A dissociation between causal judgement and the ease with which a cause is categorized with its effect

The associative view of human causal learning argues that causation is attributed to the extent that the putative cause activates, via an association, a mental representation of the effect. That is, causal learning is a human analogue of animal conditioning. We tested this associative theory using a task in which a fictitious character suffered from two allergic reactions, rash (O₁) and headache (O₂). In a conditioned inhibition design with each of these two outcomes (A-O₁/AX- and B-O₂/BY-), participants were trained that one herbal remedy (X) prevented O₁ and that the other (Y) prevented O₂. These inhibitory properties were revealed in a causal judgement summation test. In a subsequent categorization task, X was most easily categorized with O_1, and Y with O₂. Thus, the categorization data indicated an excitatory X-O₁ and Y-O₂ association, the reverse of the inhibitory relationship observed on the causal judgement measure. A second experiment showed that this pattern of excitation and inhibition is dependent on intermixed A-O₁ and AX- trials. These results are problematic for the standard application of associative activation theories to causal judgement. We argue instead that the inhibition revealed in the causal judgement task reflects inferential reasoning, which relies, in part, on the ability of the cue in question to excite a representation of the outcome, as revealed in the categorization test.     

Shallow processing of ambiguous pronouns: evidence for delay

Two self-paced reading-time experiments examined how ambiguous pronouns are interpreted under conditions that encourage shallow processing. In Experiment 1 we show that sentences containing ambiguous pronouns are processed at the same speed as those containing unambiguous pronouns under shallow processing, but more slowly under deep processing. We outline three possible models to account for the shallow processing of ambiguous pronouns. Two involve an initial commitment followed by possible revision, and the other involves a delay in interpretation. In Experiment 2 we provide evidence that supports the delayed model of ambiguous pronoun resolution under shallow processing. We found no evidence to support a processing system that makes an initial commitment to an interpretation of the pronoun when it is encountered. We extend the account of pronoun resolution proposed by Rigalleau, Caplan, and Baudiffier (2004) to include the treatment of ambiguous pronouns under shallow processing.     

Transformation of the discriminative and eliciting functions of generalized relational stimuli

In three experiments, match-to-sample procedures were used with undergraduates to establish arbitrary relational functions for three abstract visual stimuli. In the presence of samples A, B, and C, participants were trained to select the smallest, middle, and largest member, respectively, of a series of three-comparison arrays. In Experiment 1, the B (choose middle) stimulus was then used to train a steady rate of keyboard pressing before the A (choose smallest) and the C (choose largest) stimuli were presented. Participants pressed slower to A and faster to C than to B. Then B was paired with mild shock in a Pavlovian procedure with skin conductance change as the dependent variable. When presented with A and C, 6 of 8 experimental participants showed smaller skin conductance changes to A and larger skin conductance changes to C than to B. In Experiment 2, A was then used as a sample in a match-to-sample procedure to establish an arbitrary size ranking among four same-sized colored circle comparisons. One of the middle circles was then used to establish a steady rate of pressing before the other circles were presented. Five of 6 participants responded slower to the "smaller" circle and faster to the "larger" circle than they did to the "middle" circle. In Experiment 3, A, B, and C were then presented on a series of test trials requiring participants to pick the comparison that was less than, greater than, or equal to the sample. Novel stimuli were included on some trials. Results indicated that the relational training procedures produced derived relations among the stimuli used in training and that these allowed correct inferences of relative size ranking among novel stimuli.     

The effects of relative intensity of cue and marker on marked trace conditioning in pigeons

Pigeons were trained on trace conditioning procedures (autoshaping) in which a keylight conditioned stimulus (CS) was presented for 5 sec and followed after a 10-sec temporal gap by food. In Experiment 1, acquisition of conditioned responding to the CS was facilitated when it was immediately followed by a brief stimulus, but only when the brief stimulus was of greater intensity than the trace CS. In Experiment 2, this facilitation effect was found when a more intense brief stimulus followed the trace CS immediately, but not when it was delayed. In both experiments, responding to the target CS was compared within-subjects to that to a control CS, which eliminated factors such as second-order conditioning as an explanation for the facilitation effects. Together, the results of Experiments 1 and 2 suggest that a brief stimulus may mark immediately preceding events in memory and thus facilitate their association with delayed reinforcement only if the brief stimulus is relatively more intense, and thus more salient, than the target events. In Experiment 3, we found substantial generalization of this facilitation effect from the marked CS to the control CS and conclude that the results of Experiments 1 and 2 may underestimate the magnitude of these marking effects.     

Spousal caregiver confidence and recovery from ambulatory activity limitations in stroke survivors.

OBJECTIVE: This study examined whether spousal confidence in care-recipient recovery can predict recovery from activity limitations following stroke and how spousal confidence relates to stroke survivor self-efficacy for recovery. DESIGN: A prospective design was used. Measures were gathered from stroke survivor/spouse dyads at two time points, both postdischarge from the hospital following stroke (N=109). MAIN OUTCOME MEASURES: The dependent variable was recovery from ambulatory activity limitations over 6 weeks, as measured by the Functional Limitations Profile. A single spousal confidence item was tailored to an ambulatory behavior that the stroke survivors could not perform at Time 1. RESULTS: Spousal confidence was correlated with ambulation recovery (r=-0.23, p<.05) and stroke survivor self-efficacy for recovery (r=.25, p<.05). Higher spousal confidence was associated with a better recovery and greater stroke survivor self-efficacy for recovery, but not with initial health status or practical support received. CONCLUSION: The relationship between caregiver confidence, care-recipient self-efficacy for recovery, and recovery outcomes needs further elucidation.     

Traditional difference-score analyses of reasoning are flawed

Studies of the belief bias effect in syllogistic reasoning have relied on three traditional difference score measures: the logic index, belief index, and interaction index. Dube, Rotello, and Heit (2010, 2011) argued that the interaction index incorrectly assumes a linear receiver operating characteristic (ROC). Here, all three measures are addressed. Simulations indicated that traditional analyses of reasoning experiments are likely to lead to incorrect conclusions. Two new experiments examined the role of instructional manipulations on the belief bias effect. The form of the ROCs violated assumptions of traditional measures. In comparison, signal detection theory (SDT) model-based analyses were a better match for the form of the ROCs, and implied that belief bias and instructional manipulations are predominantly response bias effects. Finally, reanalyses of previous studies of conditional reasoning also showed non-linear ROCs, violating assumptions of traditional analyses. Overall, reasoning research using traditional measures is at risk of drawing incorrect conclusions.