TOKYO (Reuters) - Japan's Nikkei stock average slid 0.8 percent on Thursday, taking aim at an 11th straight day of losses -- the longest losing streak since 1953 -- as growing economic uncertainty clouded the picture for exporters such as Sony Corp Toyota Motor Corp and other carmakers slid after Merrill Lynch downgraded General Motors saying the automaker will need $15 billion (7.5 billion pounds) to shore up liquidity and sending the company's shares tumbling, while trading houses also fell.

"Sentiment is simply very bad. There's just way too much uncertainty about where things go from here," said Yutaka Miura, senior technical analyst at Shinko Securities.

"The market has fallen for ten days, and there's a sense that at some point it should stop and recover a bit. But nobody wants to buy."

The Dow closed 20 percent below its October peak on Wednesday, hit by growing warnings of further bank losses, inflation fears and slumping consumer confidence.

Some market players said the Tokyo slide was simply a nervous response to Wall Street and shouldn't be taken too seriously, especially with key U.S. jobs data due out later on Thursday.

"Yes, people are nervous. But we'll need to wait for tonight to see if there's a real reason for this or not," said Masayoshi Okamoto, head of dealing at Jujiya Securities.

"Right now, we can't do anything."

The benchmark Nikkei had shed 122.47 points, sliding to 13,163.90. If it closes down, it will book its longest losing streak since 1953, when it slid for 12 straight days.

The broader Topix was down 1.3 percent at 1,284.63.