為了解催產素在雌鼠腦中扮演著什麼樣的角色,紐約大學醫學院(New York University School of Medicine)的科學家首先探究母鼠對鼠寶寶呼喚的一般反應。為躲避掠食者,母鼠定期會變換巢穴的位置,而當鼠寶寶被不小心被落在窩外時,牠們便會發出超音波的哭聲。當母鼠聽見這樣的哭聲時,即跑回將落下的鼠寶寶撿回窩裡。過去研究顯示,母鼠就算是聽到非自己親生的鼠寶寶哭聲時,也會有反應並且靠近發出哭聲的寶寶。大部份的處女鼠則漠不關心鼠寶寶尋求幫助的哭聲。然而,被與母鼠及其孩子一起豢養或是注射了催產素的處女鼠則會去撿回嚎啕大哭的鼠寶寶。
這個發現使得此研究團隊的領導者,神經科學家 Robert Froemke懷疑催產素協助「將少女腦轉換成母性腦」,但這個轉換是如何發生的呢?過去研究顯示,母鼠對於寶寶鼠痛苦哭聲的記憶儲存在大腦中負責處理聲音的聽覺區。 研究人員在雙側的聽覺區發現了催產素的受器,以及製造催產素的神經元!且左側聽覺區的催產素受器特別多,顯示這一區的腦專門在辨識社會性的訊息。Froemke認為這十分類似人腦處理語言的腦側化情形 ,因為大部份人的左大腦半球是負責管控語言的。
Robert Liu,一位未參與此研究的艾默理大學神經科學家認為這是個十分具開創性的發現,他表示:「我們過去不曾思考催產素在腦中可能扮演的角色,然而這現在卻是此領域中最令人興奮的事」。這被稱為「母愛賀爾蒙」的激素,也被認為很有可能同時參與了腦中嗅覺及聽覺訊息的處理,而如果這是真的的話,那麼催產素很有可能帶給自閉症和產後憂鬱症等某些疾病更佳的治療。
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