Jason Ozubko

• PhD
• Baycrest

The production effect refers to the finding that words read aloud are better remembered than words read silently. This finding is typically attributed to the presence of additional sensorimotor features appended to the memory trace by the act of reading aloud, which are not present for items read silently. Supporting this perspective, the productio...

The production effect refers to the finding that items read aloud are better remembered than items read silently. This is often explained with reference to distinctiveness, arguing that aloud items become associated with distinctive sensorimotor features that facilitate retrieval at test. Based on this framework, more distinctive forms of productio...

The production effect is the superior memory for items read aloud as opposed to silently at the time of study. The distinctiveness account holds that produced items benefit from the encoding of additional elements associated with the act of production. If so, then that benefit should be consistent regardless of item type. Three experiments, using t...

Ongoing experience unfolds over time. To segment continuous experience into component events, humans rely on physical and conceptual boundaries. Here we explored the subjective representation of turns along travelled routes as boundaries. Across two experiments, turns selectively enhanced participants’ subjective recollection of locations immediate...

Studies have shown that when aloud and silent items are studied together, silent items are remembered more poorly than when they are studied independently. We hypothesise that this cost to silent items emerges because, at test, participants search for memories of having said items aloud and when those memory searches fail, participants become uncer...

Recent research indicates the hippocampus may code the distance to the goal during navigation of newly learned environments. It is unclear however, whether this also pertains to highly familiar environments where extensive systems-level consolidation is thought to have transformed mnemonic representations. Here we recorded fMRI while University Col...

As London taxi drivers acquire “the knowledge” and develop a detailed cognitive map of London, their posterior hippocampi (pHPC) gradually increase in volume, reflecting an increasing pHPC/aHPC volume ratio. In the mnemonic domain, greater pHPC/aHPC volume ratios in young adults have been found to relate to better recollection ability, indicating t...

Recent research indicates the hippocampus may code the distance to the goal during navigation of newly learned environments. It is unclear however, whether this also pertains to highly familiar environments where extensive systems-level consolidation is thought to have transformed mnemonic representations. Here we recorded fMRI while University Col...

The ability to represent the world accurately relies on simultaneous coarse and fine-grained neural information coding, capturing both gist and detail of an experience. The longitudinal axis of the hippocampus may provide a gradient of representational granularity in spatial and episodic memory in rodents and humans [1-8]. Rodent place cells in the...

Physical or conceptual boundaries segment continuous experience into component events. Boundaries accentuate differences between events that occur on either side of them, and reduce differences among events within them. Here we show that turns during navigation have the same effect on memory for routes as they do for episodes. Across three experime...

Increased place field size and signal autocorrelation along the dorsoventral hippocampal axis in rodents are considered a fundamental aspect of hippocampal organization, yet such evidence is lacking in humans. Using fMRI, we report corresponding evidence of increasing neural similarity from posterior to anterior hippocampus (dorsoventral homologues...

Prior representations affect future learning. Little is known, however, about the effects of recollective or familiarity-based representations on such learning. We investigate the ability to reuse or reassociate elements from recollection- and familiarity-based associations to form new associations. Past neuropsychological research suggests that hi...

Time and space represent two key aspects of episodic memories, forming the spatiotemporal context of events in a sequence. Little is known, however, about how temporal information, such as the duration and the order of particular events, are encoded into memory, and if it matters whether the memory representation is based on recollection or familia...

Five experiments explored the basis of the between-subjects production effect in recognition memory as represented by differences in the recollection and familiarity of produced (read aloud) and nonproduced (read silently) words. Using remember-know judgments (Experiment 1b) and a dual-process signal-detection approach applied to confidence ratings...

Memory can be divided into recollection and familiarity. Recollection is characterized as the ability to vividly re-experience past events, and is believed to be supported by the hippocampus, whereas familiarity is defined as an undifferentiated feeling of knowing or acquaintance, and is believed to be supported by extra-hippocampal regions, such a...

For decades, there has been controversy about whether forgetting is caused by decay over time or by interference from irrelevant information. We suggest that forgetting occurs because of decay or interference, depending on the memory representation. Recollection-based memories, supported by the hippocampus, are represented in orthogonal patterns an...

Amnesia leads to a deficit in recollection that leaves familiarity-based recognition relatively spared. Familiarity is thought to be based on the fluent processing of studied items compared to novel items. However, whether amnesic patients respond normally to direct manipulations of processing fluency is not yet known. In the current study, we mani...

Recent developments reveal that memories relying on the hippocampus are relatively resistant to interference, but sensitive to decay. The hippocampus is vital to recollection, a form of memory involving reinstatement of a studied item within its spatial-temporal context. An additional form of memory known as familiarity does not involve contextual...

In five experiments, we extended the production effect-better memory for items said aloud than for items read silently-to paired-associate learning, the goal being to explore whether production enhances associative information in addition to enhancing item information. In Experiments 1 and 2, we used a semantic-relatedness task in addition to the p...

The production effect is the finding that words spoken aloud at study are subsequently remembered better than are words read silently at study. According to the distinctiveness account, aloud words are remembered better because the act of speaking those words aloud is encoded and later recovery of this information can be used to infer that those wo...

The production effect is the superior retention of material read aloud relative to material read silently during an encoding episode. Thus far it has been explored using isolated words tested almost immediately. The goal of this study was to assess the efficacy of production as a study strategy, addressing: (a) whether the production benefit endure...

Words that are read aloud are more memorable than words that are read silently. The boundaries of this production effect (MacLeod, Gopie, Hourihan, Neary, & Ozubko, Journal of Experimental Psychology: Learning, Memory, and Cognition, 36, 671-685, 2010) have been found to extend beyond speech. MacLeod and colleagues demonstrated that mouthing also f...

The pseudoword effect is the finding that pseudowords (i.e., pronounceable nonwords) tend to give rise to more hits and false alarms than words. The familiarity-based account attributes this effect to the fact that pseudowords lack distinctive semantic meanings, which increases the inter-item similarity of pseudowords compared to words and thereby,...

In three experiments, we investigated the roles of recollection and familiarity in the production effect--the finding that words read aloud are remembered better than words read silently. Experiment 1, using the remember/know procedure, and Experiment 2, using the receiver operating characteristic procedure, converged in demonstrating that producti...

The pseudoword effect is the finding that pseudowords (i.e., rare words or pronounceable nonwords) give rise to more hits and false alarms than words. Using the retrieving effectively from memory (REM) model of recognition memory, we tested a familiarity-based account of the pseudoword effect: Specifically, the pseudoword effect arises because pseu...

The illusion of truth is traditionally described as the increase in perceived validity of statements when they are repeated (Hasher, Goldstein, & Toppino, 1977). However, subsequent work has demonstrated that the effect can arise due to the increased familiarity or fluency afforded by repetition and not necessarily to repetition per se. We examine...

The production effect is the substantial benefit to memory of having studied information aloud as opposed to silently. MacLeod, Gopie, Hourihan, Neary, and Ozubko (2010) have explained this enhancement by suggesting that a word studied aloud acquires a distinctive encoding record and that recollecting this record supports identifying a word studied...

In 8 recognition experiments, we investigated the production effect-the fact that producing a word aloud during study, relative to simply reading a word silently, improves explicit memory. Experiments 1, 2, and 3 showed the effect to be restricted to within-subject, mixed-list designs in which some individual words are spoken aloud at study. Becaus...

Is selective rehearsal possible for nonverbal information? Two experiments addressed this question using the item method directed forgetting paradigm, where the advantage of remember items over forget items is ascribed to selective rehearsal favoring the remember items. In both experiments, difficult-to-name abstract symbols were presented for stud...

When memory is contrasted for stimuli belonging to distinct stimulus classes, one of two patterns is observed: a mirror pattern, in which one stimulus gives rise to higher hits but lower false alarms (e.g., the frequency-based mirror effect) or a concordant pattern, in which one stimulus class gives rise both to higher hits and to higher false alar...

In his analysis of the pseudoword effect, [Greene, R.L. (2004). Recognition memory for pseudowords. Journal of Memory and Language, 50, 259–267.] suggests nonwords can feel more familiar that words in a recognition context if the orthographic features of the nonword match well with the features of the items presented at study. One possible account...

The mixed-list paradox is the finding that high-frequency words show a recall advantage in blocked lists, but that this advantage is reversed or nullified in mixed lists. We argue that this paradox has been poorly defined. Specifically, researchers should investigate random and alternating lists separately. We examine blocked, random, and alternati...