What does 'flat decision-making' mean?

Question

What does flat decision-making mean?

The pure reason process advocated by Plato and Descartes is really more like the strategy patients with cortical prefrontal damage use to make decisions. Several forms of dementia plagued my father before he passed away. He had lost considerable access to his value system. Before advanced dementia, he always chose an O’Henry chocolate bar as a sweet treat. In the latter years, when I took him to a candy counter, he would scan the display for several minutes, reaching, hesitating, and finally choosing. He never chose an O’Henry bar, and the process seemed to take an eternity. I’m sure his final choice was based on giving up and taking the most appealing package within reach. It appeared that he lost the ability to make value-based decisions. When faced with a value-based choice between several competing selections, his decision-making landscape appeared hopelessly flat.

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Answer 1

It isn't the decision-making that is flat, but the landscape. A flat landscape has no hills or valleys, that is, it is featureless. The dementia patient's prospect had no high or low features, no values; finally, he chooses based on the visual appeal of the packages.

Answer 2

It was not his decision-making that was 'flat', but the metaphorical 'landscape' behind it. This isn't a standard expression. I suppose the author means that his father had no memories of his earlier preferences and habits to make the process of choosing interesting to him.