Scientists have recently found that there are two brain pathways involved how we perceive our own thumping heart.

科学家们最近发现，大脑中有两种方式感知我们自己的心跳。

Hearing Our Heartbeat

The other day my 3-year old God son and I were pillow fighting when he sat down, panting, and said with surprise, "I can feel my heart beating!" Sometimes it takes little kids to remind us just how amazing our bodies are.

Scientists believe that an area of the brain, the interior and anterior cingulate cortex, is involved in what is known as interoceptive awareness-the awareness of our own physiological sensations, like a heart beating deep within your body.

But recent research from the University of Iowa has shown that we can also use another separate pathway when we consciously experience our internal physical states.

This second pathway, they believe, runs from the skin to the somatosensory cortex, which is the part of the brain that maps the external body.

The results came from a study with a neurological patient, "Roger," who has been studied in the lab for 15 years, after suffering brain damage from herpes simplex encephalitis. Roger has nearly complete damage to his insula and anterior cingulate cortex, but his somatosensory cortex is completely intact.

Researchers injected 11 healthy male subjects and Roger with a synthetic form of adrenaline, which made their pulses' shoot up by 25 beats per minute.

Roger felt his heartbeat as clearly as the other subjects, although slightly delayed. Researchers suspected Roger's brain registered his heartbeats from the surface of his chest wall and from blood vessels pulsating under his skin. To confirm this they anesthetized his skin in specific areas, and administered adrenaline again.

The healthy subjects felt their heartbeat, as before. But Roger felt nothing.

This study suggests that both brain pathways are involved in interoceptive awareness, which can cover anything from a panic attack, to the sick-feeling of rejection, to a pounding heart from an afternoon pillow fight.

倾听我们的心跳

有一天我三岁的教子和我玩儿枕头大战，当他歇下来的时候，他气喘吁吁惊奇说道： "我能听到我的心跳！" 有时候，我们需要小孩子提醒才想起我们的身体是多么的神奇。

科学家们认为，大脑中的内扣带皮质和前扣带皮质与我们所知的内感受性知觉有关，内感受知觉是我们对自己身体感受的一种感知，比如我们体内的心跳。

但是最近来自衣阿华大学（University of Iowa）的研究表明，当我们有意识经历我们内部身体情况的时候，我们也能使用另外一种独立的感知途径。

科学家们相信，这第二种感知途径从皮肤延伸到体感皮质---体感皮质是大脑中对外部身体提供信息的结构。

该研究结果来自于对一名神经患者"Roger"的研究，Roger由于患单纯疱疹病毒性脑炎致使其大脑受到了损害。研究人员在实验室对Roger进行了15年的研究。Roger的内扣带皮质和前扣带皮质几乎完全损坏，但是他的体感皮质完好无损。

研究人员向Roger和11名健康的受试者注射了一种合成肾上腺激素，这种激素能让他们的脉搏跳动频率每分钟增加25次。

Roger和其他受试者一样，也能清晰地感受到他的心跳，只不过他感受到的时间稍晚一点儿。研究人员推测Roger的大脑从他的胸腔壁和皮肤下跳动的血管记录了他的心跳。为了证实这一点，研究人员对Roger特定皮肤的部位进行了麻醉，然后再注射肾上腺激素。

健康的受试者仍然能感受到他们的心跳。但是Roger什么也感受不到。

该项研究表明，在内感受性知觉中，大脑中的两种感知途径都参与了。内感受性知觉包括许多感觉，这些感觉包括从恐慌、被拒后的沮丧心情、到午后枕头大战之余的怦怦心跳。

Vocabulary:

Perceive:感知

Thump:强有力的跳动；重击

Pant:气喘吁吁

Interior cingulate cortex:内扣带皮质

Aanterior cingulate cortex:前扣带皮质

Interoceptive awareness:内感受性知觉

Physiological:生理的

Sensation:感觉；感受

Consciously:有意地

Internal:内部的

Somatosensory cortex:体感皮质

Neurological:神经性的

Herpes simplex encephalitis:单纯疱疹病毒性脑炎

Intact:原封不动的；未受损伤的

Inject:注射

Adrenaline:肾上腺激素

Delay:延迟

Suspect:推测；猜测

Pulsate: 跳动

Anesthetize: 麻醉

Specific: 特定的