      In this study, a randomized, placebo-controlled between-subject design is adopted to
      investigate the effect of a single-dose of intranasally administered OT on approach-avoidance
      related motivational tendencies during the processing of a series of social and non-social,
      positively and negatively valenced stimuli. To obtain a behavioral measure of
      approach-avoidance tendencies, participants will be able to control the viewing time of the
      presented stimuli, by pressing 'up' or 'down' on a keyboard. During stimulus presentation
      neurophysiological recordings will be performed to obtain a neural measure of
      approach-avoidance motivational tendencies, based on electroencephalographic recordings (EEG:
      frontal alpha asymmetry). Also assessments of autonomic arousal, based on skin conductance
      recordings will be collected.
    

Detailed description: 
      The neuropeptide oxytocin (OT) plays an important role in a wide-range of complex social
      behaviors. Recently however, the 'social' specificity of OT's action has been challenged,
      considering several observations of non-social effects of OT showing for example that OT
      reliably reduces stress also in non-social tasks.

      To account for these non-social effects of OT, the General Approach-Avoidance Hypothesis of
      OT (GAAO) has been put forward, positing that OT primarily modulates approach/ avoidance
      motivational tendencies and behaviors by impacting on the mesocorticolimbic circuitry linked
      to reward (approach) as well as cortico-amygdala circuits linked to threat (avoidance)
      (Harari-Dahan and Bernstein, 2014). Since the neural substrates underlying 'social' approach
      and avoidance are not distinct from those underlying 'non-social' approach and avoidance, the
      GAAO posits that the modulatory effects of OT should not be limited to social behaviors. In
      this view, the GAAO puts forward that OT may indeed enhance the attentional salience of many
      social cues, but not because they are social per se; but because many social stimuli are
      emotionally-evocative and personally-relevant.

      In this study, a randomized, placebo-controlled between-subject design is adopted to
      investigate the effect of a single-dose of intranasally administered OT on approach-avoidance
      related motivational tendencies during the processing of a series of social and non-social,
      positively and negatively valenced stimuli. To obtain a behavioral measure of
      approach-avoidance tendencies, participants will be able to control the viewing time of the
      presented stimuli, by pressing 'up' or 'down' on a keyboard. During stimulus presentation
      neurophysiological recordings will be performed to obtain a neural measure of
      approach-avoidance motivational tendencies, based on electroencephalographic recordings (EEG:
      frontal alpha asymmetry). Also electrodermal recordings (skin conductance) will be collected
      to obtain assessments of sympathetically-driven autonomic arousal.

      In accordance to the GAAO account, it is hypothesized that OT will reduce avoidance-related
      motivational tendencies (assessed behaviorally and using EEG), irrespective of sociality
      (i.e. similar effect towards social and non-social stimuli).

      In accordance to prior research, skin conductance responses are hypothesized to reduce after
      OT, indicating reduced sympathetically-driven autonomic arousal. On the other hand,
      considering the implicated role of sympathetic arousal in orienting responses, OT might also
      facilitate an enhancement of skin conductance responses, i.e., being reflective of OT's role
      in enhancing salience toward emotionally-evocative stimuli.
    

Intervention name(s): Oxytocin; Placebo
Intervention type(s): Drug; Drug
Intervention description(s): Syntocinon nasal spray; Placebo nasal spray
Intervention MeSH terms: Oxytocin
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Basic Science
Keywords: oxytocin; sociality; approach-avoidance motivational tendencies; EEG frontal assymmetry; skin conductance; autonomic arousal