A return of mental imagery: The pictorial theory of visual perspective-taking.

The pictorial theory of mental imagery was a central concern of cognitive science during the latter years of the last century. Proponents of the theory argued that images are reinterpreted by the same processes that act upon perceptual inputs. This idea has recently re-emerged within the context of visual perspective-taking. The perceptual simulation theory argues that an observer not only generates an image of what another individual sees but the image is used by the perceptual system in a bottom-up manner. Based on the assumption of Kosslyn and colleagues, we argue that a minimum requirement of a pictorial theory of visual perspective-taking is that observers must faithfully represent relative distance between different points of a scene as would be viewed from an alternative position. The available evidence does not however support this. We conclude that the latest attempt to give mental imagery causal status in a cognitive process is unwarranted.

Perirhinal cortex and the recognition of relative familiarity.

Spontaneous object recognition (SOR) is a widely used task of recognition memory in rodents which relies on their propensity to explore novel (or relatively novel) objects. Network models typically define perirhinal cortex as a region required for recognition of previously seen objects largely based on findings that lesions or inactivations of this area produce SOR deficits. However, relatively little is understood about the relationship between the activity of cells in the perirhinal cortex that signal novelty and familiarity and the behavioural responses of animals in the SOR task. Previous studies have used objects that are either highly familiar or absolutely novel, but everyday memory is for objects that sit on a spectrum of familiarity which includes objects that have been seen only a few times, or objects that are similar to objects which have been previously experienced. We present two studies that explore cellular activity (through c-fos imaging) within perirhinal cortex of rats performing SOR where the familiarity of objects has been manipulated. Despite robust recognition memory performance, we show no significant changes in perirhinal activity related to the level of familiarity of the objects. Reasons for this lack of familiarity-related modulation in perirhinal cortex activity are discussed. The current findings support emerging evidence that perirhinal responses to novelty are complex and that task demands are critical to the involvement of perirhinal cortex in the control of object recognition memory.

The NMDA receptor antagonist MK-801 fails to impair long-term recognition memory in mice when the state-dependency of memory is controlled.

NMDA receptor-dependent synaptic plasticity has been proposed to be important for encoding of memories. Consistent with this hypothesis, the non-competitive NMDA receptor antagonist, MK-801, has been found to impair performance on tests of memory. Interpretation of some of these findings has, however, been complicated by the fact that the drug-state of animals has differed during encoding and tests of memory. Therefore, it is possible that MK-801 may result in state-dependent retrieval or expression of memory rather than actually impairing encoding itself. We tested this hypothesis in mice using tests of object recognition memory with a 24-hour delay between the encoding and test phase. Mice received injections of either vehicle or MK-801 prior to the encoding phase and the test phase. In Experiment 1, a low dose of MK-801 (0.01 mg/kg) impaired performance when the drug-state (vehicle or MK-801) of mice changed between encoding and test, but there was no significant effect of MK-801 on encoding. In Experiment 2, a higher dose of MK-801 (0.1 mg/kg) failed to impair object recognition memory when mice received the drug prior to both encoding and test compared to mice that received vehicle. MK-801 did not affect object exploration, but it did induce locomotor hyperactivity at the higher dose. These results suggest that some previous demonstrations of MK-801 effects may reflect a failure to express or retrieve memory due to the state-dependency of memory rather than impaired encoding of memory.

Incidental context information increases recollection.

The current study describes a receiver-operating characteristic (ROC) task for human participants based on the spontaneous recognition memory paradigms typically used with rodents. Recollection was significantly higher when an object was in the same location and background as at encoding, a combination used to assess episodic-like memory in animals, but not when only one of these task-irrelevant cues was present. The results show that incidentally encoded cue information can determine the degree of recollection, and opens up the possibility of assessing recollection across species in a single experimental paradigm, allowing better understanding of the cognitive and biological mechanisms at play.

Self-referential memory in autism spectrum disorder and typical development: Exploring the ownership effect.

Owned objects occupy a privileged cognitive processing status and are viewed almost as extensions of the self. It has been demonstrated that items over which a sense of ownership is felt will be better remembered than other items (an example of the "self-reference effect"). As autism spectrum disorder (ASD) is characterised by an a typical self-concept, people with ASD may not demonstrate this "ownership effect". Two experiments were conducted which replicate and extend Cunningham, Turk, MacDonald, and Macrae (2008). In Experiment 1, neurotypical adults completed a card sorting task and cards belonging to the 'self' were better remembered than cards belonging to another person. In Experiment 2, adults with ASD recalled self- and other owned items equally well. These results shed light both on the relation between sense of self and the ownership effect, and the nature of the self-concept in ASD.

The episodic nature of episodic-like memories.

Studying episodic memory in nonhuman animals has proved difficult because definitions in humans require conscious recollection. Here, we assessed humans' experience of episodic-like recognition memory tasks that have been used with animals. It was found that tasks using contextual information to discriminate events could only be accurately performed using recollection, not familiarity. However, tasks using temporal information to discriminate events could be accurately performed using either recollection or familiarity. The results strengthen the position that some episodic-like recognition memory tasks are a valid model of episodic memory. However, tasks that rely on temporal information may be susceptible to nonepisodic strategies.

It's Not You, It's Me: A Review of Individual Differences in Visuospatial Perspective Taking.

Visuospatial perspective taking (VSPT) concerns the ability to understand something about the visual relationship between an agent or observation point on the one hand and a target or scene on the other. Despite its importance to a wide variety of other abilities, from communication to navigation, and decades of research, there is as yet no theory of VSPT. Indeed, the heterogeneity of results from different (and sometimes the same) VSPT tasks point to a complex picture suggestive of multiple VSPT strategies, individual differences in performance, and context-specific factors that together have a bearing on both the efficiency and accuracy of outcomes. In this article, we review the evidence in search of patterns in the data. We found a number of predictors of VSPT performance but also a number of gaps in understanding that suggest useful pathways for future research and, possibly, a theory (or theories) of VSPT. Overall, this review makes the case for understanding VSPT by better understanding the perspective taker rather than the target agents or their perception.

Teleporting into walls? The irrelevance of the physical world in embodied perspective-taking.

Embodied theories of Level 2 visual perspective-taking usually assume that we imagine ourselves in other real-world locations to take perspectives. We tested this assertion by giving participants an embodied perspective-taking task in which they were instructed to make manual responses based on imagined perspectives. Importantly, on half of the trials, the location of the alternative perspective was not physically possible (i.e., blocked with a wall). Across two experiments, results showed that participants performed just as well for the physically impossible perspectives as for accessible ones. We interpret these data as evidence that embodied perspective-taking is agnostic to local physical features of our environment.

Evidence for a Weak but Reliable Processing Advantage for False Beliefs Over Similar Nonmental States in Adults.

The ability to understand the mental states of others has sometimes been attributed to a domain-specific mechanism which privileges the processing of these states over similar but nonmental representations. If correct, then others' beliefs should be processed more efficiently than similar information contained within nonmental states. We tested this by examining whether adults would be faster to process others' false beliefs than equivalent "false" photos. Additionally, we tested whether they would be faster to process others' true beliefs about something than their own (matched) personal knowledge about the same event. Across four experiments, we found a small but reliable effect in favor of the first prediction, but no evidence for the second. Results are consistent with accounts positing specialized processes for (false) mental states. The size of the effect does, however, suggest that alternative explanations such as practice effects cannot be ruled out.

Visual perspective taking without visual perspective taking.

What happens when an observer takes an agent's visual perspective of a scene? We conducted a series of experiments designed to measure what proportion of adults take a stimulus-centered rather than agent-centered approach to a visual perspective taking task. Adults were presented with images of an agent looking at a number (69). From the perspective of the viewer, the number appeared upside down. We then asked participants what number the agent saw. An agent-centered approach, that is, one that takes into account the other's visual experience, should produce the correct answer "69". Even an egocentric error (i.e., the participant's own perspective) would provide the same correct response. We were interested in what proportion of participants would give the incorrect answer "96", which is best explained by a stimulus-centered rather than agent-centered strategy, namely "flipping" each digit one at a time from left to right. Crucially, such a strategy ignores the alternative visual perspective. We found that, on average, 12-21% of participants made this error. We discuss this finding in the context of the key questions around representation, content, and Theory of Mind in visual perspective taking. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Medial septal cholinergic neurons are necessary for context-place memory but not episodic-like memory.

Loss of cholinergic cortical input is associated with diseases in which episodic memory impairment is a prominent feature, but the degree to which this neurochemical lesion can account for memory impairment in humans with neurodegenerative diseases remains unclear. Removal of cholinergic input to hippocampus impairs some of its functions in memory, perhaps by reducing the plasticity of information representation within the hippocampus, but the role of cholinergic hippocampal input in episodic-like memories has not been investigated. To address this question, we tested rats with selective lesions of basal forebrain neurons in the medial septum and vertical limb of the diagonal band (MS/VDB), which contains hippocampal-projecting cholinergic neurons, on a task of integrated memory for objects, places, and contexts ("what-where-which" memory). This task serves as a rodent model of human episodic memory (episodic-like memory) and is sensitive to damage to the hippocampal system. Rats with lesions of cholinergic MS/VDB neurons performed as well on the what-where-which task as controls, but were impaired in a task that simply required them to associate places with contexts ("where-which" memory). Thus, episodic-like memories that rely on the hippocampus do not require cholinergic neuromodulation to be formed. Nevertheless, some more specific aspects of where-which memory, which may be more dependent on the plasticity of hippocampal spatial representations, require acetylcholine. These results suggest that cholinergic projections to hippocampus are not necessary for episodic memory and, furthermore, that hippocampal spatial representations may be to some extent dissociable from episodic memory function.

Visual recognition memory across contexts.

In two experiments, we investigated the development of representational flexibility in visual recognition memory during infancy using the Visual Paired Comparison (VPC) task. In Experiment 1, 6- and 9-month-old infants exhibited recognition when familiarization and test occurred in the same room, but showed no evidence of recognition when familiarization and test occurred in different rooms. In contrast, 12- and 18-month-old infants exhibited recognition irrespective of testing room. Thus, flexibility across a change of room was observed at a younger age than flexibility across a change of background that has previously been seen with the VPC procedure (Robinson & Pascalis, 2004). To determine if limitations in representational flexibility across a change of background could be overcome by experiences during encoding, in Experiment 2, 6-, 9-, 12- and 18-month-old infants were familiarized with a picture on multiple backgrounds. At all ages, infants showed recognition across a change in background at test. These findings indicate that dissociating an item from its context during encoding may be an important factor in understanding the representational flexibility of visual recognition memory in infancy. Developmental changes in representational flexibility are likely driven by changes in the functional maturity of the hippocampal formation, and experience.

Visual perspective-taking and image-like representations: We don't see it.

The ability to represent another agent's visual perspective has recently been attributed to a process called "perceptual simulation", whereby we generate an image-like or "quasi-perceptual" representation of another agent's vision. In an extensive series of experiments we tested this notion. Adult observers were presented with pictures of an agent looking at two horizontal lines, one of which was closer to the agent and hence appeared longer from his/her visual perspective. In each case approximately as many participants judged the closer line to appear shorter as longer (to the agent), i.e., failures to take the agent's perspective. This occurred when clear depth cues were added to emphasise the agent's location relative to the stimuli, when the agent was moved closer to the lines, when the lines were oriented vertically, when judgments could be made while viewing the image, and when participants imagined themselves in the agent's place. It also persisted when we asked participants to imagine what a photo taken from the same location as the agent would show, ruling out a misinterpretation of the instructions. Overall, our data suggest that adults attempt to solve visual perspective-taking problems by drawing upon naïve and often erroneous ideas about how vision works.

'Seeing' proximal representations: Testing attitudes to the relationship between vision and images.

Corrections applied by the visual system, like size constancy, provide us with a coherent and stable perspective from ever-changing retinal images. In the present experiment we investigated how willing adults are to examine their own vision as if it were an uncorrected 2D image, much like a photograph. We showed adult participants two lines on a wall, both of which were the same length but one was closer to the participant and hence appeared visually longer. Despite the instruction to base their judgements on appearance specifically, approximately half of the participants judged the lines to appear the same. When they took a photo of the lines and were asked how long they appeared in the image their responses shifted; now the closer line appeared longer. However, when they were asked again about their own view they reverted to their original response. These results suggest that many adults are resistant to imagining their own vision as if it were a flat image. We also place these results within the context of recent views on visual perspective-taking.

Two independent sources of difficulty in perspective-taking/theory of mind tasks.

Many perspective-taking and theory of mind tasks require participants to pass over the answer that is optimal from the self-perspective. For instance, in the classic change-of-location (false belief) task, participants are required to ignore where they know the object to be, and in the director task participants are required to ignore the best match for the instruction the other, less knowledgeable agent gives them (e.g., 'the top cup'). However, a second but equally critical requirement in such tasks is the ability to select a response which is wrong from the self-perspective; where the object is not, or an object that does not match the instruction (e.g., the middle cup instead of the top cup from one's own perspective). We present the results of an experiment that teases apart these two effects and demonstrate that both contribute independently to the difficulty in taking other perspectives. Reanalyses of data from previous experiments confirm this dual effect. These results suggest a revision of our understanding of egocentricity and difficulty in perspective-taking generally.

Impaired episodic simulation in a patient with visual memory deficit amnesia.

For the first time, we assess episodic simulation in a patient with visual memory deficit amnesia, following damage to visual association cortices. Compared to control participants, the patient with visual memory deficit amnesia shows severely restricted responses when asked to simulate different types of future episodic scenarios. Surprisingly, the patient's responses are more limited in cases where the scenarios require less reliance on visual information. We explain this counterintuitive finding through discussing how the severe retrograde amnesia in visual memory deficit amnesia limits the patient's access to episodic memories in which vision has not been a focus of their life. As a result, we argue that the deficits in visual memory deficit amnesia continue to distinguish it from amnesia after direct damage to the hippocampus.

Perspective-Taking: In Search of a Theory.

Perspective-taking has been one of the central concerns of work on social attention and developmental psychology for the past 60 years. Despite its prominence, there is no formal description of what it means to represent another's viewpoint. The present article argues that such a description is now required in the form of theory-a theory that should address a number of issues that are central to the notion of assuming another's viewpoint. After suggesting that the mental imagery debate provides a good framework for understanding some of the issues and problems surrounding perspective-taking, we set out nine points that we believe any theory of perspective-taking should consider.

Recollection is impaired, but familiarity remains intact in rats with lesions of the fornix.

It has been argued that a neural system including the hippocampus, fornix, mamillary bodies, and anterior thalamus is specifically involved in recollection, but not in familiarity based memory processes. Here we test this hypothesis using a task of episodic-like memory within an E-shaped maze. Animals seek out a preferred object (what) in a particular location (where) that is unique to a particular context (which occasion). As objects are hidden from view at the point of decision making, the animals can only base their decision on recall of their previous episode in the E-shaped maze. In contrast, once a decision has been made animals are free to explore both objects and display an object preference when objects are visible to the animal and decisions can be made on the basis of familiarity. Animals with fornix lesions are impaired at recalling a past event. However, the same animals on the same trials show no such impairment in a judgement of familiarity. We therefore demonstrate that recall is dependent upon the fornix, while familiarity based memory is not.

Grammatical gender and linguistic relativity: A systematic review.

Many languages assign nouns to a grammatical gender class, such that "bed" might be assigned masculine gender in one language (e.g., Italian) but feminine gender in another (e.g., Spanish). In the context of research assessing the potential for language to influence thought (the linguistic relativity hypothesis), a number of scholars have investigated whether grammatical gender assignment "rubs off" on concepts themselves, such that Italian speakers might conceptualize beds as more masculine than Spanish speakers do. We systematically reviewed 43 pieces of empirical research examining grammatical gender and thought, which together tested 5,895 participants. We classified the findings in terms of their support for this hypothesis and assessed the results against parameters previously identified as potentially influencing outcomes. Overall, we found that support was strongly task- and context-dependent, and rested heavily on outcomes that have clear and equally viable alternative explanations. We also argue that it remains unclear whether grammatical gender is in fact a useful tool for investigating relativity.

Walking through doorways differentially affects recall and familiarity.

Previous research has reported that walking through a doorway to a new location makes memory for objects and events experienced in the previous location less accurate. This effect, termed the location updating effect, has been used to suggest that location changes are used to mark boundaries between events in memory: memories for objects encountered within the current event are more available than those from beyond an event boundary. Within a computer-generated memory task, participants navigated through virtual rooms, walking through doorways, and interacting with objects. The accuracy and their subjective experience of their memory for the objects (remember/know and confidence) were assessed. The findings showed that shifts in location decreased accurate responses associated with the subjective experience of remembering but not those associated with the experience of knowing, even when considering only the most confident responses in each condition. These findings demonstrate that a shift in location selectively impacts recollection and so contributes to our understanding of boundaries in event memory.