1、全句整体上是一般疑问句,因此,结尾应该是问号.
Does it happen right away as the brain receives signals from the eyes or a little later as the brain’s high-level thinking processes get involved【?】
2、由于疑问句用了助动词,句子原来成分的位置有变化,划分成分比较凌乱和困难,最好将所给句子还原成陈述句.整体句子结构：
【It 主语】【happens 谓语】【 right away状语】【 as the brain receives signals from the eyes 时间状语从句】or 【a little later 状语】【 as the brain’s high-level thinking processes get involved.状语从句】
3、从句结构：
as 【the brain主语】【 receives谓语】【 signals宾语】【 from the eyes定语】
as【 the brain’s high-level thinking processes主语】【 get involved谓语】
4、全句翻译：
它在大脑接收到来自眼睛的信号时立刻就发生还是稍后大脑的高级思维过程也参与其中的时间（才发生）?
祝你开心如意!