Lashley was aware of the physiological nature of the problem and discussed it in considerable detail. He advanced an argument against chain association which has been referred to frequently but which, by itself, could be explained away by proposing certain theoretical constructs. He argued that the motor events in certain fast skills, such as playing the piano or snapping the fingers, follow one another at such a fast rate that there would be no time for neural messages to go from the periphery to the brain and there elicit the next response. From Table 3.4 we may deduce that this argument also holds to a certain extent for the rate of speech movements. But auditory feedback greatly speeds up reafferentation and thus minimizes the time problem even though it does not eliminate it. Theoretically, however, this aspect of the problem is not unsurmountable if we assume, as we believe mediation theory does, that the sequential association is between events entirely contained within the brain. Suppose nervous event A triggered nervous event B, both in the cortex of the left hemisphere; now the conduction time between these cortical events would be negligible. This assumption is neurologically naïve (see Chapter Five) and it also does not overcome other, more fundamental objections to the associational model, namely to explain every speaker’s ability to anticipate events yet to come.
Lashley察覺這個問題有生物學的本質，並且作了詳盡的討論。他提出一個論證來反對鏈型組合，鏈型組合雖然時常被提及，但是其本身可以藉由某些理論建構的提出來作解釋以反駁之。他主張在某些高速技巧中的運動事件(像是彈鋼琴或是彈手指)，以這麼高的速率一個接一個發生，以至於神經訊息不會有時間從周邊回到大腦而能夠引發下一個反應。從表3.4我們可以推論出這樣的論點在某程度上對於說話速度的速率也能成立。但是聽覺回饋大大地加速了reafferentation於是將時間的問題最小化，即便沒有完全消除。然而，理論上，此問題的這一面向並非無法克服，只要我們假設接續性的組合是處在全然發生在大腦中的事件之間，如同我們相信默想理論也是如此。假設神經事件A誘發神經事件B，而這兩者都在左半腦的皮質上；現在這些皮質事件之間的傳導時間會是可以忽略的。這個假設在神經科學上是天真的(見第五章)而且也不能克服其它對於組合式模型更基本的異議，亦即解釋所有說話者預測尚未發生事件的能力。
We may illustrate the problem in this way: let us think of a speech act (such as repeating any given word) as an assembly of four distinct processes as shown in Fig. 3.9. In the first process acoustic energy variations are received and analyzed into language-function units called phonemes. The details of this process need not concern us here. In the second process an inventory is made of all the muscle which enter into the production of each speech sound. (These processes are, of course, not “real physiological events” but theoretical stages that help us visualize the complications of speech production.) A more detailed diagram of the second process is shown in Fig. 3.10. Each column represents one speech sound.
我們也許可以用這樣的方式來說明這個問題：讓我們把一個說話的動作(像是重覆任一個給定的詞)想成是四個不同的過程(如圖3.9所示)。在第一個過程當中，聲的差異被接收到而且被分析為語言-功能單位，稱之為音位。在此我們不需要關注這個過程的細節。在第二個過程中，產生了所有參與語音產出的所有肌肉的清單。(當然，這些過程不是”實際上的生理學事件”，而是幫助我們把語言產生的紛雜具像化的理論性階段。)有關第二個過程更詳細的圖表可見於圖3.10。每一欄呈現了一個語音。
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