What happens to a neural impulse if the threshold is not reached?

When a neural impulse occurs, it is dependent on reaching a certain threshold level of stimulation. If this threshold is not reached, the neuron fails to generate an action potential, which means the neural impulse does not occur at all. This is a fundamental concept in neuroscience known as the "all-or-nothing principle." If the stimulus is below the threshold, the neuron remains in a resting state and does not transmit the signal. This means that there is no activation of the neuron to send a message to other neurons or tissues, ensuring that only significant stimuli can trigger a response.

In contrast to other options, the idea that the impulse could travel slowly or lose strength applies only when the threshold is reached but not fully maintained during transmission, which is not the case when the threshold isn't reached at all. Additionally, the concept of the impulse continuing as normal contradicts the essential requirement of threshold achievement for action potential generation. This highlights the critical role of sufficient stimulus intensity in neural communication.