Gentle sound stimulation, also known as pink noise, may significantly enhance deep sleep in older adults and improve their ability to recall words, a new study has found.
Deep sleep is critical for memory consolidation. However, beginning in middle age, deep sleep decreases substantially, which scientists believe contributes to memory loss in aging. The sound stimulation significantly enhanced deep sleep in participants and their scores on a memory test. “This is an innovative, simple and safe non-medication approach that may help improve brain health,” said Phyllis Zee, professor at Northwestern University in the US. “This is a potential tool for enhancing memory in older populations and attenuating normal age-related memory decline,” said Zee.
Zee and a team of researchers gathered 13 adults, 60 and older, and monitored their sleep in a lab for two nights. On both nights, the participants took a memory test, went to bed while wearing headphones and a special cap, and took another memory test in the morning. But without the participants’ awareness, researchers only played pink noise into the headphones on one night. More specifically, they timed the sounds to match the participants’ slow-wave oscillations. During deep sleep, brain waves slow to about one oscillation per second, compared to about ten oscillations per second during wakefulness. The system they employed in the study allowed the team to deliver a low burst of pink noise at the “precise moment” when the participants’ slow waves rose — a pattern that is unique to each person.
The study found that participants’ slow waves increased after the night of sound stimulation, suggesting that they were getting more deep sleep. And on the morning after hearing pink noise, they performed three times better on memory tests than they did after sleeping without any sound stimulation.
Previous research showed pink noise during deep sleep could improve memory consolidation in young people. But it has not been tested in older adults. The new study targeted older individuals and used a novel sound system that increased the effectiveness of the sound stimulation in older populations.
The study was a relatively small one, so further research is needed to confirm its findings and to study how longer-term use of pink noise affects sleep. But Northwestern has taken steps to patent the researchers’ technology, which seems to have hit upon a way to stimulate slow waves at the right moment. The team hopes to develop an affordable device that people can use at home, from the comfort of their beds.
【小题1】The new study mainly reveals that _____.| A．deep sleep consolidates old adults’ memory |
| B．pink noise boosts memory among the elderly |
| C．sleep disorders play a key role in memory loss |
| D．sound stimulation increases the length of sleep |
| A．worsening | B．reversing | C．slowing down | D．bringing about |
| A．It employed a sound system programmed in step with brain waves. |
| B．It compared the effects on older adults and on younger populations. |
| C．It repeated the experiment several times without the participants’ notice. |
| D．It adjusted the participants’ slow-wave oscillations to match the stimulations. |
| A．may put old adults in risk in the long run |
| B．has the potential to be applied in practice |
| C．requires an innovative and affordable device |
| D．needs Northwestern’s patent for confirmation |
