For a man hoping his sweet nothings will be fondly remembered by his date, speaking in a deep voice may do the trick.
A study of women's responses to high- and low-pitched voices supports the idea that our memory is attuned to things that will ensure our survival and reproductive success, the researchers wrote online Sept. 8 in the journal Memory & Cognition.
In their first experiment, researchers from the University of Aberdeen in Scotland and McMaster University in Canada had 45 women view the image of an object while listening to the name of the object spoken either by a high- or low-pitched male or female manipulated voice. The researchers used a computer program to manipulate recordings of men and women to make them more feminine (higher-pitched) or masculine (lower-pitched).
The participants were then shown two similar but not identical versions of the object and were asked to pinpoint the one they had been shown earlier. They were also asked to identify which voice they preferred.
In the second experiment, the researchers repeated the object-memory and voice-preference tests on 46 women who hadn't participated in the first experiment. This time, the researchers tested both actual male and female voices as well as the previously used manipulated voices.
The results of both experiments showed a strong preference for the low-pitched male voice and found that the women remembered objects more accurately when the item had been introduced by the deep male voice.
The same pattern was not found for female voices, suggesting a mate-selection phenomenon.
Scientists had known a guy's voice is important for mate choice, since it can indicate genetic quality, with more-masculine voices and other traits being associated with better health, the researchers said. However, a low-pitched voice also can signal behavioral traits that are undesirable in a long-term partner, such as a lack of emotional warmth, the researchers said.
The new studies "indicate for the first time, so far as we are aware, that signals from the opposite sex important for mate choice affect the accuracy of women’s memory," the researchers wrote.
The findings also suggest that, when evaluating potential partners, women seem to rely on their memories of potential partners to rapidly provide information about those partners' positive or negative characteristics and past behaviors. A low-pitched voice seems to offer an advantage, as it is more memorable to women. [Deep-Voiced Men Have More Kids]
"We think this is evidence that evolution has shaped women's ability to remember information associated with desirable men," said study researcher Kevin Allan of the University of Aberdeen. "Good memory for specific encounters with desirable men allows women to compare and evaluate men according to how they might behave in different relationship contexts ? for example, a long-term committed relationship versus a short-term uncommitted relationship."
"This would help women to pick a suitable partner, and that’s a particularly important ability to have because the costs of poor mate-choice decisions can be severe," Allan added.
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