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Priming 1055

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Priming

R Henson, MRC Cognition and Brain Sciences Unit,Cambridge, UK

ã 2009 Elsevier Ltd. All rights reserved.

Introduction

Priming refers to a change in behavioral response to astimulus, following prior exposure to the same, or arelated, stimulus. Examples include faster reactiontimes to make a decision about the stimulus, a biasto produce that stimulus when generating responses,or the more accurate identification of a degradedversion of the stimulus. From the memory perspec-tive, the most exciting aspect to priming concernsevidence that it can occur in the absence of consciousmemory for the prior exposure (an example of so-called ‘implicit’ or ‘nondeclarative’ memory). For in-stance, amnesic patients typically show intact levelsof priming, despite their impairments in conscious(‘explicit’ or ‘declarative’) memory. Evidence likethis led to the proposal that the brain regions support-ing priming are different from the medial temporallobe (MTL) regions believed to support declarativememory. Indeed, it is often assumed that priming isthe by-product of prior processing of a stimulus, thatis, arising from plasticity in multiple cortical regionswhose primary role is perceptual/conceptual proces-sing. As such, priming is likely to be one of the mostbasic expressions of memory, influencing how weperceive and interpret the world.

A Working Example

Priming can be measured using a range of differentstimuli and tasks. To illustrate the breadth of neuro-scientific data on priming, we initially focus on onespecific paradigm – the word-stem completionparadigm – which has provided some of the mostconvincing evidence that priming involves memorysystems, and associated brain regions, that differfrom those involved in declarative memory. In the‘study’ phase of this paradigm, participants performan incidental task on a list of words (normally un-aware that their memory for these words will betested). At some time later, they are presented withthree letters that form the start of words (word-stems)(see Figure 1(a)). Some of these stems can be com-pleted with the words from the study phase, though inthe ‘indirect’ version of this task, participants are notinformed of any relationship between this test phaseand the previous study phase. They are simply asked

Encyclopedia of Neuroscienc

to complete the stem with the first word that comes tomind. Priming is indexed by the increased probabilityof completing stems with studied words, relative tothe baseline probability of completing the stems whenthose words were not studied. Importantly, partici-pants normally show this priming without reportingany conscious reference to the prior study phase.

Neuropsychological Evidence

When this task is given to amnesic patients, theytypically show priming of equivalent magnitude tocontrols. However, when the instructions at test arechanged, so that participants are asked to use thestems explicitly to recall studied words (‘word-stemcued recall,’ a ‘direct’ version of the task), amnesicpatients typically perform worse than controls(Figure 1(b)). This dissociation is appealing becausethe stimuli are kept constant across the indirect anddirect versions of the task; all that differs are theinstructions. While amnesic patients are also knownto have sparing of other forms of memory, such asmotor skill-learning, the intriguing aspect of primingis that it can occur after a single stimulus presentation(‘one-shot learning’), rather than requiring sustainedtraining. Furthermore, a few patients with more pos-terior lesions (e.g., in occipital cortex) have shown thereverse pattern of impaired word-stem completion forvisually studied words (indirect test), despite intactperformance on a recognition memory test (directtest). This double dissociation between the twotypes of memory test is strong support for differentmemory systems underlying priming and declarativememory. Further support comes from reports thatword-stem completion priming is less susceptiblethan is cued recall to the effects of healthy aging,and to some dementias like Alzheimer’s disease.

Psychological Evidence

This dissociation of priming from declarative memoryfollowing brain damage is supported by functionaldissociations between direct and indirect versions ofthe word-stem completion paradigm in healthy indi-viduals. For example, performance on the directversion (word-stem cued-recall) is higher when thecorresponding words are generated from semanticcues at study relative to when they are simply read,yet performance on the indirect version (word-stemcompletion) is higher when the words are read relativeto being generated from cues. Similarly, presentingwords auditorily rather than visually at study tendsto impair performance on visual word-stem comple-tion to a greater extent than on visual word-stem cued

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Figure 1 (a) Schematic of the word-stem completion paradigm. (b) Performance of amnesic patients and matched controls on indirect

(completion) and direct (cued-recall) versions of the task. (b) Reprinted with permission from Graf P, Squire LR, and Mandler G (1984) The

information that amnesic patients do not forget. Journal of Experimental Psychology: Learning,Memory and Cognition 10: 164–178, APA

publishers.

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recall, whereas use of a study task that engages seman-tic versus phonological processing of words tends toimprove performance on word-stem cued recall to agreater extent than on word-stem completion. Thereduced performance found on word-stem completionwhen words are generated or heard at study, ratherthan read, suggests that a component of priming in thistask relates to the visual overlap between words andtheir stems, or more precisely, to overlap in the pro-cesses involved in visual word reading.Nonetheless, though dissociations have been found

between direct and indirect tests of memory, care mustbe taken when using performance on indirect tests as apure measure of implicit memory: even though anindirect memory test does not refer participants toprevious encounters with stimuli, participants mayvoluntarily, or involuntarily, recollect such encounters.For example, some participantsmay guess the relation-ship between the study and test phase of a word-stemcompletion task, and hence attempt to recall studieditems in order to complete the stems.Moreover, even ifa completion comes tomind involuntarily, participantsmay subsequently recognize that word as having comefrom the study phase. Though the latter eventualitymay not affect behavioral measures of priming, it isimportant when measuring the neural correlates ofpriming, as discussed in the next two sections. As aconsequence, considerable effort has been devoted todeveloping methods that minimize the contribution ofexplicit memory to priming.

Neuroimaging Evidence

Some of the first positron emission tomography (PET)and functional magnetic resonance imaging (fMRI)studies of priming used the word-stem completion

Encyclopedia of Neuroscience

paradigm. These studies consistently found reducedhemodynamic responses in extrastriate visual cortexfor studied relative to unstudied word-stems (often inboth direct and indirect versions of the task). Thisreduction is attributed to ‘more efficient’ or ‘facili-tated’ visual processing of the stems corresponding tostudied words, owing to the prior exposure to thosewords. Similar reductions have also been found in anumber of regions including left inferior temporal andleft inferior frontal cortices. Given that these regionsare also generally activated by the task (e.g., vs. passivefixation), the reductions are consistent with facilitatedprocessing within a language-related network that isengaged when reading words and completing word-stems, possibly including phonological, lexical, andsemantic processes.

Some imaging studies have also reported hemo-dynamic increases in MTL cortices, even in indirectversions of the task. This illustrates the problem high-lighted earlier that explicit memory may contaminateindirect tasks. In particular, even if this explicit mem-ory is involuntary and does not affect the behavioralresponse, the poor temporal resolution of hemo-dynamic imaging techniques means that imaging datamay include explicit memory processes arising sub-sequent to that response.More recent imaging experi-ments have therefore used variants of the word-stemcompletion paradigm that attempt to minimize con-tamination by explicit memory. For example, partici-pants can be asked to complete stems with wordsfrom the study phase (i.e., word-stem cued recall),but if they cannot, they are asked to produce thefirst word coming to mind. Having produced a com-pletion (through either approach), they then indicatewhether they remember that word from the study

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phase. The critical trials used to isolate the neuralcorrelates of priming are those stems completedwith studied words but which participants indicatedthey did not remember. These trials are likely toprovide a purer measure of implicit memory (despiteoccurring in the context of a direct memory task).When compared to a baseline condition (stems thatdid not correspond to studied words, but whichwere completed with a word that was correctly indi-cated as unstudied), event-related fMRI has repli-cated the reduced responses found in extrastriate,left inferior temporal, and left inferior frontal cortices(Figure 2(a)). Equivalent reductions in these regionswere also found for ‘remembered’ trials (stems that

Occipital

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Figure 2 Event-related fMRI data from a word-stem completion par

shown in left inferior frontal, left inferior temporal and occipital cortice

remembered stems (reds), relative to baseline stems (greens), regard

indirect (darker colors) version of the paradigm. In the study phase (b

and inferior temporal cortices showed reduced responses for subsequ

whereas regions in medial temporal lobe showed increased respons

relative to subsequently forgotten words (lighter bar). Rem, remembere

with permission from Schott BH, Henson RN, Richardson-Klavehn A, e

neuroanatomy of priming, remembering and control of retrieval. Proc

America 102: 1257–1262. (b) Adapted with permission from Schott B,

dissociation of encoding processes related to priming and explicit m

National Academy of Sciences, USA.


were completed with a studied word and that wordwas indicated as studied), unlike in MTL cortex,where greater activity was found for rememberedtrials relative to primed trials (suggesting that explicitmemory had been successfully minimized in primedtrials). Furthermore, the reductions for primed andremembered versus baseline trials in these regionswere also found when using an indirect version ofthe task akin to the standard word-stem completiontask. Taken together, these results suggest that suchhemodynamic reductions are not only implicit, butalso automatic, consistent with a role for theseregions in the priming observed in healthy individualsand in amnesic patients.

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adigm. In the test phase (a), a number of regions including those

s, exhibited reduced responses to primed stems (blues), and to

less of whether participants performed a direct (lighter colors) or

), a number of regions including those shown in left inferior frontal

ently primed relative to subsequently forgotten words (darker bar),

es for subsequently remembered (but not subsequently primed)

d; Pri, primed; Bas, baseline; For, forgotten (see text). (a) Adapted

t al. (2005) Redefining implicit and explicit memory: The functional

eedings of the National Academy of Sciences of United States of

Richardson-Klavehn A, Henson R, et al. (2006) Neuroanatomical

emory. Journal of Neuroscience 26: 792–800. Copyright (2005)

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1058 Priming


One can also use event-related imaging methods toexamine differences at the time stimuli are encoded(i.e., during the study phase) as a function of the degreeto which those stimuli show later priming (or thedegree to which they show explicit memory). Usingthe same paradigm as above, for example, hemo-dynamic responses to the words at study differed forthose words subsequently primed (completed withthe studied word but not remembered) than thosesubsequently forgotten (completed with a differentword). Such differences were found in a number ofcortical regions, including the left inferior temporaland frontal regions that showed priming-related reduc-tions at test. Again, the pattern in these regions differedfrom that in the MTL, which showed greater activityfor words subsequently remembered versus words sub-sequently forgotten (Figure 2(b)). These findings sug-gest that priming is affected by how stimuli areencoded (on their initial presentation), possibly in

Priming−priming baseline

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Figure 3 Electrophysiological data from a word-stem completion

parietotemporal electrodes recorded by EEG diverge between prim

baseline stems (lower plot), within 200ms, whereas the ERPs to prim

phies also differ). In the upper panel of (b), regions with reliable differen

data, for repeated versus novel presentation of stems are shown for tw

are shown for a number of regions of interest. (a) Data adapted with pe

cortical activations in implicit and explicit recall. Journal of Neuroscien

RP, Buckner RL, Dale AL, Marinkovic K, and Halgren E (2001) Spatiote

modification during repetition priming. Journal of Neuroscience 10: 35


addition to how that information is accessed at test.Yet further work has combined event-related fMRIwith pharmacological interventions: for example,scopolamine and lorezapam, which are believed tomodulate synaptic plasticity, have been shown to atten-uate repetition suppression in the same inferior tempo-ral and frontal regions during word-stem completion.

Electrophysiological Evidence

The time course of word-stem completion priminghas also been investigating using electroencephalo-graphic (EEG) and magnetoencephalographic (MEG)methods. For example, in a standard indirect com-pletion task, event-related potentials (ERPs) to primedword-stems have been reported to diverge from thoseto baseline (unstudied) word-stems within 200msof the onset of the word-stem (Figure 3(a)). The sameERP effect was reported for words remembered during

al gyrus Posterior planum temporaleNovel

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paradigm. In (a), the event-related potentials (ERPs) over right

ed and baseline stems (upper plot), and between recalled and

ed and recalled stems only differ from 300ms onwards (topogra-

tial source-reconstructed event-related activity, inferred fromMEG

o time windows. In the lower panel, the reconstructed responses

rmission from Badgaiyan RD and Posner MI (1997) Time-course of

ce 17: 4904–4913. (b) Data adapted with permission from Dhond

mporal maps of brain activity underlying word generation and their

64–3571.

(2009), vol. 7, pp. 1055-1063

Priming 1059


a direct cued-recall version of the task. However,when contrasting primed and remembered word-stems directly, differences only emerged after approxi-mately 300ms. These data suggest that priming occursprior to explicit memory retrieval. Furthermore, andconsistent with fMRI data described above, qualitativedifferences have been found in the study betweenthe differential ERPs to words subsequently primedversus those subsequently remembered. More recently,related experiments (in whichword-stemswere repeat-edly completed) have used the superior spatial resolu-tion of MEG (combined with structural informationfrom MRI) in an attempt to localize the evolution ofrepetition-related effects over the first few hundredmilliseconds from stem onset. Interestingly, an initialrepetition-related increase in electrical activity has beenreported early in left inferior temporal cortex (lateraloccipitotemporal sulcus), followed by a later decreasein both this region and left inferior frontal cortex(Figure 3(b)). Such spatiotemporal data suggestrapid interactions between brain regions, whichwould be invisible to hemodynamic techniques likefMRI. Indeed, such data afford greater opportunityto look at priming-related changes in the connectivi-ty between different brain regions, for example, as afunction of plasticity following initial processing ofstimuli.

Summary

The above studies using the word-stem completionparadigm provide convergent evidence that primingreflects a form of memory dissociable from consciousmemory, and can arise from a number of corticalregions outside the MTL. These regions are normallya subset of those engaged by the specific stimuli andtask (in the above cases, a number of left inferiorfrontal, left inferior temporal, and occipital regionsassociated with word reading), suggesting thatpriming reflects a form of plasticity in these regions.The expression of priming is generally associatedwith reduced neural activity in these regions, possiblyreflecting faster and/or more efficient processing (e.g.,a ‘greasing of the tracks’). This expression appears tooccur very rapidly (around 200ms) and automatical-ly (regardless of precise task). Differences in neuralactivity have also been found during the initial pro-cessing of stimuli as a function of whether they aresubsequently primed. This implicates important rolesfor factors such as attention and the type of proces-sing in the nature of neural/synaptic changes assumedto underlie priming.Similar conclusions have been reached using a

number of other priming paradigms, though thespecific network of cortical regions involved may


differ. Indeed, the general finding of decreased hemo-dynamic responses to repeated stimuli (which hasbeen called ‘repetition suppression’) has beenobserved repeatedly across a range of stimuli andindirect memory tasks. Interestingly, however, notall regions activated by initial presentations of stimulishow such decreases: early sensory regions, such asV1, for example, do not normally show repetitionsuppression. One possibility is that not all of theprocessing stages in a given task show stimulus-specific effects of prior processing (or alternatively,such effects of prior processing have lifetimes shorterthan is typically tested). An interesting theoretical ques-tion is therefore which stages (and associated brainregions) show the largest effects of prior processing?Are they, for example, stages that involve greatest com-petition between alternative outputs/interpretations?

Other Common Measures of Priming

Another commonmeasure of priming is the latency toidentify (e.g., name) pictures of objects. This measurehas shown priming effects that last up to a year. In acommon neuropsychological version, in which de-graded pictures are gradually clarified (the ‘Gollinfigures’), amnesic patients show strong priming (i.e.,earlier identification for pictures identified pre-viously). Researchers have also used such priming toinvestigate the representation of visual objects in thebrain, by examining the extent to which priming-related effects (e.g., in different brain regions) gener-alize across different views of an object.

Another common type of priming is semanticpriming, where the response to a probe word (e.g.,HEAVEN) is speeded when preceded by a relatedprime word (e.g., HELL) relative to a nonrelatedword (e.g., HILL). Such priming tends to be short-lived, often not surviving more than a second betweenthe prime and probe. As with visual object priming, ithas also been used as a tool, in this case to investigatethe organization of semantic memory. Yet anothertype of priming that has been influential on a theoret-ical level is associative priming, where the priming ofa probe stimulus is modulated by whether or not ithas previously been paired with a context stimulus.According to theories that hypothesize a key role forMTL in forming associations, patients with MTLdamage should not show such priming, even if suchpriming is shown to be implicit. At the moment, thedata appear mixed.

There is also much interest in subliminal priming,in which the prime is presented so briefly (around50ms; often forward and backward masked) that par-ticipants show little to no awareness of the prime, andyet still show behavioral priming to a probe stimulus

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presented shortly afterwards (typically within a fewhundred milliseconds). Indeed, this type of priminghas been recommended for imaging studies of implicitprocessing, since it is easier to rule out contaminationby explicit memory for the prime.

Theories of Priming

A broad distinction has been made between ‘percep-tual’ and ‘conceptual’ priming. The main difference isthat perceptual, but not conceptual, priming is affect-ed by differences in the physical features of the primeand probe stimuli, whereas conceptual, but not per-ceptual, priming is affected by differences in thedegree of semantic processing of the stimuli. Thisdistinction is supported by dissociations in, for exam-ple, Alzheimer’s patients, who reportedly show intactperceptual priming but impaired conceptual priming,presumably because the early sensory areas believedto be important for perceptual priming are less affect-ed by the disease than anterior temporal regionsbelieved to be important for conceptual priming.A related distinction assumes that priming is sup-ported by specialized ‘perceptual representationsystems’ that are distinct from the MTL memorysystem. In principle, this allows for dissociable formsof perceptual priming as a function of modality (e.g.,visual vs. auditory).Though useful heuristics, such broad distinctions

do not seem sufficient for the varieties of priming thathave been investigated. For example, the word-stemcompletion task discussed above is difficult to fit intothe perceptual/conceptual dichotomy, since it is af-fected by variations in some physical properties, yetresidual priming can still occur across modalities(even when voluntary explicit retrieval has been ex-cluded). Furthermore, word-stem completion can beunaffected by the degree of semantic processing ofprimes (e.g., semantic vs. phonological), yet be re-duced following very superficial (e.g., graphemic)processing of primes. These data are consistent witha contribution from a lexical component, in additionto perceptual components. Furthermore, other dim-ensions along which indirect tasks differ can alsoproduce behavioral dissociations, such as the distinc-tion between competitive and noncompetitive accessto conceptual information, for example.An alternative perspective is the ‘component pro-

cess’ view of priming, according to which there aretypically several processes involved in a given taskthat may be facilitated by prior processing. As withthe related concept of ‘transfer-appropriate proces-sing,’ the amount of priming will depend on thedegree of overlap between the processes performedon the prime and those performed on the probe


(Figures 4(a) and 4(b)). These processes may derivefrom interactions between brain regions that becomeconfigured according to the task demands. Therefore,‘‘performance will depend on the interplay of compo-nents and the processes they mediate’’ (Moscovitch,1994: 301). A behavioral measure like reaction timeis likely to reflect the conglomeration of the timestaken to perform each component process. Only byvarying the stimuli and task can the key components inbehavioral priming be isolated (Figures 4(b) and 4(c)).Alternatively, the concurrent acquisition of hemo-dynamic or electrophysiological data allows theopportunity to examine activity within the ‘network’of brain regions (and the interactivity between thoseregions) that are configured for the current task.

Another important theoretical dimension is that be-tween ‘structural’ and ‘episodic’ theories of priming.According to structural (or ‘abstractionist’) theories,priming reflects some modification, such as loweredthresholds of, or residual activity in preexisting repre-sentations. According to episodic (or ‘instance’)theories, any exposure to a stimulus can, in principle,leave some residual trace of its processing. Attempts totest these theories have used priming of novel stimuli(e.g., nonwords, or impossible objects) or examinedthe effects of context (e.g., novel associations) onpriming. In general, this distinction is hard to evaluatein the absence of more detailed theories of the natureof representation in the brain (e.g., even nonwords canconsist of familiar bigrams of letters). Nonetheless, oneimportant class of episodic theories assumes that eachstimulus and response within a task can become asso-ciated together, or bound into a single representation(or ‘event record’). In such cases, repetition of thestimulus can directly cue retrieval of the associatedresponse. Such stimulus–response associations havebeen shown to influence behavior, particularly in thecase of subliminal (masked) priming, but also inthe case of ‘negative priming,’ when the response to aprobe stimulus is hindered if the same stimulus haspreviously been presented in the context of a differentresponse (even if an implicit response). Such associa-tions have also been shown to have dramatic effects onimaging data. Though stimulus–response associationscan be minimized by ensuring that the response madeto the probe is unrelated to the response made to theprime, it is clear that when present, such associationscan have important consequences, possibly ‘by-pass-ing’ several stages of processing that occurred on theprime (Figure 4(d)).

Future

One important future direction that provides strongevidence for the direct involvement of circumscribed

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Early visual(Striate)

Visual object(Fusiform?)

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Figure 4 Schematic of the component process view of priming. (a) Initial presentation of an object in a semantic classification task

(living vs. nonliving) involves interactions between a number of processing stages between the stimulus (left) and response (right).

Putative brain regions associated with each stage are shown. (b) Repetition of the same object in the same task causes faster

classification by virtue of facilitated processing in some (but not necessarily all) of the stages (facilitation indicated by darker lines).

(c) A change in the stimulus involves re-processing in only one of the original stages (in this example), leading to reduced priming (and

potential isolation of semantic component). (d) The formation of direct a stimulus–response association (event record) can also cause

priming, even though it bypasses the initial processing stages. Inf, inferior; Front, frontal cortex; Temp, temporal.

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brain regions in priming is the use of transcranialmagnetic stimulation (TMS). In the only such studyto date, either left inferior frontal cortex or a controlsite was stimulated approximately 300ms after theinitial presentation of a visual object. Frontal stimu-lation reduced the amount of priming for semanticclassification of that object when it was repeated later(Figure 5(a)). Moreover, repetition suppression forthat object, when later repeated, was abolished inleft inferior frontal cortex, but not in occipital cortex(Figure 5(b)). This supports the existence of at leasttwo components to priming in this task: for example,a visual component in occipital cortex and a verbalcomponent in left inferior frontal cortex.Another important future direction is the combina-

tion of multiple imaging modalities, such as the com-bination of spatial information in fMRI with thetemporal information in MEG. Once the detailedtime course of activity can be estimated in differentbrain regions, one can go further and explore changesin the covariance between these time courses, in orderto infer directionality and possible causality. It willalso be useful to acquire more fMRI and EEG/MEGdata on amnesic patients, to confirm that priming-related changes in brain activity persist despite com-promised activity in MTL.


From a theoretical perspective, more detailed mod-els of the causes of priming are needed. According tothe ‘component process view’ mentioned above, animportant question is: What is the nature of processesthat lead to facilitation when they are re-engaged, in astimulus-specific manner, in relation to other process-es that may not show such facilitation? And how doesthis component process view incorporate other evi-dence suggesting a role for direct stimulus–responseassociations, or episodic records? Some computation-al models have been used to fit behavioral priming;such models now need to be extended to the neurallevel, to make contact with the imaging and electro-physiological data described above. One importantquestion for these models is: Is there a single neuralmechanism underlying priming, or multiple mecha-nisms operating on different spatial and temporalscales (e.g., long-term potentiation/depression, orsynaptic depression, or even firing-rate adaptation)?

A final important question is how priming andexplicit memory, if truly dissociable, nonetheless in-teract in many circumstances. Some have suggestedthat the cause of priming (often described as increased‘fluency’ of processing) can, under some conditions,be utilized by people in order to make an explicitmemory judgment. In other words, people can

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Figure 5 A transcranial magnetic stimulation (TMS) study of priming. (a) Using a semantic classification task like in Figure 4, TMS of

left inferior frontal cortex (but not of a control region in left motor cortex) shortly after initial presentation of visual objects reduced

subsequent behavioral priming. (b) TMS of the frontal region abolished fMRI repetition suppression in that region when the object was

subsequently repeated but did not abolish repetition suppression in occipital cortex. LIFG, left inferior frontal gyrus; MOG, middle occipital

gyrus. Adapted by permission of Macmillan Publishers Ltd: Nature Neuroscience. (Wig GS, Grafton ST, Demos, and Kelley WM (2005)

Reductions in neural activity underlie behavioral components of repetition priming.Nature Neuroscience 9: 1228–1233), copyright (2005).

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attribute the feeling of faster/easier processing of astimulus to a past encounter with that stimulus.A current controversy is whether amnesic patientscan be encouraged or even taught to use such fluencycues to improve their memory judgments.

See also: Cognition: An Overview of Neuroimaging

Techniques; Declarative Memory System: Anatomy;

Electroencephalography (EEG); Memory Representation;

Memory Disorders; Multiple Memory Systems.

Further Reading

Badgaiyan RD and Posner MI (1997) Time course of cortical

activations in implicit and explicit recall. Journal of Neurosci-ence 17: 4904–4913.

Bowers JS and Marsolek CJ (2003) Rethinking Implicit Memory.Oxford: Oxford University Press.

Buckner RL, Petersen SE, Ojemann JG, et al. (1995) Functional

anatomical studies of explicit and implicit memory retrievaltasks. Journal of Neuroscience 15: 12–29.

Dhond RP, Buckner RL, Dale AL, Marinkovic K, and Halgren E

(2001) Spatiotemporal maps of brain activity underlying word

generation and their modification during repetition priming.Journal of Neuroscience 10: 3564–3571.

Gabrieli JDE (1998) Cognitive neuroscience of human memory.

Annual Review of Psychology 49: 87–115.


Graf P, Squire LR, and Mandler G (1984) The information that

amnesic patients do not forget. Journal of Experimental Psy-chology: Learning, Memory and Cognition 10: 164–178.

Grill-Spector K, Henson R, and Martin A (2006) Repetition andthe brain: Neural models of stimulus-specific effects. Trends inCognitive Science 10: 14–23.

Henson RNA (2003) Neuroimaging studies of priming. Progress inNeurobiology 70: 53–81.

Jacoby LL (1983) Perceptual enhancement: Persistent effects of

an experience. Journal of Experimental Psychology: Learning,Memory and Cognition 9: 21–38.

Logan GD (1990) Repetition priming and automaticity: Common

underlying mechanisms? Cognitive Psychology 22: 1–35.

Moscovitch M (1994) Memory and working with memory: Evalu-

ation of a component process model and comparisons withother models. In: Schacter DL and Tulving E (eds.) MemorySystems, pp. 233–268. Cambridge: MIT Press.

Roediger HL and McDermott KB (1993) Implicit memory in nor-mal human subjects. In: Boller F andGrafman J (eds.)Handbookof Neuropsychology, vol. 8, pp. 63–161. Amsterdam: Elsevier.

Schacter DL (1987) Implicit memory: History and current status.

Journal of Experimental Psychology: Learning, Memory andCognition 13: 501–508.

Schott BH, Henson RN, Richardson-Klavehn A, et al. (2005)

Redefining implicit and explicit memory: The functional neuro-

anatomy of priming, remembering and control of retrieval.Proceedings of the National Academy of Sciences of UnitedStates of America 102: 1257–1262.

Schott B, Richardson-Klavehn A, Henson R, et al. (2006) Neuro-

anatomical dissociationof encoding processes related to primingand explicit memory. Journal of Neuroscience 26: 792–800.

(2009), vol. 7, pp. 1055-1063

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Squire LR (1987) Memory and Brain. New York: Oxford

University Press.

Tenpenny PL (1995) Abstractionist versus episodic theories of rep-

etition priming and word identification. Psychonomic Bulletinand Review 2: 339–363.

Wig GS, Grafton ST, Demos K, and Kelley WM (2005) Reductions

in neural activity underlie behavioral components of repetitionpriming. Nature Neuroscience 9: 1228–1233.


Relevant Website

http://en.wikipedia.org –Memory. InWikipedia: The Free Encyclo-

pedia.

e (2009), vol. 7, pp. 1055-1063

http://en.wikipedia.org

priming - cognition and brain sciences unit · phase. the critical trials used to isolate the...

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