  Adversarial algorithms have shown to be effective against neural networks for
a variety of tasks. Some adversarial algorithms perturb all the pixels in the
image minimally for the image classification task in image classification. In
contrast, some algorithms perturb few pixels strongly. However, very little
information is available regarding why these adversarial samples so diverse
from each other exist. Recently, Vargas et al. showed that the existence of
these adversarial samples might be due to conflicting saliency within the
neural network. We test this hypothesis of conflicting saliency by analysing
the Saliency Maps (SM) and Gradient-weighted Class Activation Maps (Grad-CAM)
of original and few different types of adversarial samples. We also analyse how
different adversarial samples distort the attention of the neural network
compared to original samples. We show that in the case of Pixel Attack,
perturbed pixels either calls the network attention to themselves or divert the
attention from them. Simultaneously, the Projected Gradient Descent Attack
perturbs pixels so that intermediate layers inside the neural network lose
attention for the correct class. We also show that both attacks affect the
saliency map and activation maps differently. Thus, shedding light on why some
defences successful against some attacks remain vulnerable against other
attacks. We hope that this analysis will improve understanding of the existence
and the effect of adversarial samples and enable the community to develop more
robust neural networks.
