Can animals remember things the way people do? Yes, says cognitive psychologist Howard Eichenbaum, PhD, who directs the Center for Memory and Brain at Boston University. He will discuss 25 years of studies leading to this discovery at this year's Master Lecture at APA's Annual Convention in Toronto, Aug. 6–9.
"Even animals as lowly as rats have features of memory that we call recollection in humans," says Eichenbaum.
In particular, they can remember items in context rather than just being familiar with them, the capacity known as episodic memory.
Eichenbaum will discuss the cognitive psychology and neuroscience methods he used to uncover this ability. For instance, his studies have taken two related methods—recognition memory tasks and signal detection analysis, which together allow researchers to determine whether a person is using episodic memory, familiarity or both—and used cues and stimuli that are relevant to rats, such as odors and food rewards.
"If you give animals ways of expressing themselves that are natural to their behavioral repertoire, they'll tell you exactly what they know," he says.
He also has staked out new territory by employing neuroscience methods that would be impossible to use in humans. For instance, he's found that removing rats' hippocampi wipes out the animals' capacity for episodic memory, but not their familiarity with objects. And by attaching tiny electrodes to hippocampal neurons, he has shown that these neurons fire in relation to specific items and their contexts, lending new specificity to the role of the hippocampus in episodic memory.
Eichenbaum also will share studies that point to how episodic memory operates in the rat brain, adding new physiological data to a growing body of literature suggesting that the hippocampus serves as a central meeting point for memory-based information.
Marrying cognitive psychology and neuroscience is what helped him elucidate these findings, he notes.
"The right answer to many of the questions about how the mind works really requires a high level of sophistication in both disciplines," he says.
Tori DeAngelis is a writer in Syracuse, N.Y.
Eichenbaum's lecture is at 1 p.m. on Aug. 7.