“She [Professor Christine Blasey Ford] can’t tell us how she got home and how she got there,” scorned Senator Lindsey Graham during the lunch break of yesterday’s riveting U. S. Senate Judiciary Committee hearing regarding Ford’s memory of being assaulted by Supreme Court nominee Brett Kavanaugh. Graham’s assumption, widely voiced by fellow skeptics of Ford’s testimony, is that her inability to remember simple peripheral details discounts the authenticity of her assault memory.
But Graham and the other skeptics fail to understand, first, how extreme emotions signal the brain to “save this!” for future reference. (Likely you, too, have enduring “flashbulb memories” for long-ago emotional experiences?) And second, they fail to understand that peripheral details typically fall into oblivion. In Psychology, 12th Edition, Nathan DeWall and I explain:
Our emotions trigger stress hormones that influence memory formation. When we are excited or stressed, these hormones make more glucose energy available to fuel brain activity, signaling the brain that something important is happening. Moreover, stress hormones focus memory. Stress provokes the amygdala (two limbic system, emotion processing clusters) to initiate a memory trace that boosts activity in the brain’s memory-forming areas (Buchanan, 2007; Kensinger, 2007) (FIGURE 8.9). It’s as if the amygdala says, “Brain, encode this moment for future reference!” The result? Emotional arousal can sear certain events into the brain, while disrupting memory for irrelevant events (Brewin et al., 2007; McGaugh, 2015).
Significantly stressful events can form almost unforgettable memories. After a traumatic experience—a school shooting, a house fire, a rape—vivid recollections of the horrific event may intrude again and again. It is as if they were burned in: “Stronger emotional experiences make for stronger, more reliable memories,” noted James McGaugh (1994, 2003). Such experiences even strengthen recall for relevant, immediately preceding events [such as going up the stairway and into the bedroom, in Ford’s case] (Dunsmoor et al., 2015: Jobson & Cheraghi, 2016). This makes adaptive sense: Memory serves to predict the future and to alert us to potential dangers. Emotional events produce tunnel vision memory. They focus our attention and recall on high priority information, and reduce our recall of irrelevant details (Mather & Sutherland, 2012). Whatever rivets our attention gets well recalled, at the expense of the surrounding context.
And as I suggested in last week’s essay, Graham and others seem not to understand “state-dependent memory”—that what people experience in one state (such as when drunk) they may not remember in another state (sober). Nor are Kavanaugh’s supporters recognizing that heavy drinking disrupts memory formation, especially for an experience that would not have been traumatic for him. Thus, Kavanaugh could be sincerely honest in not recalling an assaultive behavior, but also, possibly, sincerely wrong.
(For David Myers’ other weekly essays on psychological science and everyday life visit www.TalkPsych.com.)