• The greater proportion of life that a child has spent in poverty, the greater the neurological effects (See chart).
Measuring Stress
• Turner and Avison measured social stress in all socioeconomic brackets using five categories: recent life events, chronic stress, lifetime major and potentially traumatic events, discrimination stress, and symptoms of depression. They found that, “With the exception of recent life events, those in the lowest third of the socioeconomic status distribution reported higher stress levels in every category and, for essentially every category, the socioeconomic status-stress relationship is monotonic: The lower the socioeconomic status the higher the stress” (Turner and Avison, 2003).
Biological measures of stress
• Allostatic load: “a biological marker of cumulative wear and tear on the body that is caused by the mobilization of physiological systems in response to chronic environmental demands” (Evans et. al. April 2009).
• Relevant Hormones: Catecholamines such as norepinephrine, dopamine and epinephrine (adrenaline), and Glucocorticoids (mainly Cortisol)
o Control physiological responses to stress in the sympathetic nervous system like blood pressure and heart rate
o Fight-or-flight reactions
o Energy regulation: They replace energy reserves after high-stress events (restore homeostasis after high stress).
o Regulate cardiovascular system, metabolism, blood sugar, immunological responses, homeostatic functions
o Cortisol and epinephrine work together to create memories of stressful events (flashbulb memories).
• These neuroendocrine responses are important for adaptation to stressful situations, managing acute threats and maintaining homeostasis (internal stability) and allostasis.
• When these stress responses are engaged on a regular basis, they result in an allostatic load that causes the body and brain to deteriorate
• Chronic exposure to high levels of cortisol can inhibit development of the hippocampus and even stop the process of neurogenesis
Physical Factors
• Inadequate nutrition (including iron-deficiency anemia which inflicts 25% of low SES children in America)
• Substance abuse in pre- and post-natal development
• Trauma and abuse
• Exposure to environmental neurotoxins, including lead. For every 10 micrograms per deciliter increase of lead in the blood there is an estimated 2.6 decrease in IQ (Schwartz, 1994).
Psychological Factors
• Many low-SES families live in neighborhoods with high crime rates
• Job instability/issues
• The difficulties of providing for basic needs cause stress and tension within families and deeply affect children.
• Maternal depression (social interaction)
• Quality of daily care
• Less exposure to cognitive stimulation (books, toys, museums, zoos, etc.)
• Average total hours of one-on-one picture book reading for children entering Kindergarten: Low-SES children 25 hours, Middle-SES children 1000-1700 (Adams 1990).
What systems are affected by stress?
• The left Perisylvian/language system is responsible for many aspects of cognition and communication, including semantic, syntactic and phonological aspects of language, and is concentrated in the temporal and frontal areas of the left hemisphere of the brain.
• The Medial/Temporal Memory system makes it possible to retain a memory or representation after a single exposure to a stimulus (as opposed to representations that are strengthened gradually through repeated exposures). This ability relies on the hippocampus and parts of the medial temporal lobe.
• The Prefrontal/Executive system is dependent on the pre-frontal cortex and “enables flexible responding in situations where the appropriate response may not be the most routine or attractive one, or where it requires maintenance or updating of information concerning recent events” (Farah et. al. 2005).
Specific Correlations: Home Observation and Measurement of Environment (HOME) Tests, Children at ages 4 and then 8.
o Performance on Left Perisylvian/Language abilities was correlated with average cognitive stimulation (variety of toys, availability of books, language stimulation, parental speech designed to engage child, academic stimulation, behavior modeling, etc.)
o Performance on Medial temporal/Memory ability was predicted by social/emotional nurturance (warmth, affection and engagement, acceptance, emotional and verbal responsivity, encouragement of maturity, emotional climate, paternal involvement).
Conclusions:
Contributes to the discourse about childhood poverty, framing the issue as one of bioethics rather than economic opportunity
Solutions and policy implications
Saturday, May 2, 2009
Living on Earth: This Is Your Brain on Poverty
http://www.loe.org/shows/segments.htm?programID=08-P13-00009&segmentID=5
Friday, May 1, 2009
Tuesday, April 28, 2009
Understanding the origins of anxiety disorders to understand Selective Mutism
Early Childhood Behavioral Inhibition Linked to Risk of Anxiety Disorders in Adulthood:
(Evidence towards biological bases of anxiety disorders)
Selective Mutism is a widely misunderstood, ignored and under-researched childhood anxiety disorder:
The Child Who Would Not Speak A Word
(Evidence towards biological bases of anxiety disorders)
Selective Mutism is a widely misunderstood, ignored and under-researched childhood anxiety disorder:
The Child Who Would Not Speak A Word
Monday, April 20, 2009
Seeing Red, Feeling Blue
Effect of Color on Cognitive Task Performance
In the recent University of British Columbia study, researchers Mehta and Zhu explored the differences between red and blue in relation to cognitive performance. Their study involved 600 participants who performed various tasks while looking at computer screens, which displayed red, blue or neutral backgrounds. In a task of word recall, they found that participants looking at words against a red screen had a higher rate of accurate word recall than those looking at the blue or neutral screens. In another task, Meha and Shu had participants think of creative ways to use a brick. While all groups had to think of the same number of uses, judges of the study later concurred that participants in the blue screen group found more creative uses for the brick than those in either red or neutral group. From their study, Mehta and Zhu found that the color red enhances performance on tests of recall and attention to detail, while the color blue enhances performance on tests requiring imagination.
Red Enhances Human Performance
In a related study at the Durham University of England, anthropologists Russell Hill and Robert Barton found that the color red enhances performance in competitive sports. As in nature where red is connected to testosterone and masculinity, in the human world male dominance can be influenced by the wearing of red. In their study of Olympic competitions, Hill and Barton found that wearing red is consistently connected with a higher probability of winning (competitors wearing red in boxing, tae kwon do, and wrestling defeated their blue-uniformed opponents about 60% of the time). This study suggests that the evolution of sexual selection, in which red symbolizes dominance, plays a role in human response to color.
Romantic Red
In a study on male physical attraction to women at the University of Rochester, researcher Andrew Elliot and Daniela Niesta found that men who viewed photographs of women wearing red shirts perceived the women as more attractive and desirable, and were more willing to take them on a date and pay for the date, than women wearing blue shirts. Participants were not aware that the influence of color on attractiveness/attraction was being measured in the study, and they indicated that color did not play a role in their rating of the women.
Elliot and Niesta note that:
-Color is a common language within and across species
-The mere perception of color is sufficient to produce affect, cognition and behavior consistent with that meaning.
-Red carries meaning of sex and romance.
-Found in folktales, literature (The Scarlet Letter –Hawthorne), theater (A Streetcar Named Desire), red light districts and red lipstick (which has been used since Ancient Egyptians, 10,000 BCE).
-Red in animals, reddening during mating.
Color and Psychological Functioning
In another study on the effects of red by Elliot from the University of Rochester, he found that even an unconscious awareness of red in a testing scenario affects the ability of the test taker to perform. More specifically, he found that the presence of the color red during testing negatively affects performance. Elliot believes this effect is related to the meanings and specific information that red often conveys, such as a teacher’s red markings on an assignment or a red sign indicating danger. Interestingly, this study seems to contradict Hill’s study on red and Olympic competition. Elliot suggests that a distinction should be made between viewing and wearing red, for it is possible that viewing red caused the blue player to perform badly (as opposed to Hill’s theory that wearing red caused the red player to perform better.)
Spatial Color
Finally, the influence of red, blue and yellow was measured in an experiment conducted by a group of interior designers. In this experiment three identical white rooms, each 18ft x 20ft x 10ft in dimension and containing a bar with twelve white bar stools and four white computers, were “bathed” in either red, yellow or blue light. Guests were then invited to attend a cocktail party in one of the three rooms. The results showed that guests in the yellow room consumed almost twice as much food and drink than those in the other two rooms. In terms of physical interaction, guests in the blue room occupied the perimeter of the space while guests in the red and yellow rooms were far more socially interactive with each other, forming small clusters in the middle of the rooms. These findings suggest that blue may induce more antisocial behavior than red or yellow, and yellow may increase appetite.
These studies on color point to the peculiar relationship between unconscious sensory perception and cognitive functioning.
Bibliography:
“Color Study Looks at Effects of Red and Blue,” http://www.nytimes.com/2009/02/06/science/06color.html?emc=eta1
“Design: Spatial Color” http://www.contractmagazine.com/contract/esearch/article_display.jsp?vnu_content_id=1003685899
Elliot, Andrew & Marcus A. Maier. “Color and Psychological Functioning: The Effect of Red on Performance Attainment.” Journal of Experimental Psychology 136(1): 154-168.
Elliot, Andrew & Daniela Niesta. “Romantic Red: Red Enhances Men’s Attraction to Women,” Journal of Personality and Social Psychology 95(5): 1150-1164.
Hill, Russell A. & Robert A. Barton, “Psychology: Red enhances human performance in contests,” Nature 435 (293)
Mehta, R. & Zhu, R.J. “Blue or red? Exploring the effect of color on cognitive task performances,” Science 323(5918):1226-9.