Assessing the distinguishability of models and the informativeness of data

A difficulty in the development and testing of psychological models is that they are typically evaluated solely on their ability to fit experimental data, with little consideration given to their ability to fit other possible data patterns. By examining how well model A fits data generated by model B, and vice versa (a technique that we call landscaping), much safer inferences can be made about the meaning of a model's fit to data. We demonstrate the landscaping technique using four models of retention and 77 historical data sets, and show how the method can be used to: (1) evaluate the distinguishability of models, (2) evaluate the informativeness of data in distinguishing between models, and (3) suggest new ways to distinguish between models. The generality of the method is demonstrated in two other research areas (information integration and categorization), and its relationship to the important notion of model complexity is discussed.     

Category specificity in normal episodic learning: applications to object recognition and category-specific agnosia

Studies of patients with category-specific agnosia (CSA) have given rise to multiple theories of object recognition, most of which assume the existence of a stable, abstract semantic memory system. We applied an episodic view of memory to questions raised by CSA in a series of studies examining normal observers' recall of newly learned attributes of familiar objects. Subjects first learned to associate arbitrarily assigned colors or textures to objects in a training phase, and then attempted to report the newly learned attribute of each object in a recall task. Our subjects' pattern of recall errors was similar both quantitatively and qualitatively to the identification deficits among patients with CSA for biological objects. Furthermore, errors tended to reflect conceptually and structurally based confusions. We suggest that object identification involves recruitment and integration of information across distributed episodic memories and that this process is susceptible to interference from objects that are structurally similar and conceptually related.     

An integrated theory of the mind

Adaptive control of thought-rational (ACT-R; J. R. Anderson & C. Lebiere, 1998) has evolved into a theory that consists of multiple modules but also explains how these modules are integrated to produce coherent cognition. The perceptual-motor modules, the goal module, and the declarative memory module are presented as examples of specialized systems in ACT-R. These modules are associated with distinct cortical regions. These modules place chunks in buffers where they can be detected by a production system that responds to patterns of information in the buffers. At any point in time, a single production rule is selected to respond to the current pattern. Subsymbolic processes serve to guide the selection of rules to fire as well as the internal operations of some modules. Much of learning involves tuning of these subsymbolic processes. A number of simple and complex empirical examples are described to illustrate how these modules function singly and in concert.     

Knowledge about the probability of change affects change detection performance

The visual system continually selects some information for processing while bypassing the processing of other information, and as a consequence, participants often fail to notice large changes to visual stimuli. In the present studies, the authors investigated whether knowledge about the probability of particular changes occurring over time increased the likelihood that changes that were likely to occur in the real world (probable changes) would be detected. The results of two experiments showed that participants were more likely to detect probable changes. This occurred whether or not they were processing the scene in a meaningful manner or actively searching the scene for changes. Furthermore, participants were unable to accurately predict change detection performance for probable and improbable changes.     

The simultaneous acquisition effect: simultaneous task learning inhibits memory for order

Delayed recall of a list of words learned simultaneously with other lists is superior to that of a list of words learned singly. A Brown-Peterson-like task was used to investigate this simultaneous acquisition effect from the perspective of the item-order distinction. It was hypothesized that simultaneous task learning would impede the encoding of order information but promote the encoding of item-specific information relative to single-task learning. The results of the first four experiments strongly supported the hypothesis that simultaneous task learning decreases the encoding of order information but provided no evidence that it facilitated the encoding of item-specific information. Additionally, Experiment 5 showed that the simultaneous acquisition effect did not occur in a mixed-list design, demonstrating an important boundary condition of the effect.     

The effect of daily stress, personality, and age on daily negative affect

The current study examined whether stress reactivity becomes stronger or weaker with age. Daily stress and daily negative affect were modeled using 1,012 subjects from the National Study of Daily Events (NSDE), an 8-day daily diary study. Age ranged from 25 to 74. Data were modeled using within-person HLM techniques. Daily stress and neuroticism interacted in their effect on daily negative affect. There was a stronger association between daily stress and negative affect for persons high in neuroticism as compared to those low on the trait. In addition, daily stress and age interacted in their effect on daily negative affect. There was a stronger association between daily stress and negative affect for older as compared to younger adults. Results suggest heightened reactivity to stressors in older adulthood, perhaps due to kindling effects. Changes in the aging brain may explain this effect. Our investigations illuminate the complexities that characterize the set of associations among negative affect, stress, personality, and age, and point to potential aging or cohort effects.     

Vicarious agency: experiencing control over the movements of others

Participants watched themselves in a mirror while another person behind them, hidden from view, extended hands forward on each side where participants' hands would normally appear. The hands performed a series of movements. When participants could hear instructions previewing each movement, they reported an enhanced feeling of controlling the hands. Hearing instructions for the movements also enhanced skin conductance responses when a rubber band was snapped on the other's wrist after the movements. Such vicarious agency was not felt when the instructions followed the movements, and participants' own covet movement mimicry was not essential to the influence of previews on reported control.     

The relationship between metacognitive awareness of olfactory ability and age in people reporting chemosensory disturbances

When determining how much to rely on olfactory information, accurate estimates of olfactory ability are important. Nevertheless, metacognitive errors regarding olfactory ability are common in the normal population. Are older adults less accurate at estimating olfactory ability, or do they simply tend to make a particular type of estimation error? We examined data from 203 patients, all of whom self-rated olfactory ability and then were tested with the Odorant Confusion Matrix. The patients' self-reports did not match the objective measure of olfactory ability in 42% of the cases, thus demonstrating a high level of impairment in metacognitive knowledge. Neither the cause of loss nor the patient's age was related to the inability to accurately estimate olfactory loss, but both contributed to the type of metacognitive errors patients made. Younger patients tended to underestimate their olfactory ability, thus behaving similarly to patients with "blindsight" who demonstrate residual visual function in the absence of awareness. Older patients tended to overestimate their olfactory ability, thus making the metacognitive error of deficit unawareness that is observed in a number of other clinical syndromes. These findings indicate that older patients are not necessarily more likely to make errors in estimating their olfactory ability; rather, they are more prone to a particular type of metacognitive error than are younger patients.     

An own gender bias and the importance of hair in face recognition

There is a large literature on the own race bias, the finding that people are better at recognizing faces of people from their own race. Here an own gender bias is shown: Males are better at identifying male faces than female faces and females are better at identifying female faces than male faces. Encoding a person's hair is shown to account for approximately half of the own gender bias when measured using hit and false alarm rates. Remember/know judgements and confidence measures are taken. Encoding a person's hair is critical for having a "remember" recollective experience. Parallels with the own race bias and implications for eyewitness testimony are discussed.