"Long before it's in the papers"
January 27, 2015


Neighborhood violence may impair kids’ thinking

June 14, 2010
Courtesy of PNAS
and World Science staff

Vi­o­lence in a child’s neigh­bor­hood may im­pair the young­ster’s abil­ity to think, even if he or she did­n’t wit­ness the vi­o­lent acts di­rect­ly, ac­cord­ing to a stu­dy.

So­ci­ol­o­gist Pat­rick Sharkey of New York Uni­vers­ity an­al­yzed Chi­ca­go hom­i­cide re­ports in com­par­i­son to da­ta from read­ing and vo­cab­u­lary as­sess­ments con­ducted dur­ing the same time frame. The aim was to meas­ure the ef­fect of lo­cal hom­i­cide on the cog­ni­tive pe­r­for­mance of a sam­ple of Chi­ca­go chil­dren aged 5 to 17. 

African-American chil­dren who were tested with­in a week af­ter a lo­cal hom­i­cide scored sub­stanti­ally low­er than peers in the same neigh­bor­hood who were as­sessed at dif­fer­ent times, Sharkey found.

The re­sults are re­ported in this week’s early on­line is­sue of the re­search jour­nal Pro­ceed­ings of the Na­tio­n­al Aca­de­my of Sci­en­ces.

The find­ings “sug­gest the need for broader rec­og­ni­tion of the im­pact that ex­treme acts of vi­o­lence have on chil­dren across a neigh­bor­hood,” Sharkey wrote.

The neg­a­tive ef­fect from vi­o­lence de­creased as the time be­tween the hom­i­cide and the as­sess­ment ex­pand­ed be­yond a week, and the ef­fect dis­ap­peared af­ter about nine days, ac­cord­ing to Sharkey. 

Pre­vi­ous re­search has found that stress can im­pair cog­ni­tive pe­r­for­mance, and that youth ex­posed to com­mun­ity vi­o­lence show el­e­vat­ed rates of symp­toms re­lat­ed to post-traumatic stress dis­or­der. 

Sharkey said his anal­y­sis is­n’t de­signed to meas­ure any pe­r­ma­nent ef­fects of ex­po­sure to vi­o­lence. But he es­ti­mat­ed that in Chi­ca­go’s most vi­o­lent neigh­bor­hoods, chil­dren’s think­ing abil­ity may be im­paired for about one week per month due to short-term ef­fects of lo­cal hom­i­cides.

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Violence in a child’s neighborhood may impair the youngster’s ability to think, even if he or she didn’t witness the violent acts directly, according to a study. Sociologist Patrick Sharkey of New York University studied Chicago homicide reports in comparison to data from reading and vocabulary assessments conducted during the same timeframe. The aim was to measure the effect of local homicide on the cognitive performance of on a sample of Chicago children aged 5 to 17. African-American children who were tested within a week after a local homicide scored substantially lower than peers in the same neighborhood who were assessed at different times, Sharkey found. The results are reported in this week’s early online issue of the research journal pnas. The findings “suggest the need for broader recognition of the impact that extreme acts of violence have on children across a neighborhood,” Sharkey wrote. The negative effect from violence decreased as the time between the homicide and the assessment expanded beyond a week, and the effect disappeared after about nine days, according to Sharkey. Previous research has shown that stress can impair cognitive performance, and that youth exposed to community violence show elevated rates of symptoms related to post-traumatic stress disorder. Sharkey said his analysis isn’t designed to measure any permanent effects of exposure to violence. But he estimated that in Chicago’s most violent neighborhoods, children’s thinking ability may be impaired for about one week per month due to short-term effects of local homicides.