On the relationship between visual imagery and visual perception: Evidence from priming studies

Two priming experiments using a perceptual identification task were conducted to explore the functional and representational overlap between visual imagery and visual perception. The first experiment included a study phase in which primes were either perceived or imaged objects and a perceptual identification test task in which targets were parts of studied and non-studied objects. Imagery primed identification when subjects were instructed to count the parts of the imaged objects in the study phase but not when they were instructed to focus on the global shape of the imaged objects. This result suggests that imagery involves perceptual representations identical to those involved in perception. It also suggests that the representational overlap between imagery and perception depends on the type of images generated, as some images may consist in global shapes only, whereas others may consist in detailed, multi-part shapes. In the second experiment, we used whole objects as target stimuli which provided subjects with more information to identify masked targets and thereby reduced top-down processing. Priming from imagery fell beneath significance, suggesting that this sort of priming is elicited in a large part by a transfer of top-down processes from study to test.     

Don't Predict the Future–Direct it! Comments on the intellectual history,the Logical and Applicative Visibility,and the Underlying Assumptions of Directed Evolution (DE)

The best way to predict the future is to invent it.

—Alan Kay ¹ 1. Alan Kay is one of the inventors of the Smalltalk programming language and one of the originators of the idea of Object Oriented Programming. He is the conceiver of the laptop computer and the architect of the modern windowing GUI.

It is obvious that there are patterns of cultural change—evolution in the neutral sense—and any theory of cultural change worth more than a moment's consideration will have to be Darwinian in the minimal sense of being consistent with the theory of evolution by natural selection of Homo sapiens.

—Daniel Dennett ² 2. Daniel C. Dennett is a Professor of Philosophy and Director of the Center for Cognitive Studies at Tufts University. He is the author of several books, including Consciousness Explained (1991), Darwin's Dangerous Idea (1995), and Kinds of Minds (1996). This quote is taken from his forward to Darwinizing Culture (Aunger 2000 Aunger, R. 2000. Darwinizing culture: The status of memetics as a science, Oxford and New York: Oxford University Press.  [Google Scholar], ix).

The future is here. It's just not widely distributed yet.

—William Gibson ³ 3. In the early 1980s William Gibson wrote Neuromancer, coining the term “cyberspace” to describe computer-generated virtual realities long before we saw the similarities with today's Internet.

It is the magician's wand, by means of which he may summon into life whatever form and mould he pleases.

—Charles Darwin commenting on the power of artificial selection ⁴ 4. Here Darwin is explaining the power of artificial selection and its potential for the directed evolution of biological systems (domestication and commercially oriented breeding) in his Origin of Species (1859, 68).      

The role of item similarity in part-list cueing impairment

The presentation of a subset of studied items as retrieval cues can have detrimental effects on recall of the remaining (target) items. In three experiments we examined whether such part-list cueing impairment depends on the similarity between cue and target items. Item similarity was manipulated by making use of pre-experimental semantic similarities between cue and target items (Experiments 1 and 2), or was episodically induced through a similarity-encoding task, in which participants were asked to interrelate cue and target items in a meaningful way (Experiment 3). In all three experiments reliable part-list cueing impairment arose when the similarity between cues and targets was low, but no impairment was found when the similarity between cues and targets was high. Inhibitory as well as non-inhibitory explanations of the findings are discussed.     

Constructing autobiographical events within a spatial or temporal context: a comparison of two targeted episodic induction techniques

ABSTRACT

Recalling and imagining autobiographical experiences involves constructing event representations within spatiotemporal contexts. We tested whether generating autobiographical events within a primarily spatial (where the event occurred) or temporal (the sequence of actions that occurred) context affected how the associated mental representation was constructed. We leveraged the well-validated episodic specificity induction (ESI) technique, known to influence the use of episodic processes on subsequent tasks, to develop variants that selectively enhance spatial or temporal processing. We tested the effects of these inductions on the details used to describe past and future autobiographical events. We first replicated the standard ESI effect, showing that ESI enhances generating episodic details, particularly those that are perception-based, when describing autobiographical events (Experiment 1). We then directly compared the effects of the spatial and temporal inductions (Experiment 2 and 3). When describing autobiographical events, spatial induction enhanced generating episodic details, specifically perception-based details, compared to the control or temporal inductions. A greater proportion of the episodic details generated after the temporal induction were gist-based than after the spatial induction, but this proportion did not differ from a control induction. Thus, using a spatial or temporal framework for autobiographical event generation alters the associated details that are accessed.     

Evidence that an episodic mode of thinking facilitates encoding of perceptually rich memories for naturalistic events relative to a gist-based mode of thinking

ABSTRACT

Several studies have demonstrated that an episodic specificity induction (ESI) can influence cognitive abilities that involve episodic processes at retrieval. To better understand the downstream implications of an “episodic mode of thinking,” we investigate whether an ESI influences encoding of new events. In a between-subjects design, participants were given an ESI or gist (control) induction. In an ostensibly unrelated task, participants then were shown film clips of naturalistic events. After a filled delay, participants were given a surprise memory test, which required narrative recollection of the film clips. Participants who received the ESI generated narratives that contained more perceptual details specifically. Relative to gist thinking, an episodic mode of thinking appears to facilitate encoding of perceptually rich memories for naturalistic events.     

The self in autobiographical memory: Effects of self-salience on narrative content and structure

Contemporary models of autobiographical memory attribute a prominent role to the conceptualisation of the self. In an attempt to better understand the impact of the self as an organising feature of autobiographical memory, narratives of personal episodes were elicited, either after a questionnaire about the self (self-prime condition) or after a distractor task (control condition). Participants also wrote a narrative of a turning-point memory, which is by definition a self-focused narrative. Narratives were divided into propositions and analysed for the types of statements used. As predicted, when writing self-focused turning-point narratives participants included more statements relating to the meaning of an event and connecting it to the self, and fewer statements focusing on the who, what, where, and when of the narrative. Narratives written after the self-prime also demonstrated characteristics that were similar to turning-point narratives, although not on all measures. This shift in narrative focus in turning-point and self-primed memory narratives indicates an increased attempt to fulfil goals of coherence rather than correspondence (Conway, 2005). These findings lend insight into the nature of the relationship between the semantic conceptualisation of the self, and the process of retrieving event-specific knowledge in episodic memory.     

Distinct and shared cognitive functions mediate event- and time-based prospective memory impairment in normal ageing

Prospective memory (PM) is the ability to remember to perform an action at a specific point in the future. Regarded as multidimensional, PM involves several cognitive functions that are known to be impaired in normal ageing. In the present study we set out to investigate the cognitive correlates of PM impairment in normal ageing. Manipulating cognitive load, we assessed event- and time-based PM, as well as several cognitive functions, including executive functions, working memory, and retrospective episodic memory, in healthy participants covering the entire adulthood. We found that normal ageing was characterised by PM decline in all conditions and that event-based PM was more sensitive to the effects of ageing than time-based PM. Whatever the conditions, PM was linked to inhibition and processing speed. However, while event-based PM was mainly mediated by binding and retrospective memory processes, time-based PM was mainly related to inhibition. The only distinction between high- and low-load PM cognitive correlates lies in an additional, but marginal, correlation between updating and the high-load PM condition. The association of distinct cognitive functions, as well as shared mechanisms with event- and time-based PM, confirm that each type of PM relies on a different set of processes.     

Mnemonic benefits of retrieval practice at short retention intervals

The testing effect refers to the retention benefit conferred by prior retrieval of information from memory. Although the testing effect is a robust phenomenon, a common assumption is that reliable memory benefits only emerge after long retention intervals of days or weeks. The present study focused on potential test-induced retention benefits for brief retention intervals on the order of minutes and tens of seconds. Participants in four experiments studied lists of words. Some of the items were subjected to an initial cued recall test, and others were re-presented for additional study. Free recall tests were administered in each experiment following retention intervals ranging from 30 s to 8 min. When initial retrieval practice was successful (Experiments 1 through 3), or feedback compensated for unsuccessful retrieval (Experiment 4), significant testing effects emerged at all retention intervals. Results are discussed in the context of a bifurcated item-distribution model and highlight the importance of initial test performance and the type of analysis employed when examining testing effect data.     

Constrained prose recall and the assessment of long-term forgetting: The case of ageing and the Crimes Test

It has become increasingly clear that some patients with apparently normal memory may subsequently show accelerated long-term forgetting (ALF), with dramatic loss when retested. We describe a constrained prose recall task that attempts to lay the foundations for a test suitable for detecting ALF sensitively and economically. Instead of the usual narrative structure of prose recall tests, it employs a matrix structure involving four episodes, each describing a minor crime, with each crime involving the binding into a coherent episode of a specified range of features, involving the victim, the crime, the criminal and the location, allowing a total of 80 different probed recall questions to be generated. These are used to create four equivalent 20-item tests, three of which are used in the study. After a single verbal presentation, young and elderly participants were tested on three occasions, immediately, and by telephone after a delay of 6 weeks, and at one of a varied range of intermediate points. The groups were approximately matched on immediate test; both showed systematic forgetting which was particularly marked in the elderly. We suggest that constrained prose recall has considerable potential for the study of long-term forgetting.