Social and Emotional Laterality (Chapter 5)

Social and Emotional Laterality (Chapter 5)

1. Localzation Theory of brain functioning

   • Right brain
     • Social and emotional functions dominated here - The right cortex is more densely connected w/subcortical regions than is the left. - Develop earlier and guided by emotional and bodily reactions - Responds to negative emotional stimuli prior to conscious awareness - Organize & stores many early social & emotional experiences that can emerge in later relationships
     • Its dominance for bodily and emotional functioning free the left cortex to attend more environmental and abstract reasoning
       • A growth spurt during the first 18 months- attachment relationship w/caregiver
         • OMPFC along w/ACC & Insula cortices- 1st to develop
           • Higher level input into bodily homeostasis affected by social relationships and network of attachment
             • Shape during high school via experience
   • Left Brain
     • - Its ability to filter & inhibit input from the allows dissociation between the cognitive and emotional processing 

2. Emotions

   • Right hemisphere
     • Appears biased negative emotions (withdrawal)
       • - Depression decrease left frontal activation - Stress, anxiety, fear, trauma & pain activate the RH
   • Left hemisphere
     • Appears biased positive emotions (approach)
   • Amygdala
     • - Kids w/early adversity show less activation of it when ask to OBSERVE negative & fearful faces - Kids w/early adversity show increase activation of it when ask to LABEL negative & fearful faces
     • Not process the angry/fearful faces as threatening stimuli to the same degree as others
       • Avoidance of threatening stimuli not require active coping efforts
   • Limbic system
     • Rats
       • Greater amygdala response to stress & <in hippocampal arborization
     • Humans
       • Stress decreases hippocampal volume in adults and increases in children

3. Plasticity

   • Experience-Dependent
     • Brain structure and restructure by interaction w/social and natural environment
       • Interaction % mother & child= Potent determinant of brain development and adaptation
         • - Early interaction build neural networks &amp; establish biological set points (long lasting) - Mothers brain is also stimulated &amp; grow w/the child -MATERNAL PLASTICITY Parents vs nonparents different brain activation when response to crying and laugh of infants
   • Findings from rats
     • Having children enriches, stimulates & challenge the brain
       • Impoverish env w/offsprings = rats of enriched env
         • Hippocampus & Hypothalamus grow

4. Maternal Behavior

   • Cortisol and Maternal depression
     • 'FETAL PROGRAMMING' model: experiences in the uterus may impact the physiology underlying the relationship functioning
   • Into biological structure
     • Mainly thru: construction of networks such as OMPFC, ACC, Insula & Amygdala
       • Growth of glucocorticoid - help regulate effects of stress

5. Building the brain

   • Mother's behavior correlated w/infant's biological changes
   • Regulating affect
     • Psychological and physical well-being depend on our ability to regulate emotions
       • Child needs to be protected from intense, prolonged and overwhelming affective states
   • Social Engagement (VAGUS) system
     • Vagus nerve: the longest cranial nerve; contains motor (efferent) and sensory (afferent) fibers
       • Arise from the brain, passes neck thorax to the abdomen
         • When no threat regulates digestion, growth
           • When face a challenge, decrease in vagal activation, facilitates sympathetic arousal, high energy output, fight/flight response
             • Vagal tone
               • Higher
                 • Self-regulation - Emotion regulation - Higher performance under stress
               • Lower
                 • Irritability - Distractibility - Depressed mood