螯蝦尾部的感光細胞－CPR，在過去的文獻中只知能反應光和水流刺激，且在沒有這兩種刺激的條件下，CPR神經衝動的時間序列是無特定規律的。但在保存神經網路較完整(尾扇神經束n1~n6都沒被剪除)，且也沒有光和水流刺激的條件下，發現神經訊號的時間序列成叢集分布，一秒內大概有四叢。神經訊號叢的頻率是4Hz，這頻率穩定存在，變化幅度在5%內。神經訊號叢的顯著程度(見p15)，扣除因為解剖完生理狀況越來越不好的因素外，變化幅度在±10%內，也是滿穩定的。因為剪去尾扇神經束，神經訊號叢集就會消失，推測訊號叢集是反應尾扇的某種感覺。因為訊號叢集的顯著程度，與尾扇彎曲的角度有相對應的變化，所以推測CPR利用4Hz之神經訊號叢的顯著程度來反應本體感覺。
在持續光和水流刺激的條件下，二種刺激並不會改變這個頻率，但會調整顯著程度：光照使4Hz神經訊號叢集包含的神經衝動數增加，水流刺激則降低4Hz神經訊號叢集出現的次數。綜合以上，CPR是個滿複雜的神經細胞，其神經訊號和很多生理感覺都有相關。這些感覺訊息匯集在CPR，其交互作用的方式和綜合起來代表的生理功能可需要更多的研究探討才能明瞭。

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