Watching television more than two hours a day early in life can lead to attention problems later in adolescence¹, according to a study released on Tuesday.

Watching television more than two hours a day early in life can lead to attention problems later in adolescence, according to a study released on Tuesday.

The roughly 40 percent increase in attention problems among heavy TV viewers was observed in both boys and girls.

The link was established by a long-term study of the habits and behaviors of more than 1,000 children born in Dunedin, New Zealand, between April 1972 and March 1973.

The children aged² 5 to 11 watched an average of 2.05 hours of weekday television. From age 13 to 15, time spent in front of the tube rose to an average of 3.1 hours a day.

"Those who watched more than two hours, and particularly those who watched more than three hours, of television per day during childhood had above-average symptoms of attention problems in adolescence," Carl Landhuis of the University of Otago in Dunedin wrote in his report, published in the journal Pediatrics.

Young children who watched a lot of television were more likely to continue the habit as they got older, but even if they did not the damage was done, the report said.

"This suggests that the effects of childhood viewing on attention may be long lasting," Landhuis wrote.

Landhuis offered several possible explanations for the association.

One was that the rapid scene changes common to many TV programs may over stimulate³ the developing brain of a young child, and could make reality seem boring by comparison.

"Hence, children who watch a lot of television may become less tolerant of slower-paced and more mundane⁴ tasks, such as school work," he wrote.

It was also possible that TV viewing may supplant⁵ other activities that promote concentration, such as reading, games, sports and play, he said.

Previous studies have linked the sedentary habit of TV watching among children to obesity⁶ and diabetes⁷, and another study in the same journal cited the poor nutritional⁸ content of the overwhelming majority of food products advertised on the top-rated US. children's television shows.

Up to 98 percent of the TV ads promoting food products that were directed at children aged 2 through 11 "were high in either fat, sugar, or sodium," wrote Lisa Powell of the University of Illinois in Chicago.

据本周二公布的一项研究结果，儿童时期每天看电视超过两小时会导致青少年时期出现注意力问题。

调查发现，无论男孩女孩，老看电视的人的注意力问题多出约40%。

研究人员对1972年4月至1973年3月在新西兰达尼丁出生的1000多个孩子的行为习惯进行了一项长期调查，得出了上述结论。

调查发现，孩子在5岁至11岁期间平均每天看电视的时间为2.05个小时。而到了13岁至15岁，每天看电视的时间则增加到了3.1个小时。

达尼丁奥塔哥大学的卡尔•兰德胡易斯在研究报告中提到：“儿童时期每天看电视超过两个小时，尤其是超过三个小时的人青少年时期出现的注意力问题超过平均水平。”该研究报告在《儿科》期刊上发表。

随着年龄的增长，儿童时期老看电视的人很可能会继续这一习惯，即使他们不再这样，但影响已经造成了。

兰德胡易斯在报告中写道：“这说明儿童时期老看电视会对注意力造成长期影响。”

兰德胡易斯为这一结论提供了以下几种可能的解释：

一是很多电视节目中的快速画面切换可能会过度刺激孩子们正在发育的大脑，与电视中的画面相比，现实可能会让他们觉得没意思。

他在报告中说：“因此，老看电视的孩子对节奏较慢和较“世俗”的任务，如做家庭作业，可能没什么耐心。”

还有一种可能是，看电视可能会占用其它有助于培养注意力的活动的时间，如，看书、做游戏、运动及玩耍等。

此前有研究表明，儿童看电视所养成的久坐习惯会导致肥胖或糖尿病，该期刊中的另一项研究指出，美国收视率最高的儿童电视节目中广告的绝大多数食品营养价值都很低。

芝加哥伊利诺斯州大学的莉莎•鲍威尔在研究报告中说：“多达98%的、针对两岁至11岁儿童的广告食品‘要么脂肪含量高、要么糖份多或者含盐量高’。”