What term describes the size of the summation area used to trigger an action potential?

What term describes the size of the summation area used to trigger an action potential?

• A. Receptive field
• B. Summation field
• C. Effective area
• D. Critical area

Answer: (D)

The size of the region whose stimulation can influence a neuron’s firing is called the receptive field. This area defines the spatial extent over which inputs can be integrated to push the neuron to fire an action potential. In sensory systems, the receptive field sets how large an area must be stimulated to affect the firing rate, and in many pathways it can have a center-surround structure that shapes responses depending on where within the field the stimulus occurs. The other terms aren’t standard descriptors for this trigger area—there isn’t a widely used concept called a “summation field,” and “effective area” or “critical area” don’t capture the neural boundary that determines when an action potential is reached.

The size of the region whose stimulation can influence a neuron’s firing is called the receptive field. This area defines the spatial extent over which inputs can be integrated to push the neuron to fire an action potential. In sensory systems, the receptive field sets how large an area must be stimulated to affect the firing rate, and in many pathways it can have a center-surround structure that shapes responses depending on where within the field the stimulus occurs. The other terms aren’t standard descriptors for this trigger area—there isn’t a widely used concept called a “summation field,” and “effective area” or “critical area” don’t capture the neural boundary that determines when an action potential is reached.