Ori Friedman

Theory of mind and the right cerebral hemisphere: Refining the scope of impairment

The neuropsychological and functional characterisation of mental state attribution (“theory of mind” (ToM)) has been the focus of several recent studies. The literature contains opposing views on the functional specificity of ToM and on the neuroanatomical structures most relevant to ToM. Studies with brain-lesioned patients have consistently found ToM deficits associated with unilateral right hemisphere damage (RHD). Also, functional imaging performed with non-brain-injured adults implicates several specific neural regions, many of which are located in the right hemisphere. The present study examined the separation of ToM impairment from other deficits associated with brain injury. We tested 11 patients with unilateral right hemisphere damage (RHD) and 20 normal controls (NC) on a humour rating task, an emotion rating task, a graded (first-order, second-order) ToM task with non-mentalistic control questions, and two ancillary measures: (1) Trails A and B, in order to assess overall level of impairment and set-shifting abilities associated with executive function, and (2) a homograph reading task to assess central coherence skills. Our findings indicate that RHD can result in a functionally specific deficit in attributing intentional states, particularly those involving second-order attributions. Performance on ToM questions was not reliably related to measures of cognitive impairment; however, performance on non-ToM control questions was reliably predicted by Trails A and B. We also discuss individual RHD patients’ performance with attention to lesion locus. Our findings suggest that damage to the areas noted as specialised in neuroimaging studies may not affect ToM performance, and underscore the necessity of combining lesion and imaging studies in determining functional-anatomical relations.

Mechanisms of Belief-Desire Reasoning Inhibition and Bias

Biases in reasoning can provide insight into underlying processing mechanisms. We demonstrate a new bias in childrens belief-desire reasoning. Children between 4 and 8 years of age were told a story in which a character was mistaken about which of three boxes contained some object. The character wanted to go to one of the boxes, but only if it did not contain the object. In this scenario, the character would be expected to avoid the box where she falsely believed the object to be, but might go to either of the remaining boxes. Though the character was equally likely to go to either box, children were biased to predict that the character would go to the box that contained the object. In a control task, the character had the same desire but did not have a false belief; in this case, children showed no bias, choosing the two correct answers equally often. The observed pattern of bias was predicted by a developmental model of belief-desire reasoning. Competent belief-desire reasoning depends on a process of selection by inhibition in which the best belief content emerges from a set of candidates.

Preschoolers infer ownership from "control of permission".

Owners control permission-they forbid and permit others to use their property. So it is reasonable to assume that someone controlling permission over an object is its owner. The authors tested whether preschoolers infer ownership in this way. In the first experiment, 4- and 5-year-olds, but not 3-year-olds, chose as owner of an object a character who granted or denied another character permission to use it. In Experiment 2, older 3-year-olds chose as owner of an object a character who prevented another character from using it when prevention was accomplished by controlling permission but not otherwise. Younger 3-year-olds chose between the characters at chance. These findings indicate that preschoolers infer ownership from control of permission.

First possession: An assumption guiding inferences about who owns what

How do we determine who owns what? This article reports evidence indicating that we typically assume that the first person who possesses an object is its owner. In Experiments 1 and 2, participants read cartoons in which two children each take a turn playing with a toy. Participants selected the character who first possessed the toy when judging who owned it, but not when judging which character liked it more. In Experiment 3, participants read stories based on the Pierson v. Post (1805) property law case. In line with the appellate court’s ruling in that case, participants selected the character who first captured and possessed an animal as its owner over another character who had pursued it earlier. Together, these findings provide evidence for an assumption that specifically guides our reasoning about ownership and that may lead everyday intuitions about property to be generally consistent with property law.

A developmental shift in processes underlying successful belief-desire reasoning

Young children’s failures in reasoning about beliefs and desires, and especially about false beliefs, have been much studied. However, there are few accounts of successful belief-desire reasoning in older children or adults. An exception to this is a model in which belief attribution is treated as a process wherein an inhibitory system selects the most likely content for the belief to be attributed from amongst several competing contents [Leslie, A. M., & Polizzi, P. (1998). Developmental Science, 1 247–254]. We tested this model with an ‘avoidance false belief task’ in which subjects predict the behavior of a character, who wants to avoid an object but who is mistaken about which of three locations it is in. The task has two equally correct answers—in seeking to avoid the location where she mistakenly believes the object to be, the character might equally go to the location where the object actually is, or to the remaining empty location. However, the model predicts that subjects will prefer one of these answers, selecting the object’s actual location over the empty location. This bias was confirmed in a series of five experiments with children aged between 4 and 8 years of age. A sixth experiment ruled out two rival explanations for children’s biased responding. Two further experiments found the opposite bias in adults. These findings support one selection model as an account of belief-desire reasoning in children, and suggest that a different model is needed for adults. The process of selecting contents for mental state attributions shows a developmental shift between 8 years of age and adulthood.

Ownership and object history

Appropriate behavior in relation to an object often requires judging whether it is owned and, if so, by whom. The authors propose accounts of how people make these judgments. Our central claim is that both judgments often involve making inferences about object history. In judging whether objects are owned, people may assume that artifacts (e.g., chairs) are owned and that natural objects (e.g., pinecones) are not. However, people may override these assumptions by inferring the history of intentional acts made in relation to objects. In judging who owns an object, people may often consider which person likely possessed the object in the past--such reasoning may be responsible for peoples bias to assume that the first person known to possess an object is its owner.

First possession, history, and young children’s ownership judgments

It is impossible to perceive who owns an object; this must be inferred. One way that children make such inferences is through a first possession bias--when two agents each use an object, children judge the object belongs to the one who used it first. Two experiments show that this bias does not result from children directly inferring ownership from first possession; the experiments instead support an alternative account according to which the first possession bias reflects childrens historical reasoning. In Experiment 1, eighty-five 3- to 5-year-olds only based inferences on first possession when it was informative about the past. In Experiment 2, thirty-two 5-year-olds based ownership judgments on testimony about past contact, while disregarding testimony about future contact.

Necessary for Possession: How People Reason About the Acquisition of Ownership

For property rights to be upheld, people need to be able to judge how ownership is established. Previous research suggests that people may judge that the first person to possess an object establishes ownership over it. This article proposes and tests an alternative account, which claims that people decide who owns an object by judging who was probably necessary for the object to be possessed. Participants read stories in which one character pursues an object (e.g., an animal being hunted, a gem jutting out of a high cliff), which a second character then captures. Judgments about which character owns the object depended on which character was plausibly necessary for capturing the object. The findings support the “necessary for possession” account and suggest that people’s judgments about ownership likely depend on counterfactual reasoning or on processes akin to those used to make judgments about causality.

Just Pretending Can Be Really Learning: Children Use Pretend Play as a Source for Acquiring Generic Knowledge.

Children can acquire generic knowledge by sharing in pretend play with more knowledgeable partners. We report 3 experiments in which we investigated how this learning occurs-how children draw generalizations from pretense, and whether they resist doing so for pretense that is unrealistic. In all experiments, preschoolers watched pretend scenarios about an animal and were then asked questions about real animals. In Experiment 1, 3- and 4-year-olds treated the pretend scenarios as informative about the kind of animal represented in the pretense but as uninformative about another kind of animal. In Experiments 2 and 3, 4- and 5-year-olds resisted learning from scenarios that contradicted their existing knowledge and expectations. Together, these findings show that childrens learning from pretense shows specificity for the kinds represented in pretense and that childrens learning from pretense is selective.

Artifacts and natural kinds: children's judgments about whether objects are owned.

Peoples behavior in relation to objects depends on whether they are owned. But how do people judge whether objects are owned? We propose that people expect human-made objects (artifacts) to be more likely to be owned than naturally occurring objects (natural kinds), and we examine the development of these expectations in young children. Experiment 1 found that when shown pictures of familiar kinds of objects, 3-year-olds expected artifacts to be owned and inanimate natural kinds to be non-owned. In Experiments 2A and 2B, 3-6-year-olds likewise had different expectations about the ownership of unfamiliar artifacts and natural kinds. Children at all ages viewed unfamiliar natural kinds as non-owned, but children younger than 6 years of age only endorsed artifacts as owned at chance rates. In Experiment 3, children saw the same pictures but were also told whether objects were human-made. With this information provided, even 3-year-olds viewed unfamiliar artifacts as owned. Finally, in Experiment 4, 4- and 5-year-olds chose unfamiliar artifacts over natural kinds when judging which object in a pair belongs to a person, but not when judging which the person prefers. These experiments provide first evidence about how children judge whether objects are owned. In contrast to claims that children think about natural kinds as being similar to artifacts, the current findings reveal that children have differing expectations about whether they are owned.