Which of the following would be considered an abnormal EEG response to photic stimulation?

A photoparoxysmal response is characterized by an abnormal EEG reaction to photic stimulation, indicating an increased susceptibility to seizures or interictal spikes in patients, particularly those with conditions such as epilepsy. This response typically involves the appearance of abnormal discharges in the EEG that can be triggered by light flashes and signifies that the patient may have an underlying predisposition to seizures related to sensory stimuli.

In contrast, a normal photic response results in a pattern of activity that is expected and typical under photic stimulation without signs of abnormality. Photic fade describes a reduction in the amplitude or response to continued light stimulation, which is a common and typically benign phenomenon. Baseline activity refers to the EEG background activity in the absence of stimulation, which would not be affected by photic stimulation and therefore would not be considered a response at all.

Understanding these concepts helps delineate between normal and abnormal EEG responses, particularly in the context of stimulating conditions that may provoke different types of brain activity.