Declarative memory permits an organism to recognize stimuli that have been previously encountered, discriminating them from those that are novel. One basis for recognition is item memory strength, which may support the perception of stimulus familiarity. Though the medial temporal lobes are known to be critical for declarative memory, at present the neural mechanisms supporting perceived differ...

If memory depends on changes in synaptic strength, then manipulation of synaptic strength after learning should alter memory for what was learned. Here, we examined whether high frequency stimulation of the perforant path in vivo disrupts memory for a previously-learned hidden platform location in the Morris water task as well as whether this effect is modulated by memory strength or memory rea...

Models of recognition memory assume that memory decisions are based partially on the subjective strength of the test item. Models agree that the subjective strength of targets increases with additional time for encoding however the origin of the subjective strength of foils remains disputed. Under the fixed strength assumption the distribution of memory strength for foils is invariant across ex...

The study of list length effects (adding items to a list affects memory for the other items) and list strength effects (strengthening some items in a list affects memory for the nonstrengthened items) is important to constrain models of memory. In recognition memory, a list length effect is generally found, whereas a list strength effect is not. Using the switched-plurality procedure in an old-...

It has been suggested that hippocampal activity predicts subsequent recognition success when recognition decisions are based disproportionately on recollection, whereas perirhinal activity predicts recognition success when decisions are based primarily on familiarity. Another perspective is that both hippocampal and perirhinal activity are predictive of overall memory strength. We tested the re...

Although commonly used, the term memory strength is not well defined in humans. Besides durability, it has been conceptualized by retrieval characteristics, such as subjective confidence associated with retrieval, or objectively, by the amount of information accurately retrieved. Behaviorally, these measures are not necessarily correlated, indicating that distinct neural processes may underlie ...

Familiarity, or memory strength, is a central construct in models of cognition. In previous categorization and long-term memory research, correlations have been found between psychological measures of memory strength and activation in the medial temporal lobes (MTLs), which suggests a common neural locus for memory strength. However, activation alone is insufficient for determining whether the ...