* TSX down 13.84 points, or 0.1 pct, at 12,220.11 * Financials, materials shares down; energy shares up By Claire Sibonney TORONTO, Oct 12 (Reuters) - Toronto's main stock index was slightly lower on Friday morning as negative market reaction to quarterly results from a pair of major U.S. banks added to prevailing concerns about slowing global economic growth. Shares of JPMorgan Chase and Wells Fargo & Co both fell after they released their results, even though JPMorgan posted record profits, prompting Canadian financials to follow suit, dropping 0.2 percent. Bank of Nova Scotia was down 0.3 percent at C$53.31, and Toronto-Dominion Bank was 0.2 percent lower at C$80.85. "Everybody is focusing more on the uncertainty created not only by Europe, but the U.S. fiscal cliff, the upcoming elections in November, all of those I think are larger than the earnings expectations," said John Ing, president of Maison Placements Canada. Helping to push the index lower was a 0.4 percent drop in its materials sector on weak metals and grain prices. Barrick Gold dropped 1 percent to C$38.65, and Potash Corp was down 0.9 percent to C$41.04. At 10:33 a.m. (1233 GMT), the Toronto Stock Exchange's S&P/TSX composite index was down 13.84 points, or 0.1 percent, at 12,220.11. Energy shares limited the fall, edging up 0.1 percent as U.S. crude futures advanced. The rise in oil prices, however, was dampened by a report from the International Energy Agency (IEA) that said ample supply from North America and Iraq, coupled with declining global demand, could lead to an easing of oil prices over the next five years. Canadian Natural Resources rose 0.9 percent to C$30.28, and Suncor Energy climbed 0.2 percent to C$32.39. Also helping sentiment, Thomson Reuters/University of Michigan data showed U.S. consumer sentiment rose unexpectedly in October to its highest level in five years as optimism about the overall economy improved.