Object Priming Research Articles

Stronger adaptation of middle-to-late ERP components to object silhouette images before versus after object priming in Aphantasia

Stronger adaptation of middle-to-late ERP components to object silhouette images before versus after object priming in Aphantasia

The Affordance Directive: Affordance Priming Facilitates Object Detection Similar to Semantic Priming.

The present study investigated differences in priming perceptions of target objects via affordance or semantic primes. Affordances denote possibilities for action in relation to objects (e.g., chair - sit), whereas semantic primes describe related concepts and features of objects (e.g., chair - legs). In Experiments 1A/1B the effects of affordance and semantic priming were compared via a semantic-categorization task using a normed word list of objects. In Experiments 2-4 we investigated affordance priming on object identification of pictures using a shoebox-classification task. In Experiment 1A participants were asked to respond by categorizing the presented word as concrete or abstract. Experiment 1B was similar to 1A, but with a 1000 ms response deadline. Experiment 2 presented target objects as words or photographs. Experiment 3 presented target objects as photographs degraded at three levels (clear, medium blur, extreme blur). Experiment 4 presented target objects as photographs that began degraded and slowly became clear. Experiment 1B found word priming for semantic primes, but not affordances. In contrast, Experiments 2-4 found object priming was facilitated by both affordances and semantic primes. Collectively, our results indicate that affordances facilitate object classification.

Priming of Prepositional Phrases and Direct Objects in Spanish-Speaking Children

Purpose: The phenomenon of syntactic priming involves speakers repeating sentence structures they have recently experienced. Investigating priming can contribute to understanding of how children learn and generalize linguistic structures. This study examined the priming of two structures, direct object clitic pronouns and prepositional phrases, in Spanish-speaking children. Method: Participants were 22 typically developing monolingual Spanish-speaking children ages 4;2 (years;months)–6;3 who attended an early childhood education center in Central Mexico. For each structure, direct object clitic pronouns and prepositional phrases, children were randomly assigned to one of two groups. One group heard and repeated sentences that contained the target structure, and the other heard and repeated sentences without the target structure. Participants in both groups described pictures that could be appropriately described with or without the target structure after each prime sentence. Results: Results indicated that children were not more likely to produce sentences with an object after hearing and repeating a sentence with a direct object clitic. There was, however, a tendency for children to be more likely to produce sentences with prepositional phrases after hearing and repeating a sentence with a prepositional phrase. Conclusions: Results suggest that exposure to prepositional phrases can result in increased use of this structure in novel utterances. However, exposure to pronominal direct objects does not appear to increase production of direct objects, a finding that may relate to the nature of the pronominal object in Spanish. Findings inform our understanding of how typically developing Spanish-speaking children represent these grammatical structures.

Fluctuations of fMRI activation patterns in visual object priming

Prior information shapes how the brain processes sensory inputs (e.g., priming effects). Recent studies of "behavioral oscillation” have demonstrated that the effects of visual object primes are temporally coordinated in the theta band to guide perception efficiently. However, the neural mechanism underlying this dynamic processing remains unclear. Here, we combine functional magnetic resonance imaging (fMRI) and a time-resolved paradigm to access high-temporal-resolution profiles of brain activation fluctuations corresponding to "behavioral oscillation" in visual object priming. Specifically, multivoxel activity patterns in the fusiform face area (FFA) and the parahippocampal place area (PPA) show temporal fluctuations in the theta band (~ 5 Hz). Importantly, the theta-band power in the FFA negatively correlates with reaction time, further indicating the critical role of the observed fluctuations in brain activation. By finely mapping the temporal dynamics of cortical responses, our fMRI results demonstrate that category-selective brain areas underlie the rhythmic coordination of visual object processing.

Using eye-tracking to parse object recognition: Priming activates primarily a parts-based but also a late-emerging features-based representation.

Biederman and Cooper (Cognitive Psychology, 23, 393-419, 1991), using parts-deleted and features-deleted stimuli, presented evidence that object priming occurs at the level of the objects' parts, but not features. A control condition confirmed that some priming was accrued by the (non-visual) object concept that the stimulus represented, but all visual-level priming appeared to be at the more global level of the parts of objects, rather than the local level of the individual features (edges, vertices). This outcome has long been viewed as an important piece of supporting evidence for the existence of structural descriptions (e.g., Biederman, Psychological Review, 94, 115, 1987). The original report used a naming response task, and concluded that stimuli presenting half of the parts of an object primed only those parts, whereas half-features-deleted stimuli primed both themselves and the "complementary" half, containing the features deleted from the first image, equally. The current study adapts an eye-tracking approach to enable examination of the time course of priming across an exposure to both the primed image and unprimed competitors. Parts-deleted images primed themselves quickly and exclusively, replicating the finding of Biederman and Cooper (1991). Features-deleted images showed a deviation across time, however; initially a features-deleted prime attracted looking to itself and to its complement equally, but later on, looking to the target deviated upward, demonstrating an ability to distinguish between the two versions. The outcome of the present tests provide support for the primacy of a structural parts description, while also demonstrating the existence of multiple types of representations, both global and local.

Study\u2013test congruence of response levels in item stimulus\u2013response priming

We investigated stimulus–response (S–R) memory links during object priming using a binary associative size judgement paradigm. At study, participants decided which of two objects was bigger in real life and, at test, made the same or the reverse judgement. We examined the effects of response congruence on item S–R priming in the associative paradigm. In Experiment 1, a task reversal manipulation had minimal impact on RT priming when classifications were congruent for both recombined objects between study and test. Experiment 2 found that RT priming was more disrupted by classification incongruence of the selected than of the nonselected item alone, with incongruence of the nonselected object having no effect on RTs. Experiment 3, however, found that classification incongruence of both items eliminated RT priming, indicating that a significant effect of classification incongruence for the nonselected item is only evident if both items are classification-incongruent. Finally, across all experiments, we found that accuracy was more sensitive than RTs to decision/action incongruence. We interpret these findings in light of a two-stream account of S–R priming, and suggest a few extensions to account for interactions between S–R links of recombined items.

Electrophysiological correlates of masked repetition and conceptual priming for visual objects.

BackgroundPrevious studies have investigated the time course of visual object processing using event‐related potential (ERP) and the masked repetition priming paradigm. However, it is unclear how the ERP correlates associated with masked repetition priming differentiate from masked conceptual priming of visual objects.MethodThe present study used semantically related picture pairs of visual objects to compare the ERPs associated with masked repetition and conceptual priming of visual objects.ResultsThe results revealed that masked repetition priming was associated with N/P190 and N400 effects, whereas masked conceptual priming was only associated with N400 effect. Moreover, the topography of repetition N/P190 effect was different from repetition and conceptual N400 effects, whereas the topography of repetition N400 effect was similar to conceptual N400 effect.ConclusionsThese results indicated that masked repetition and conceptual priming were associated with spatiotemporally different ERP effects and that the N400 of visual objects was sensitive to automatic semantic spreading.

FMRI of shared-stream priming of lexical identification by object semantics along the ventral visual processing stream

Distributed sub-systems of the brain's semantic network have been shown to process semantics associated with visual features of objects (e.g., shape, colour) in the ventral visual processing stream, whereas semantics associated with actions are processed in the dorsal stream. Orthographic lexical processing has also been shown to occur in the ventral stream. Past research from our lab (Neudorf et al., 2019) has demonstrated a temporal (i.e., reaction time) priming advantage for object primes over action primes in the lexical decision task consistent with ventral shared-stream processing of visual feature object semantics and orthographic lexical identification, whereby object primes produced larger priming effects than action primes. The current experiment explored this paradigm using functional magnetic resonance imaging (fMRI) and identified the potential loci of shared-stream processing to regions in the ventral stream just anterior to colour sensitive visual area V4 cortex in the left fusiform gyrus and anterior to lexical and shape sensitive regions in the left fusiform gyrus, as well as in cerebellar lobule VI. Action priming showed more activation than object priming in dorsal stream motion related regions of the right parietal occipital junction, right superior occipital gyrus, and bilateral visual area V3. The fMRI activation observed in this experiment supports the theory that spatially shared-stream activation occurs in the ventral stream during object (but not action) priming of lexical identification, which is consistent with our earlier behavioural research showing that these processes are also temporally shared.

Functional connectivity and the failure to retrieve meaning from shape in visual object agnosia

The neural mechanisms underlying the access to object knowledge from early representations of shape are little known. Functional imaging studies support the view that representations of visual properties are distributed across occipito-temporal cortex of both cerebral hemispheres. By contrast, brain lesion studies show that focal occipito-temporal damage may lead to object agnosia – a specific impairment of object recognition. How does distributed processing fit with functional specialization implied by the existence of stimulus-specific agnosias? Using fMRI we studied functional connectivity (FC) in a patient with object agnosia following left lateral occipital damage. Despite intact global and local processing of 2D and 3D object structure, the patient made consistent object identification errors. Seven experiments testing naming, visual matching or object priming showed that his errors mainly reflected the global shape similarity between objects. Compared to controls the patient exhibited strongly reduced FC between the damaged left and the intact right medial/lateral occipital cortex. In addition, controls showed stronger connectivity between the right occipital cortex and the left and right inferior and anterior temporal cortices. Interestingly, the patient also showed compensatory increases of FC between dorsal occipital and medial parietal cortex. These findings show that focal damage to the lateral occipital cortex may have global effects on representations of objects in bilateral occipito-temporal cortex, thus supporting the view that bilaterally distributed coding is necessary for the retrieval of associative knowledge from shape.

Timing of grip and goal activation during action perception: a priming study.

Several models of action recognition acknowledge the involvement of distinct grip and goal representations in the processing of others' actions. Yet, their functional role and temporal organization are still debated. The present priming study aimed at evaluating the relative timing of grip and goal activation during the processing of photographs of object-directed actions. Action could be correct or incorrect owing to grip and/or goal violations. Twenty-eight (Experiment 1) and 25 (Experiment 2) healthy adults judged the correctness of target actions according to object typical use. Target pictures were primed by action pictures sharing the same grip or same goal, both the same grip and same goal or none. Primes were presented for 66 or 300ms in Experiment 1 and for 120 or 220ms in Experiment 2. In Experiment 1, facilitative priming effects were observed for goal and grip similarity after 300ms primes but only for goal after 66ms primes. In Experiment 2, facilitative priming effects were found for both goal and grip similarity from 120ms of prime processing. In addition, results from a control condition in Experiment 2 indicated that mere object priming could partially account for goal similarity priming effects, suggesting that object identity may help the observer to make predictions about possible action goals. Findings demonstrate an early and first activation of goal representations, as compared to grip representations, in action decoding, consistent with predictive accounts of action understanding. Future studies should determine to what extent the timing of grip and goal activation is context-sensitive.

Priming for novel object associations: Neural differences from object item priming and equivalent forms of recognition.

The neural substrates of associative and item priming and recognition were investigated in a functional magnetic resonance imaging study over two separate sessions. In the priming session, participants decided which object of a pair was bigger during both study and test phases. In the recognition session, participants saw different object pairs and performed the same size-judgement task followed by an associative recognition memory task. Associative priming was accompanied by reduced activity in the right middle occipital gyrus as well as in bilateral hippocampus. Object item priming was accompanied by reduced activity in extensive priming-related areas in the bilateral occipitotemporofrontal cortex, as well as in the perirhinal cortex, but not in the hippocampus. Associative recognition was characterized by activity increases in regions linked to recollection, such as the hippocampus, posterior cingulate cortex, anterior medial frontal gyrus and posterior parahippocampal cortex. Item object priming and recognition recruited broadly overlapping regions (e.g., bilateral middle occipital and prefrontal cortices, left fusiform gyrus), even though the BOLD response was in opposite directions. These regions along with the precuneus, where both item priming and recognition were accompanied by activation, have been found to respond to object familiarity. The minimal structural overlap between object associative priming and recollection-based associative recognition suggests that they depend on largely different stimulus-related information and that the different directions of the effects indicate distinct retrieval mechanisms. In contrast, item priming and familiarity-based recognition seemed mainly based on common memory information, although the extent of common processing between priming and familiarity remains unclear. Further implications of these findings are discussed.

Does long-term object priming depend on the explicit detection of object identity at encoding?

It is currently unclear whether objects have to be explicitly identified at encoding for reliable behavioral long-term object priming to occur. We conducted two experiments that investigated long-term object and non-object priming using a selective-attention encoding manipulation that reduces explicit object identification. In Experiment 1, participants either counted dots flashed within an object picture (shallow encoding) or engaged in an animacy task (deep encoding) at study, whereas, at test, they performed an object-decision task. Priming, as measured by reaction times (RTs), was observed for both types of encoding, and was of equivalent magnitude. In Experiment 2, non-object priming (faster RTs for studied relative to unstudied non-objects) was also obtained under the same selective-attention encoding manipulation as in Experiment 1, and the magnitude of the priming effect was equivalent between experiments. In contrast, we observed a linear decrement in recognition memory accuracy across conditions (deep encoding of Experiment 1 > shallow encoding Experiment 1 > shallow encoding of Experiment 2), suggesting that priming was not contaminated by explicit memory strategies. We argue that our results are more consistent with the identification/production framework than the perceptual/conceptual distinction, and we conclude that priming of pictures largely ignored at encoding can be subserved by the automatic retrieval of two types of instances: one at the motor level and another at an object-decision level.

Selective attention affects conceptual object priming and recognition: a study with young and older adults.

In the present study, we investigated the effects of selective attention at encoding on conceptual object priming (Experiment 1) and old–new recognition memory (Experiment 2) tasks in young and older adults. The procedures of both experiments included encoding and memory test phases separated by a short delay. At encoding, the picture outlines of two familiar objects, one in blue and the other in green, were presented to the left and to the right of fixation. In Experiment 1, participants were instructed to attend to the picture outline of a certain color and to classify the object as natural or artificial. After a short delay, participants performed a natural/artificial speeded conceptual classification task with repeated attended, repeated unattended, and new pictures. In Experiment 2, participants at encoding memorized the attended pictures and classify them as natural or artificial. After the encoding phase, they performed an old–new recognition memory task. Consistent with previous findings with perceptual priming tasks, we found that conceptual object priming, like explicit memory, required attention at encoding. Significant priming was obtained in both age groups, but only for those pictures that were attended at encoding. Although older adults were slower than young adults, both groups showed facilitation for attended pictures. In line with previous studies, young adults had better recognition memory than older adults.

Separability of abstract-category and specific-exemplar visual object subsystems: Evidence from fMRI pattern analysis

Previous research indicates that dissociable neural subsystems underlie abstract-category (AC) recognition and priming of objects (e.g., cat, piano) and specific-exemplar (SE) recognition and priming of objects (e.g., a calico cat, a different calico cat, a grand piano, etc.). However, the degree of separability between these subsystems is not known, despite the importance of this issue for assessing relevant theories. Visual object representations are widely distributed in visual cortex, thus a multivariate pattern analysis (MVPA) approach to analyzing functional magnetic resonance imaging (fMRI) data may be critical for assessing the separability of different kinds of visual object processing. Here we examined the neural representations of visual object categories and visual object exemplars using multi-voxel pattern analyses of brain activity elicited in visual object processing areas during a repetition-priming task. In the encoding phase, participants viewed visual objects and the printed names of other objects. In the subsequent test phase, participants identified objects that were either same-exemplar primed, different-exemplar primed, word-primed, or unprimed. In visual object processing areas, classifiers were trained to distinguish same-exemplar primed objects from word-primed objects. Then, the abilities of these classifiers to discriminate different-exemplar primed objects and word-primed objects (reflecting AC priming) and to discriminate same-exemplar primed objects and different-exemplar primed objects (reflecting SE priming) was assessed. Results indicated that (a) repetition priming in occipital-temporal regions is organized asymmetrically, such that AC priming is more prevalent in the left hemisphere and SE priming is more prevalent in the right hemisphere, and (b) AC and SE subsystems are weakly modular, not strongly modular or unified.

What you see depends on what you saw, and what else you saw: the interactions between motion priming and object priming.

Both visual object priming and motion priming have been reported independently, but the interactions between the two are still largely unexplored. Here we investigated this question using a novel type of SFM stimuli, 3-D helixes, and found that the motion direction perception of an ambiguous helix can be biased by the motion direction of a preceding SFM stimulus - a classic motion priming effect. However, the effectiveness of motion priming depends on object priming: a neutral object priming produced a weak motion priming, a congruent object priming led to a strong motion priming, and critically, an incongruent object priming abolished and overpowered the motion priming. In contrast, object priming alone (in the absence of motion overlap) had little effects biasing motion perception. Taken together, these results suggest that there exists an integrated neural representation of motion and structure of 3-D SFM stimuli, and motion priming of 3-D SFM stimuli might happen at an intermediate stage between MT/V5 (which is not shape selective) and LO (lateral occipital, which is not motion selective). This novel type of stimuli, 3-D helixes, along with the prime-target paradigm, thus might offer a unique tool to examine neural bases underlying the perception of 3-D SFM stimuli and perceptual priming.

The kinds of information that support novel associative object priming and how these differ from those that support item priming

We investigated how the information that supports novel associative and item object priming differs under identical study/test conditions. In Experiments 1 and 2, participants rated the meaningfulness of sentences linking two object pictures at study. At test, they performed either a size judgement or an associative recognition memory task on intact, recombined and novel picture (Experiment 1) or word (Experiment 2) associations. Associative priming was modulated by subjective meaningfulness of the encoded links, and depended on study/test perceptual overlap. In contrast, item priming was neither affected by the meaningfulness of the sentences nor by study/test changes in the stimulus presentation format. Associative priming and recognition were behaviourally dissociated, and associative recognition was probably too slow to have seriously contaminated associative priming. In Experiment 3, participants performed a perceptually oriented task during both experimental phases, and both associative and item priming were observed. These results suggest that associative priming depends on stored associative semantic and perceptual information when the test task requires flexible retrieval of associative information. Under the same conditions, item priming may only require activation of items' semantic properties. When both study and test tasks stress perceptual processing, retrieval of perceptual information is sufficient to support both kinds of priming.

FMRI evidence for dissociation between priming and conscious recognition.

Evidence from recent studies challenge traditional memory system accounts of separate mechanisms for implicit and explicit memory. The motive behind the present study was to further investigate whether common activations can be detected during explicit and implicit memory performance when using the same procedure for both tasks. Functional magnetic resonance imaging (fMRI) showed separate neural activation to perceptual repetition priming and perceptual recognition of real and nonsense objects, both in terms of the brain regions involved and in the direction of repeated-novel activations. Repetition priming showed deactivation for repeated stimuli in regions not overlapping regions activated in conscious recognition, activation patterns in the two tasks involved largely separate networks. Common activations were observed in three areas, considered as being involved in processes such as stimulus analyses, task monitoring and attention, i.e., processes external to memory. We interpret this as indicating an almost complete dissociation between the networks involved in priming and recognition memory.

Fast and slow object priming of fearful and happy facial expressions

Fast and slow object priming of fearful and happy facial expressions

Effect of repetition lag on priming of unfamiliar visual objects in young and older adults.

Across three experiments, we examined the effect of repetition lag on priming of unfamiliar visual objects in healthy young and older adults. Multiple levels of lag were examined, ranging from short (one to four intervening stimuli) to long (50 + intervening stimuli). In each experiment, subjects viewed a series of new and repeated line drawings of objects and decided whether they depicted structurally possible or impossible figures. Experiment 1 and 2 found similar levels of priming in young and older adults at short and medium lags. At the longer repetition lags (∼20 + intervening stimuli), older adults showed less overall priming, as measured by reaction time (RT) facilitation, than young adults. This indicates that older adults can rapidly encode unfamiliar three-dimensional objects to support priming at shorter lags; however, they cannot maintain these representations over longer intervals. In addition to repetition lag, we also explored the relationship between priming and cognitive reserve, as measured by education and verbal intelligence. In the older adults, higher levels of cognitive reserve were associated with greater RT priming, suggesting that cognitive reserve may mediate the relationship between aging and priming.

Neural correlates of conceptual object priming in young and older adults: an event-related functional magnetic resonance imaging study

In this event-related functional magnetic resonance imaging study, we investigated age-related differences in brain activity associated with conceptual repetition priming in young and older adults. Participants performed a speeded “living/nonliving” classification task with 3 repetitions of familiar objects. Both young and older adults showed a similar magnitude of behavioral priming to repeated objects and evidenced repetition-related activation reductions in fusiform gyrus, superior occipital, middle, and inferior temporal cortex, and inferior frontal and insula regions. The neural priming effect in young adults was extensive and continued through both the second and third stimulus repetitions, and neural priming in older adults was markedly attenuated and reached floor at the second repetition. In young adults, greater neural priming in multiple brain regions correlated with greater behavioral facilitation and in older adults, only activation reduction in the left inferior frontal correlated with faster behavioral responses. These findings provide evidence for altered neural priming in older adults despite preserved behavioral priming, and suggest the possibility that age-invariant behavioral priming is observed as a result of more sustained neural processing of stimuli in older adults which might be a form of compensatory neural activity.