Science of motivation

Dan Pink examines the puzzle of motivation, starting with a fact that social scientists know but most managers don't: Traditional rewards aren't always as effective as we think. Listen for illuminating stories -- and maybe, a way forward.

The Episodic-inhibition hypothesis

Consolidation of Episodic Memories During Sleep: Long-Term Effects of Retrieval Practice
Psychological Science OnlineFirst, published on November 23, 2009 as doi:10.1177/0956797609354074
Mihály Racsmány, Martin A. Conway, and Gyula Demeter

Two experiments investigated the long-term effects of retrieval practice. In the retrieval-practice procedure, selected items from a previously studied list are repeatedly recalled. The typical retrieval-practice effects are considerably enhanced memory for practiced items accompanied by low levels of recall, relative to baseline, for previously studied items that are associated with the practiced items but were not themselves practiced. The two experiments demonstrated that the former effect persisted over 12 hr; the latter effect also persisted over 12 hr, but only if a period of nocturnal sleep occurred during the retention interval. We propose that consolidation processes occurring during sleep, and possibly featuring some form of offline rehearsal, mediate these long-term effects of retrieval practice.

More faithful memories for those experiences

Awake replay of remote experiences in the hippocampus
Nature Neuroscience Volume 12, Number 7, July 2009
Published online at http://www.nature.com/natureneuroscience
Mattias P Karlsson & Loren M Frank

Hippocampal replay is thought to be essential for the consolidation of event memories in hippocampal-neocortical networks. Replay is present during both sleep and waking behavior, but although sleep replay involves the reactivation of stored representations in the absence of specific sensory inputs, awake replay is thought to depend on sensory input from the current environment. Here, we show that stored representations are reactivated during both waking and sleep replay. We found frequent awake replay of sequences of rat hippocampal place cells from a previous experience. This spatially remote replay was as common as local replay of the current environment and was more robust when the rat had recently been in motion than during extended periods of quiescence. Our results indicate that the hippocampus consistently replays past experiences during brief pauses in waking behavior, suggesting a role for waking replay in memory consolidation and retrieval.

Growing Older Does Not Mean Sleeping Poorly

Recent Advances in Understanding Sleep and Sleep Disturbances in Older Adults
Growing Older Does Not Mean Sleeping Poorly
Association for Psychological Science Volume 18—Number 6
Michael V. Vitiello

Despite commonly held assumptions, growing older does not necessarily result in disturbed or unsatisfying sleep. There is no reason to assume, a priori, that the sleep of an older adult is necessarily problematic; in fact, many high-functioning older adults are satisfied with their sleep. When the various factors that can disrupt sleep— poor health, primary sleep disorders, poor sleep-hygiene practices (e.g., irregular sleep schedules and poor sleeping environments), and so on—are screened out, ‘‘optimally’’ or ‘‘successfully’’ aging older adults, assuming they remain healthy, can expect to experience little further change in their sleep and are not likely to experience excessive daytime sleepiness and the concomitant need to nap regularly during the day. Nevertheless, the majority of older adults, who are not optimally aging, suffer significant sleep disturbances from a variety of causes. Fortunately, our growing understanding of how sleep changes with aging and of the causes of these changes is informing ever-improving treatments for these disturbances, thereby helping to ensure that growing older does not mean sleeping poorly.

A theory of protoconsciousness

REM sleep and dreaming: towards a theory of protoconsciousness
Nature Reviews| Neuroscience volume 10 | November 2009 | 803
J. Allan Hobson

Dreaming has fascinated and mystified humankind for ages: the bizarre and evanescent qualities of dreams have invited boundless speculation about their origin, meaning and purpose. For most of the twentieth century, scientific dream theories were mainly psychological. Since the discovery of rapid eye movement (REM) sleep, the neural underpinnings of dreaming have become increasingly well understood, and it is now possible to complement the details of these brain mechanisms with a theory of consciousness that is derived from the study of dreaming. The theory advanced here emphasizes data that suggest that REM sleep may constitute a protoconscious state, providing a virtual reality model of the world that is of functional use to the development and maintenance of waking consciousness.

True or False?

How to Tell If a Particular Memory Is True or False
Daniel M. Bernstein and Elizabeth F. Loftus
Association for Psychological Science Volume 4—Number 4

How can you tell if a particular memory belonging to you or someone else is true or false? Cognitive scientists use a variety of techniques to measure groups of memories, whereas police, lawyers, and other researchers use procedures to determine whether an individual can be believed or not. We discuss evidence from behavioral and neuroimaging studies and research on lying that have attempted to distinguish true from false memories.

We remember events, people, and places all the time, but how accurate are those memories? More specifically, how can we identify true memories from false ones? A majority of studies trying to answer this question have tended to focus on one of several possible methods of analysis, concentrating on either groups of memories being reported (e.g., studying word lists and then remembering related words that were not included in the original lists) or the person who is reporting the memories (for example, using a battery of self-report questionnaires and behavioral assessments to predict who may be susceptible to forming false memories). In a new report, Daniel M. Bernstein and Elizabeth F. Loftus suggest that a combined approach — focusing on groups of memories, on the person who is remembering, and on the individual memory — along with taking advantage of a variety of research tools available (such as imaging devices, mathematical models, analysis techniques, and statistical methods) may be the best way to determine if a memory is truth or fiction.

Join the discussion here on APS.

Transform Your Mind, Change Your Brain

In this talk, Richard J. Davidson explores recent scientific research on the neuroscience of positive human qualities and how they can be cultivated through contemplative practice. Distinctions among different forms of contemplative practices are introduced and shown to have different neural and behavioral consequences, as well as important consequences for physical health in both long-term and novice practitioners. New research also shows that meditation-based interventions delivered online can produce behavioral and neural changes. Collectively, this body of research indicates that we can cultivate adaptive neural changes and strengthen positive human qualities through systematic mental practice.