After the magic of brain encoding and storage, we still have the daunting task of retrieving the information. What triggers retrieval?

25-6 How do external cues, internal emotions, and order of appearance influence memory retrieval?

Imagine a spider suspended in the middle of her web, held up by the many strands extending outward from her in all directions to different points. If you were to trace a pathway to the spider, you would first need to create a path from one of these anchor points and then follow the strand down into the web.

The process of retrieving a memory follows a similar principle, because memories are held in storage by a web of associations, each piece of information interconnected with others. When you encode into memory a target piece of information, such as the name of the person sitting next to you in class, you associate with it other bits of information about your surroundings, mood, seating position, and so on. These bits can serve as retrieval cues that you can later use to access the information. The more retrieval cues you have, the better your chances of finding a route to the suspended memory.

The best retrieval cues come from associations we form at the time we encode a memory—smells, tastes, and sights that can evoke our memory of the associated person or event. To call up visual cues when trying to recall something, we may mentally place ourselves in the original context. After losing his sight, British scholar John Hull (1990, p. 174) described his difficulty recalling such details:

I knew I had been somewhere, and had done particular things with certain people, but where? I could not put the conversations … into a context. There was no background, no features against which to identify the place. Normally, the memories of people you have spoken to during the day are stored in frames which include the background.

PrimingOften our associations are activated without our awareness. Philosopher-psychologist William James referred to this process, which we call priming, as the “wakening of associations.” Seeing or hearing the word rabbit primes associations with hare, even though we may not recall having seen or heard rabbit (FIGURE 25.5).

Priming is often “memoryless memory”—invisible memory, without your conscious awareness. If, walking down a hallway, you see a poster of a missing child, you will then unconsciously be primed to interpret an ambiguous adult-child interaction as a possible kidnapping (James, 1986). Although you no longer have the poster in mind, it predisposes your interpretation. Meeting someone who reminds us of a person we’ve previously met can awaken our associated feelings about that earlier person, which may transfer into the new context (Andersen & Saribay, 2005; Lewicki, 1985).

Priming can influence behaviors as well (Herring et al., 2013). In one study, participants primed with money-related words were less likely to help another person when asked (Vohs et al., 2006). In another, people primed with money words or images expressed more support for free-market capitalism and social inequality (Caruso et al., 2013). In such cases, money may prime our materialism and self-interest rather than the social norms that encourage us to help (Ariely, 2009).

Context-Dependent MemoryHave you noticed? Putting yourself back in the context where you experienced something, such as in a childhood home or neighborhood, can prime your memory retrieval. As FIGURE 25.6 illustrates, when scuba divers listened to a word list in two different settings (either 10 feet underwater or sitting on the beach), they recalled more words if retested in the same place (Godden & Baddeley, 1975).

By contrast, experiencing something outside the usual setting can be confusing. Have you ever run into your doctor in an unusual place, such as at the store or park? You knew the person but struggled to figure out who it was and how you were acquainted? The encoding specificity principle helps us understand how cues specific to an event or person will most effectively trigger that memory. In new settings, you may not have the memory cues needed for speedy face recognition. Our memories depend on context, and on the cues we have associated with that context.

In several experiments, Carolyn Rovee-Collier (1993) found that a familiar context could activate memories even in 3-month-olds. After infants learned that kicking would make a crib mobile move via a connecting ribbon from the ankle, the infants kicked more when tested again in the same crib than when in a different context.

State-Dependent MemoryClosely related to context-dependent memory is state-dependent memory. What we learn in one state—be it drunk or sober—may be more easily recalled when we are again in that state. What people learn when drunk they don’t recall well in any state (alcohol disrupts storage). But they recall it slightly better when again drunk. Someone who hides money when drunk may forget the location until drunk again.

Our mood states provide an example of memory’s state dependence. Emotions that accompany good or bad events become retrieval cues (Fiedler et al., 2001). Thus, our memories are somewhat mood congruent. If you’ve had a bad evening—your date never showed, your Toledo Mud Hens hat disappeared, your TV went out 10 minutes before the end of a show—your gloomy mood may facilitate recalling other bad times. Being depressed sours memories by priming negative associations, which we then use to explain our current mood. In many experiments, people put in a buoyant mood—whether under hypnosis or just by the day’s events (a World Cup soccer victory for German participants in one study)—have recalled the world through rose-colored glasses (DeSteno et al., 2000; Forgas et al., 1984; Schwarz et al., 1987). They judged themselves competent and effective, other people benevolent, happy events more likely.

Knowing this mood-memory connection, we should not be surprised that in some studies currently depressed people have recalled their parents as rejecting, punitive, and guilt promoting, whereas formerly depressed people’s recollections more closely resembled the more positive descriptions given by those who never suffered depression (Lewinsohn & Rosenbaum, 1987; Lewis, 1992). Similarly, adolescents’ ratings of parental warmth in one week gave little clue to how they would rate their parents six weeks later (Bornstein et al., 1991). When teens were down, their parents seemed inhuman; as their mood brightened, their parents morphed from devils into angels. We may nod our heads knowingly. Yet, in a good or bad mood, we persist in attributing to reality our own changing judgments, memories, and interpretations. In a bad mood, we may read someone’s look as a glare and feel even worse. In a good mood, we may encode the same look as interest and feel even better. Passions exaggerate.

Mood effects on retrieval help explain why our moods persist. When happy, we recall happy events and therefore see the world as a happy place, which helps prolong our good mood. When depressed, we recall sad events, which darkens our interpretations of current events. For those of us with a predisposition to depression, this process can help maintain a vicious, dark cycle.

Serial Position EffectAnother memory-retrieval quirk, the serial position effect, explains why we may have large holes in our memory of a list of recent events. Imagine it’s your first day in a new job, and your manager is introducing co-workers. As you meet each person, you silently repeat everyone’s name, starting from the beginning. As the last person smiles and turns away, you feel confident you’ll be able to greet your new co-workers by name the next day.

Don’t count on it. Because you have spent more time rehearsing the earlier names than the later ones, those are the names you’ll probably recall more easily the next day. In experiments, when people viewed a list of items (words, names, dates, even odors) and immediately tried to recall them in any order, they fell prey to the serial position effect (Reed, 2000). They briefly recalled the last items especially quickly and well (a recency effect), perhaps because those last items were still in working memory. But after a delay, when their attention was elsewhere, their recall was best for the first items (a primacy effect; see FIGURE 25.7).