* Global growth fears continue to dominate markets
* ECB policymakers, Fed's Yellen scheduled to speak
* Investors looking to central banks to stabilise market
By Marius Zaharia
LONDON, Oct 17 (Reuters) - Lower-rated euro zone bonds were under selling pressure on Friday as the regional economy's deteriorating prospects focused investor attention on any hints of monetary easing from ECB policymakers.
Four European Central Bank policymakers, as well as Federal Reserve chief Janet Yellen, are scheduled to speak during the day.
Deflation hit five euro zone countries in September, including Italy and Spain, while a string of surprisingly weak German economic data and a deteriorating rating outlook for France has had investors wondering where growth will come from.
"The main reasons behind the recent market movement include increasing concerns regarding slowing growth and deflation risks facing the global economy, and in particular Europe's economy," said Giordano Lombardo, group CIO for Pioneer Investments.
"Markets are...becoming more and more nervous on the effective will of the ECB to intervene with unconventional measures."
Benoit Coeure kicked off a series of public appearances on Friday by European Central Bank policymakers, with Vitor Constancio, Ewald Nowotny and Jens Weidmann also due to speak.
Spanish, Italian and Portuguese 10-year yields were 3-4 basis points higher at 2.25 percent, 2.62 percent, and 3.54 percent, respectively.
This week's rise took them roughly 25-50 basis points above their record lows.
They remain well below highs above 7 percent hit at the height of the euro zone crisis, but the speed at which yields have risen this week has brought back memories of crisis years.
Greek and Italian yields are on track for their biggest weekly rise since 2012.
The ECB was key in easing the crisis in that year when it introduced the Outright Monetary Transaction programme - effectively a promise to buy government bonds of troubled countries if they were in a bailout and committed to reforms.
That programme was never used, but brought down yields significantly. The latest leg in the two-year bond rally also has to do with hopes of ECB bond-buying, this time as a monetary policy tool to inject large amounts of money into the economy.
This instrument is known as quantitative easing, or QE, and has been deployed by other big central banks, like the Fed, the Bank of England or the Bank of Japan.
Traders say these instruments still have an impact on the market and that they could lead to more stable periods as investors second-guess their impulse to sell.