Attachment Flashcards
What is attachment?
a strong, long-lasting emotional bond between two people usually an infant and a caregiver
How is attachment characterised?
by behaviours like proximity seeking, separation distress and pleasure on reunion
How does an attachment develope with a baby and a caregiver?
baby has a need - cries - need met by caregiver - trust developes - attach begins
What is reciprocity?
the actions of one person gets a response from the other person although the response is not necessarily the same and does not occur at the same time
what are alert phases?
babies signal periodically that they are ready for interaction
What is active involvement?
both babies and adults can initiate interactions
What is interactional synchrony?
behaviour is synchronised and is carrier out at the same time, mirroring each other’s behaviours
What improves the quality of an attach with mothers and babies?
high levels of interaction
What is proximity seeking?
people try to stay physically close to their attachment figure
What is separation distress?
people show signs of anxiety when an attachment figure leaves their presence
What is secure-base behaviour?
making regular contact with attachment figure to feel safe
What was the aim of Meltzoff and Moore?
investigated if infants would mirror behaviours of adults interacting with them
What was the method of Meltzoff and Moore?
x18 babies - 2-3 weeks old
controlled obvs
adult displayed 1 of 3 facial expressions - mouth opening, toungue out and pouting lips
1 hand gesture - open hand
the behaviours ands expressions of the infants were observed and recorded
What did Meltzoff and Moore find?
there was an association between the behaviour of the infant and the adult
this behaviour of the infant is innate
What does innate mean?
not learned behaviour, it is naturally installed and unconscious
What are the strengths of Meltzoff and Moore?
controlled obvs = more internally valid
filmed = check for inter-rater reliability - reliable and valid
later replication = reliable
limited to 3 expressions = greater degree of certainty - greater confidence (baby not making random faces)
support from S and E = babies can’t distinguish between people at this age - measured general infant behaviour
What are the weaknesses of Meltzoff and Moore?
not all replications succeeded = less reliable
controlled = reduces generalisability
adult was not their caregiver
What is inter-rater reliability?
meausres the degree of agreement between different people observing the same thing
What was Tronick’s ‘Still Face Experiment’ method?
filmed controlled obvs
3 stages: laster 2-3 mins
1. normal face-to-face - playing with infants normally
2. still face episode - CG stops interacting with B
3. reuinion episode - back to normal interaction
infants were 2-12 months
What did Tronick find during the Still face EPISODE?
Increase in:
-gaze aversion
-visual scanning
- pick me up gestures
-distancing behaviours = twisting/turning
-physical stress indicators = heart rate/ cortisol changes
What did the Still Face Expt show ?
babies are not passive with their interactions
they have an active role in reciprocity
shows the importance of care-giver and infant interactions
getting back into sync is important
What are the strengths of the still face exprt?
controlled obvs - internally valid
replicated - reliable and valid
filmed - checking inter-rater reliablity = increase reliablity and validity
practical implications - can help parenting
What are the weaknesses of the still face exprt?
artificial environment - possible impact on behaviour = lacks ecological validity
ethical issues - distress, showed the effects of neglect, harm to parents
What are the characteristics of Schaffer and Emerson study of the development of attachment?
longitudinal study - 2 yrs
60 infants aged 5-23 weeks
from workingclass families in Glasgow
How did Schaffer and Emerson measure attachment?
separation anxiety
stranger anxiety
What did Schaffer and Emerson find?
25-32 weeks - 50% of babies showed separation anxiety towards a specific adult (usually mum)
40 weeks - 80% showed specific attachment + 30% displayed multiple attachments
the attachments tended to be towards the caregiver who was most interactive and not the one who simply spent the most time with the infant
What was Schaffer and Emerson’s aim?
to investigate the formation of early attach. at a particular age at which they develop
What are the 4 stages of attach.?
Asocial stage
indiscriminate attachment stage
specific attachment stage
multiple attachment stage
What is the asocial stage?
birth - 2 months
babies respond to people the same way - no preferences
they can not distinguish between objects and people
What is the indiscriminate stage?
2-7 months
distinguish between people and objects
shows preference for people
no stranger or separation anxiety
reciprocity and interactional synch begin relationships
What is the specific attach stage?
forms a strong attach to a specific induvidual - who’s most interactive with baby (65% of the time the PAF is mother)
separation and stranger anxiety
What is the multiple attach stage?
occurs shortly after specific
extend attach - secondary attachments
Why do we need to know the age attach develops?
to learn how relationship affect people later in life
protects infants from harm
avoids parenting problems
What is the strength of S and E stages of attach?
good external validity - took place in their homes = behaviour is natural from baby and not affected by observers
What are the weaknesses of S and E?
the asocial stage may be due to babies having poor mobility and coordination - not able to show their attach
ethnocentric - families from same area and workingclass = problems with generalisation and population validity
1960s - lacks temporal validity
What was feild’s method of studying the role of the father?
filmed 4 month old babies
face-to-face interactions
PAF mother and fathers / SAF fathers
What did feild find on the role of the father?
the PAF mothers and Fathers spent more time interacting with the baby than the SAF
What are the strengths of Feild’s study?
controlled obvs - more internally valid
filmed - reliable and can be checked, inter-rater reliability
What is the weakness with feild’s study?
controlled - the adults may not have been acting as their usual selves
also being filmed may be acting to look better - demand characteristics
What study supports Feild’s findings?
Lamb - found that fathers who become PAF can quickly develop sensitive responsiveness and it is not limited to the mothers
What study goes against Feild’s study?
Hrdy - fathers are less able to detect low levels of infant distress which suggests that males are less suitable as a PAF
What was Grossman et al study on the role of the father?
longitudinal study - baby to teens
researchers looked at the relationship with both parents and the quality of relationships with other people
correlational study
What did Grossman find on the role of the father?
the quality of the babies attach with their mother was related to the relationship behaviour in adolescence therefore the attachment to the father is less important
however the quality of the fathers play was related to their later attach - so fathers have a different role than mores that is less to do with emotional development
What are the evaluations of Grossmans study?
correlational study - other factors may be involved
it is supported by research that have found fathers have a playmate role
How do biological sex differences have an impact on attachment?
the female hormone oestrogen is linked to caring behaviour - heightened emotional sensitivity
testosterone linked with activity - playmate
How is research on the role of the father helpful to parents?
can give advice and reduce parental anxiety
What is a ethologist?
a biologist that studies animal behaviour in their natural environment
What was Konrad Loranz’s animal study on attach?
lab study
clutch of 12 eggs - x2 groups of 6
condition 1 = hatched with goose mother
condition 2 = hatched with Lorenz
chicks followed believed mothers - known as imprinting
What did Lorenz state on imprinting and the critical period?
imprinting is genetically determined and species-specific (sexual imprinting)
both conditions are put in a box to mix - they returned to their separate mothers = imprinting is unique and irreversible
imprinting occurs during the critical period and if no attach is formed during this time - infant can not form any attachments
What are the issues with Lorenz’s study?
difficulties extrapolating to humans
overstated the importance and permenance of imprinting
Guiton et al = chicks imprinted on yellow gloves and when they spent time with peers they would engage with other chicks normally
What are the strengths of Lorenz’s study?
evidence to support - Regolin exposed chicks to moving shapes, they tried to mate with them and did not return to normal
it was influencial to other studies - Bowlby monotropic theory
What is Harlow’s animal study on attach?
aim = attach is not based on feeding
x16 rhesus monkeys in cages for 165 days with x2 mothers = cloth and wire
monkeys showed a preference for cloth mother when either mothers were feeding them
‘contact comfort’ is important
monkeys were scared with a mechanical figure - went to cloth mother for comfort
the monkeys developed abnormally: sexually abnormal and failed social interactions
if they spent time with peers before 3 months - they recovered
after 6 months - permenant damage
What are the issues with Harlow’s study?
ethical issues - harm/ permenant damage, removed from the environment
long-term effects of damage to development
EV = mothers had different heads - preference could be due to the cloth mother looking more like a monkey
What are the strengths of Harlow’s study?
didnt use humans so no one was harmed
improved understanding of child care - residential child care and fostering
extrapolation to humans - humans are similar to monkeys
strengthens S and E
supports the critical period
What is the learning theory?
abehaviourist explanation that suggests that attachments develop through classical and/or operant conditioning
What does conditioning mean?
learning
what is a stimulus?
anything present in the environment that can be picked up by the senses
what is a response?
a reaction to a stimulus
What is an unconditioned response?
a naturally occuring response to a stimulus that did not need learning
What is an unconditioned stimulus?
any stimulus that produces a response with no learning
What is a neutral stimulus?
any stimulus that does not produce a response
What is classical conditioning?
learning by the association of two stimuli
How does classical conditioning produce attachments?
unconditioned stiumli (food) = unconditioned response (pleasure)
neutral stimuli (caregiver) = no response
unconditioned stimuli + neutral stimuli = unconditioned response
conditioned stimlui (caregiver) = Conditioned response (pleasure)
attachment is formed
What is operant conditioning?
learning due to consequences
What is a positive consequence?
behaviour that is reinforced will be repeated
What is the primary reinforcer in attachment?
food as it directly satisfies hunger
What is the secondary reinforcer in attachment?
the caregiver - they provide the food
How is an attachment formed from operant conditioning?
the child seeks the person who supplies the reward which is food
What does negative mean in terms of operant conditioning?
taking away a feeling/ stimulus
What does positive mean in terms of operant conditioning?
adding a feeling or stimulus
What is negative reinforcement?
taking away something you like
What goes against the learning theory for attachment?
animal studies do not support - food is not important in attachment
S and E - less than half the attachments were to adults who feed the baby the most
findings come from animal studies - difficult to generalise to humans
Bowlby - we are born with a genetically based drive to attach, it is not learned
What does Bowlby’s monotropic theroy of attach summarise?
attach is biological and instinctive
it is an evolutionary advantage
What did bowlby say on attachment has survival value?
babies evolved to stay close to P.A.F to ensure their survival to avoid dangers
we are born with a drive to attach
What are social releasers?
babies have innate ‘cute’ behaviours that encourages attention
it activates social interactions with CG to form attach
What are the 3 key parts to Bowlby’s monotropic theory?
critical period
monotropy
internal working model
What did Bowly say on the critical period?
around 6 months - this is the sensitive period where the child is most sensitive until 2 yrs old
if mothering is delayed for 12 months - the sensitive period is useless for most children
if mothering delayed for 3yrs - the sensitive period is useless for all children
mother love is very important
What is Bowlby’s monotropy?
infants form an attach to 1 particular person - this attach is unique and most important
has two principles = the law of continuty and the low of accumulated separation
What is the law of continuity?
the more constent and perdictable a childs care, the better quality of attach
What is the law of accumulated separation?
the effects of every separation from the mother adds up
What is Bowlby’s internal working model?
a child forms a mental representation of their relationship with their PAF that serves as a model for what relationships are like
forms expectations for future relationships
affects the childs ability to be a parent
predicts that patterns of attach will be passed on through generations
What was Bailey et al research on the internal working model?
99 mothers and babies and grandmothers
standard interview procedure and strange situation
most women had the same attach to their mothers and babies
What other variable could be involved in forming attachments?
the child’s temparment - a childs genetically influenced personality = some are more sociable/ anxious than others
What are the positives of Bowlby’s monotropic theory of attachment?
studies support social releasers - babies get distressed when mum does not respond
Hazen and Shaver - evidence of the effects of the internal working model
bailey supports
What are the negatives of Bowlby’s monotropic theory of attachment?
lacks validity - Shaf and Emer = babies form multiple attach
genetic differences and temperment goes against internal working model
ignores the role of the father
mothers are blamed for babies negative development
What was the strange situations aim?
assess the quality of attachment by measuring behaviours
Who developed the strange situation?
Ainsworth
What 3 types of attach were found from the strange situation?
secure attachment
insecure-avoidanr attachment
insecure-resistant attachment
How was attachment measured by behaviours in the strange situation?
the child’s explorations
proximity to secure base (CG)
separagtion anxiety
stranger anxiety
reunion response
What is proximity-seeking?
the baby will stay close to the caregiver if a good attachment is present - they want to be close to them physically
What is a secure base?
a point of cantact that makes the baby feel safe- usually PAF
What was episode 1 of the strange situ and what did it test?
30 secs long:
Cg enters the room with baby and encourages baby to explore
testing: exploration and secure base behaviour
What was episode 2 of the strange situ and what did it test?
3 mins
stranger enters and talks to caregiver and stranger approaches baby
tests: stranger anxiety
What was episode 3 of the strange situ and what did it test?
3 mins
caregiver leaves the stranger and baby alone
tests - stranger and separation anxiety
What was episode 4 of the strange situ and what did it test?
3 mins
caregiver returns and stranger leaves
tests - exploration, secure base and reuinion behaviour
What was episode 5 of the strange situ and what did it test?
3 mins
caregiver leaves and baby is alone
tests - separation anxiety
What was episode 6 of the strange situ and what did it test?
3 mins
stranger returns
tests - stranger anxiety
What was episode 7 of the strange situ and what did it test?
3 mins
caregiver returns and reuinted with baby
tests - reuinion behaviour
Which measured behaviour is most likely to demonstrate the attachment type in the strange situ?
reuinion behaviour
secure - greet CG on return
Avoidant - may avoid CG
resistant - resists comfort
What were secure attach behaviours in the strange situ?
explores and plays happily, CG is secure base
moderate separation and stranger anxiety
greets CG for comfort on return, easily soothed by CG
What % of babies are securely attached from strange situ?
brittish - 60-75%
usa - 70%
What does secure attach show of the sensitivity of the CG?
they understand the baby and are in tune with the babys needs
what were insecure avoidant behaviours in the strange situ?
explores freely
does not show proximity needs or secure base behaviour
no reaction when CG leaves
not much stranger anxiety
little effort to contact CG on return may avoid them
no preference of stranger or CG
What % of babies were insecure avoidant attach in the strange situ?
brittish - 20-25%
usa - 20%
What does insecure avoidant attach show of the parents sensitivity?
tended to be uninterested in baby
would reject baby
self-centred and rigid in behaviour
What were the insecure resistant behaviours in the strange situ?
seek more proximity - limited exploration
very distressed on separation
high levels of stranger and separation anxiety
resists comfort on reuinion
What % of babies were insecure resistant in the strange situ?
brittish - 3%
usa - 10%
What does insecure resistant attach show of the parents sensitivity?
parenting is inconsistant eg angry and rejecting then sensitive and responsive
What were the conclusions from the strange situ?
there are different attach types - most children are securely attach which is ‘normal’ and the ‘best’
theres an association between the CG’s behaviour and the infant’s attach type
What are the positives of the strange situ?
predicts the child’s later development due to attachment
good intr-rater reliablity - been replicated and same results, researchers were able to agree on the same results
What are the negatives of the strange situ?
kagen - genetically-influenced anxiety could be a CO-V
unfamiliar situation for the child - atypical behaviours can be from this = lacks ecological validity
4th attach type - disorded/ disinhibited
unethical - distress and judgement of mothers
ethnocentric - difficulty generalising
What is a culture?
the norms and values that exist within any group of people
What are cultural variations?
the differences in norms and values that exist between people in different groups
What was Van Ijzendoorn and Kroogenburg’s study on cultural variation of attach?
meta-analysis of 32 studies, 8 countries using the strange situ
investigating the proportions of babies with different attachs across different countries and within cultures
What are the key % of secure attach from cultural variation study?
UK - 75% highest
china- 50% lowest
What are the key % of avoidant attach from cultural variation study?
japan - 5% lowest
west germany - 35% highest
What are the key % of resistant attach from cultural variation study?
UK - 3% lowest
isreal - 29% highest
japan - 27% highest
How many studies were collected from each country in the cultural variation study?
UK - 1 study
US - 18 studies
isreal - 2 studies
japan - 2 studies
west germany - 3 studies
china - 1 study
What did Van Ijzendoorn and kroogenburg find from cultural variations in attach?
secure attach was the most common in all countries
insecure resistant in induvidualist cultures - 14% similar to Ainsworths
insecure resistant in collectivist cultures - above 25%
the variations within a culture was 1.5 times greater than the variation between different cultures
What are the positives of Van ijzendoorn and Kroogenburgs study on cultural variation?
large sample size - good population validity and representation
indigenous researchers - researchers from the same cultural background as the ps
What are the negavtives of Van ijzendoorn and Kroogenburgs study on cultural variation?
most studies were American- in induvidualist cultures - low populationvalidity
meta-analysis = different researchers and environments gthe expt took place in - difficulty comparing resluts may lack internal validity
EVs = poverty, social class, environmental variables
imposed etic
What is imposed etic?
occurs when we assume an expt, will work in different cultural contexts - the results may not have the same meanings in different cultures
What is Bowlby’s theory of maternal deprivation?
’ a warm intimate and continuous relationship with a mother figure in which both find satisfaction and enjoyment’ is an essential precondition for mental health
What is maternal deprivation?
the emotional and intellectual consequences of separation between and child and their mother
What did Bowlby state on the importance of mother-love?
‘mother-love in infancy is important for mental health as are vitamins and proteins for physical health’
What is separartion from an attachment figure?
the child is not in the presence of the PAF this only becomes a problem if the child is deprived of emotional care - the child can have a carer that still cares for them so no harm is done
What happens to children experiencing separation?
relationships involving separation ( with no substitute care) becomes unstable and less predictable this emphasises the importance of a continuous relationship
if there are repeated separations before the age of 2.5 yrs oold the child may become disturbed
What does Bowlbys MDH state on the cirtical period?
first 2.5 yrs is the critical period for psychological development
if there is separation or deprivation during the critical period - the damage was inevitable
attach must occur during this time otherwise no attach will be formed
What are the effects of maternal deprivation?
mental disability (lower than normal IQ)
affectionless psychopathy (inablitiy to have deep feelings and empathy for other people)
delinquency (minor crime)
increased aggression
depression
What was Goldfarbs study for maternal deprivation?
conducted an IQ study that supports Bowlby’s MDH
found lower IQ in children who remained in institutions than those who were fostered
20 points lower IQ
What are the issues with Goldfarb’s study on IQ?
natural expt - lacks control and validity
no random allocation - more intelligent children could have been fostered
maternal deprivation can not be isolated as the cause of the IQ differences
What is the 44 theives study?
44 teenagers convicted of theft
they were interviewed and observed
17 separated from mother, 27 were not separated from their mother
12/17 separated from mother were affectionless psychopaths
correlational study
concluded that Materna Deprivation causes affectionless psychopathy and negative effects
How does lewis’s replication of the 44 theives study go against the original 44 theives study?
it included 500 young people and he found no later criminality or emotional disturbance
How does Bowlby’s study on children in hospital go against the 44 theives study?
the children were hospitalised under 4 yrs old and were visited x1/ week by their family
they did not attach to the nurses and no issues later on in life
What is the main issue with the 44 theives study?
Bowlby made the affectionless psychopathy diagnosis himself - bias as he may have altered the results to go as he expected
How does rutter’s study go against bowlby’s MDH?
bowlby failed to distinguish between deprivation and privation
privations effects are long-lasting and more serious - may have been what Bowlby investigated
How does Hodges and Tizard’s study go against bowlby’s MDH?
the children were able to recover so the theory may be invalid
What is an institution?
a place where there is contiunous long-term care eg: hospitals and orphanges
What is Hodges and Tizards study on institutions?
natural and longitudinal
65 children who had been in an institiution when they were less than 4 months old - had no oppotunity to form attach
they had good physical care and intellectual stimulation
What was Hodges and Tizards aim?
to investigate the effects of failure to form attach (privation) on later social and emtional development - testing Bowlby’s MDH that it will cause problems later in life
What did hodges and tizard find when the children were 2yrs old?
they had 24 different carers by 2 yrs old
they would run to any adult and want attention and they were cry when they left with no attach to the adult
What did hodges and tizard find when the children were 4yrs old?
they had 50 different carers by the age of 4yrs old
24 had been adopted
15 restored ( back to original homes)
26 remained in the institute
What were the differences with the restored and adopted children?
the adopted had closer attach to parents
restored had poor attachments and had behaviour issues
What were the similarities with restored and adopted children?
they would both seek attention and approval
less successful in friendships
argumentative
more likely to be bullies
less likely to be part of a crowd
What did Hozard and tizard find for attach for restored children?
4 yrs - no attach
8yr - poor attach
16 yrs - only 50% deeply attach
What did hodges and tizard conclude?
children given good quality, loving environments can recover and form attachments
goes against bowlby’s MDH - no psychopathy/ delinquency
What are the issues with hodges and Tizard’s study?
small sample due to attrition ( loss of ps during longitudinal studies) - sample may be biased as troubles children may have left
no cause and effect - natural exprt, children adopted may have been more social naturally
possibly co-v = child’s temperment
What are the positives with hodges and tizard’s expt?
natural - no ethical issues
semi-structured interview - rich in detail
How many romanian children were in rutters study? and how long were they assessed for ?
165 romanian orphans assessed from 4-25 yrs old
What was rutter’s aim with the romanian orphans study?
aim = to look at the extent to which good care would make up for poor early experiences in institutions
How did rutter assess the children in his study? and what was the control group they were compared to?
assessed physical, emotional and cognitive development
compared to a control group of 52 brittish children who were adopted to the age of 4
What did rutter find in the romanian orphans aged 11?
adopted children showed different rates of recovery that were related to the age of adoption
What did rutter find with the age of adoption and the children’s mean IQ?
there was a major drop in mean IQ when children were adopted between 6 months-2 yrs
so the age that was significant to IQ was 6 months
What did rutter find on ADHD on the romanian orphans?
it was more common in the 15 and 22-25 yr old samples
What did rutter find if the children were adopted after 6 months?
they showed signs of disinhibited attach
What is disinhibited attach?
equally friendly and affectionate towards familiar people and strangers
What are the behaviours of disinhibited attach?
attention-seeking from adults
lack of stranger anxiety
innappropriate physical contact
lack of secure base behaviour
clingy
What are the issues with disinhibited attach?
trusting anyone/ the wrong people
getting in the wrong crowd
vulnerable
more likely to be influenced
How was the romanian orphans IQ affected?
they showed signs of intellectual disability however most that were adopted before 6 months has caught up by 4yrs old
What are the issues with rutters study?
methodological issues - difficult to obtain info about the quality of care in the institutions = difficult to assess the extent of the privation
attrition - distorts results
difficult to generalise - poor conditions of the orphange, not the institution
What are the positives of rutters study?
used a range of methods to assess the children’s behaviour - semi-structured interviews and obvservations = rich in detail
real-life applications = improved the way children are cared for
What was Zeanah et al study?
95 romanian children aged 12-31 months who spent most their lives in an insitution
compared with 50 children who were not in an insititution
attach type was measured using the strange situation
there was a high % of children in the institution with disinhibited attach and little with secure attach
What was sroufe et al study on childhood relationships?
found continity between children’s ealry attach type and social competence in later childhood
What was Myron-Wilson and Smith’s study on childhood relationships?
they assessed attach and bullying behaviour
196 chiildren aged 7-11yrs old
secure attach = unlikely to be involved
avoidant = most likely to be vitims
resistant = most likely to be bullies
What was Hazan and Shaver’s study on later relationships?
published a love quiz in the American newspaper which has 3 sections:
1. current/ most important relationship
2. general love experiences
3. attach type
analysed 620 replies
What did Hazan and Shaver’s love quiz find?
secure attach - 56% = most likely to have good, long-lasting relationships
avoidant - 25% - tended to reveal jealousy and fear of intimacy
resistant - 19% = obsessive, jealous, emotional highs and lows
What are the issues with Hazen and Shaver’s love quiz?
lack of options in answers = researcher bias
ethnocentric - newspaper can target a certain group of people due to political views
difficulty generalising as ps were annonymous
desiribility bias = ps gave fake answers to be seen a certain way
answers rely on retrospective recall
What was Quinton et al’s study on parenting in early attach?
followed women who grew up in institutions and predicted that the insecure attach of the mothers would have a poor internal working model
What did Quinton find on the mothers who were in institutions?
they had extreme difficulties becoming parents as they were less sensitive to their children and less supportive
their children were most likely to be put in care or insititutions
What other factors could of been involved in Quinton’s study?
poverty
abuse
women didnt have a role model for parenting so they never really learnt how to be a parent
Evaluate the research on attach and later relationships?
some research supports the attach and the internal working model while others dont so the research is mixed so it is difficult to draw conclusions
What is the issue with attach type and later relationships research being based on self-report?
uses retrospective memory which is subject to social desirablility and demand characteristics
What type of research was done on the attach type and later relationships?
correlational - cause and effect cannot be established, other factors may be involved
What are the issues with relatedness and later relationships research?
relatedness is how we relate to others based on our attach type
people can act differently around different people with different attach types
What is the issue with the views of early experiences of attach on later relationships?
it was ‘overly deterministic’ which assumes that every ealry relationship / experience will certainly affect you later in life
What are the ethical issues with researching early childhood experiences?
involves asking people about intimate aspects of their lives which could be distressing