There are many relevant brain areas, but I will focus on just two that are known to affect emotional processes. First consider the amygdala, a small almond-shaped area located in the lower middle part of the brain, below the cortex (figure 5.1). Recordings of neuron firings in animals and brain-scanning experiments in humans show the amygdala is important for emotions, especially fear. For example, when people are shown a picture of a scary face, brain scans show an increase of blood flow to the amygdala, indicating that the neurons in it are firing more rapidly and need renourishing. Hence it is plausible that the experience of being afraid of a gruesome face requires an association between the firing of neurons that visually represent the face and the firing of neurons in the amygdala. We may say or think that the face is scary, but this is only a verbal description of the emotional experience of fear of the face. All mammals have an amygdala, and there are analogous regions in fish and reptiles. The amygdala has reciprocal connections with many other brain areas, including the prefrontal cortex, so that neural populations in the amygdala can increase the firing of neurons in the cortex, and vice versa.