5/28- Neurobiology of Attachment Flashcards Preview

Term 5: Behavioral Science > 5/28- Neurobiology of Attachment > Flashcards

Flashcards in 5/28- Neurobiology of Attachment Deck (30):

Molecular mechanisms underlying maternal attachment?

- Dopamine and reward processing

- Oxytocin and social affiliation


In what region is DA involved in reward processing?

When is it released?

Responsible for development of what?

- Ventral striatum

- Important in rat maternal behavior; released during mother-pup interaction

- Important factor in cognitive development and establishing reward-based contingencies


In what region is oxytocin involved?

Responsible for development of what?

- Peripheral and central brain

- Critical for the social and maternal behavior; MATERNAL CAREGIVING (critical for initiation of maternal care)--rats

- In ewes, oxytocin results in selective bonding with lamb

- Social memory (rats sniffing around new rats less upon 2nd introduction; when oxytocin blocked, demonstrated introductory behavior each time)

- Anxiolytic properties


Result of interplay in oxytocin/dopamine systems?

- Oxytocin neurons may also connect with the brain's dopamine "reward" system, resulting in changes in "long-term conditioned preferences"

- Basically, oxytocin starts things and dopamine promotes its continuation


What is attachment?

- Innate biological system to ensure protection and reproduction

- Even kids exposed to poor quality care develop attachment (although particular behavior/type of attachment differs based on quality of caregiving)

- Individual differences in attachment "security" are associated with maternal care and infant social/emotional development

- (Attachment theory originally formulated by John Browlby in 1969)


What is a typical baby's response to a predictable pattern of decreased maternal attention/neglect?

- Initially cries more

- Eventually cries much less; passive baby


What is a typical baby's response to an unpredictable pattern of decreased maternal attention/neglect?

(e.g. working multiple jobs, domestic abuse)

- Constantly irritable child (b/c sometimes crying elicits a response)


Model of maternal brain responses: what neuroendocrine pathways are involved in the development of maternal caregiving behavior?


- Mesocorticolimbic pathway (reward)

- Nigrostriatal pathway (action contingencies- you feel the reward now what do you do about it)


What are the three levels of neurodevelopment in these paths?

- Forebrain- "frontal cortex"- cognitive, analytical processing

- Limbic brain- "striatum"- emotion processing

- Midbrain- "meso/nigro"


What are 3 level components of the mesocorticolimbic dopamine pathway?


- Medial prefrontal cortex (mPFC)

- Ventral striatum

- Ventral tegmental area (VTA)


What are 3 level components of the nigrostriatal dopamine pathway?

"Action Contingencies"

- Dorsolateral prefrontal cortex (DLPFC)

- Dorsal striatum

- Substantia nigra (SN)


Where/at what level does the oxytocin pathway feed in?

Into the mesocorticolimbic pathway via the hypothalamus

- Ventral striatum

- Ventral tegmental area


What else feeds into the substantia nigra (Nigrostriatal Path)?

Ventral striatum

(So both ventral and dorsal striatums)


Study examining these neuroendocrine pathways in human mothers?

- Visit 1: pregnancy (1st time pregnant women enrolled during 3rd TM and surveyed for own pattern of attachment)

- Visit 2: videotaping (about 7 mo, studies and peripheral blood hormone levels at separated baseline, with mother interaction, and separation again)

- Visit 3: scanning (fMRI responses to pictures of baby and stranger's baby: happy, sad, neutral) - Visit 4: follow up (measuring infant attachment with strange procedure)


What does fMRI map?

Functional Magnetic Resonance Imaging

- Allows for time course of human brain activity to be imaged (as indicated by blood flow to that area)

- Stimulus -> neural pathway -> hemodynamics


What was the pattern of response for own vs. stranger's smiling baby?

Dorsal striatum (nigrostriatal)

- significant rise in signal for own vs. unknown baby's smiling face


What is the significance of a child with secure or insecure/dismissing mothers?

Measure of someone's adaptiveness to their environment; secure and insecure not necessarily "good" and "bad"

(each is good for that baby's unique environment; although not always adaptive in adulthood/long term)


Group comparisons between secure and insecure/dismissing mothers


- Increased breastfeeding duration (NS trend)

- Less mother-infant separation at 6 mo

No significant group differences with respect to:

- Maternal SES, race, education, or IQ

- Self-reported parenting stress

- Pre or post-natal depression or pscyhopathology risk

- Mother or infant temperament

- Infant development at 14 mo


Brain responses to smiling faces in secure vs. insecure/dismissing mothers?

Secure: activated many reward circuits (mesocorticolimbic path)

- Medial PFC

- Orbitofrontal cortex

- Ventral striatum

Insecure/dismissing: activated more nigrostriatal path

- Dorsolateral PFC


Brain responses to sad faces in secure vs. insecure/dismissing mothers?

Secure: still reward-based response (mesocorticolimbic path)

- Ventral striatum

Insecure/dismissing: activated more nigrostriatal path

- Dorsolateral PFC

- Anterior insula (also activated in response to physical/emotional pain and disgust)--- seeing own baby in distress activates distress in themselves (decreased ability to respond to and soothe)


Change in peripheral oxytocin with mother-infant interaction with secure vs. insecure mothers?

(Baseline -> free play -> mirror interaction -> baseline post)

Increase in oxytocin during engagement with baby for secure vs. insecure mothers


Oxytocin levels corresponded to activity of what in the brain?

- Hypothalamus/pituitary region activity

- Ventral striatum activation (again showing interplay between oxytocin and DA systems)


Modified still-face and instant affect experiment phases?

- Phase 1: normal interaction (can see but not interact)

- Phase 2: still-face; completely emotionless, but eye contact

- Phase 3: recovery (observing baby's adaptation back to normal)


What is the infants affect during these different phases of the still-face experiment?

- Negative affect: big rise during still-face, and not really recovering afterward

- Positive affect: big drop during still-face with some bounce back during recovery


What is the biggest marker of attachment pattern (secure vs. insecure mothers) in the recovery phase of the still-face experiment?

The mother expressing thoughts about the baby's feelings/what was going on in the baby's mind; mom's ability to vocalize to indicated understanding of baby's feelings/thoughts (e.g. Wasn't that strange? What do you think about that?)


Sidenote: most secure mother babies remained looking at mom while insecure would look at themselves in the mirror


What were the difference between attachment and mirroring (direct facial/gestural, vocal, and intention) for secure vs. insecure mothers during the still-face experiment?

- Facial/gestural mirroring: no difference for any of the three phases

- Vocal mirroring: no difference for any of the three phases

- Intention mirroring: BIG significant difference for the three phases (much more for secure mothers)

Classifying by this intention mirroring response correlated 73% with INFANT class (results of strange situation)


How strongly do mother and infant attachment patterns correlate?

73% match

- 65% of secure mothers have secure infants

- 71% of insecure mothers have insecure infants


Mothers with secure attachment demonstrated what hormonal/behavioral responses and to what stimuli?

- Increased DA reward responses in the brain on seeing their infant's face

- Increased oxytocin response on interacting with their infant

- More attuned vocal communication with their infant

- More likely to have children with "secure" attachment

(There is also intergenerational transmission of mother-infant attachment)


Elements of the cycle of intergenerational transmission of mother-infant attachment?

- Maternal caregiving environment: pre [stress/trauma] and postnatal

- Neuroendocrine development of infant (DA, oxytoxin)

- Infant attachment behavior (strange situation procedure)

- Ongoing environmental influences (other relationships)

- Adult attachmet patterns (adult attachment interview)

- Maternal brain and endocrine response (fMRI for DA, peripheral blood for oxytocin)

And now we're back to:

- Maternal caregiving environment....

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What is a central factor at play in many of the elements of transmissio of mother-infant attachment?

Genetic variation and epigenetic adaptation!

Shaped by:

- maternal caregiving environment

- ongoing environmental influences


- neuroendocrine development

- infant attachment behavior

- adult attachment patterns

- maternal brain and endocrine response

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