MEMORY PROCESSES IN DELAYED SPATIAL DISCRIMINATIONS: RESPONSE INTENTIONS OR RESPONSE MEDIATION?

Pigeons were trained on a pair-comparison task in which left versus right choices were reinforced following different sequences of two center-key stimuli. Choice accuracy was higher when retention intervals occurred after the entire sequence than when they separated the two stimuli comprising it, and this effect occurred independently of whether the initial and terminal stimuli came from the same or different dimensions. The initial stimulus from the prior trial was a source of proactive interference only in groups for which the retention interval separated the two sequence stimuli. By contrast, differential delay-interval behavior was observed only in groups for which the retention interval followed presentation of the entire sequence. These results indicate that coding processes in delayed discriminations are influenced by the location of the retention interval, and that response mediation affects retention performances if the reinforced choice can be determined prior to the interval.     

Toward a theory of verbal behavior

This paper is a reply to an accompanying set of six commentaries by Sidman; Hayes and Barnes; Schusterman, Kastak, and Reichmuth; Tonneau and Sokolowski; Lowenkron; and Moerk. Those commentaries were prompted by our article “On the Origins of Naming and Other Symbolic Behavior” (1996), which was, in turn, followed by 26 commentaries and a reply. In the course of the present reply, we further develop the naming account to embrace more complex verbal relations such as same, different, more, and less. We also examine what we see as the lack of conceptual coherence in equivalence theories, including relational frame theory, and the disparities between these accounts and the findings from empirical research.     

Separability of item and person parameters in response time models

This paper discusses two forms of separability of item and person parameters in the context of response time (RT) models. The first is separate sufficiency: the existence of sufficient statistics for the item (person) parameters that do not depend on the person (item) parameters. The second is ranking independence: the likelihood of the item (person) ranking with respect to RTs does not depend on the person (item) parameters. For each form a theorem stating sufficient conditions, is proved. The two forms of separability are shown to include several (special cases of) models from psychometric and biometric literature. Ranking independence imposes no restrictions on the general distribution form, but on its parametrization. An estimation procedure based upon ranks and pseudolikelihood theory is discussed, as well as the relation of ranking independence to the concept of double monotonicity.I am indebted to Wim van der Linden for bringing Thissen's (1983) paper to my notice, and to Martijn Berger, Frans Tan, and the anonymous reviewers for their constructive comments on earlier drafts of this paper.     

Davidson on First-Person Authority

Davidson's explanation of first-person authority in utterance of sentences of the form 'I V that p ' derives first-person authority from the requirements of interpretation of speech. His account is committed to the view that utterance sentences are truth-bearers, that believing that p is a matter of holding true an utterance sentence, and that a speaker's knowledge of what he means gives him knowledge of what belief he expresses by his utterance. These claims are here faulted. His explanation of first-person authority by reference to the requirements of interpretability is committed to the view that all understanding involves interpretation. This is argued to be a misconception of understanding and of speaker's meaning. Davidson's account involves acceptance of the cognitive assumption that normally when a person V s that p , he knows that he does. This assumption is challenged. Throughout, Davidson's conception is compared and contrasted with Wittgenstein's.     

LEADERSHIP TRAINING IN ORGANIZATIONAL JUSTICE TO INCREASE CITIZENSHIP BEHAVIOR WITHIN A LABOR UNION: A REPLICATION

In a replication of a quasi-experiment by Skarlicki and Latham (1996), we investigated the effect of training union leaders ( N = 25) in the administration of organizational justice principles on union members' ( N = 177) perceptions of their leaders' fairness and the members' subsequent citizenship behavior toward their union. Despite the fact that the union members were also shareholders of the company, the results were replicated. Union leader training increased members' perceptions of their leaders' fairness as well as union members' citizenship behavior directed both toward the union as an organization (OCBO) and fellow union members (OCBI). Organizational justice was found to partially mediate the effect of the training on OCBO, but not OCBI.     

Recognition memory ROCs for item and associative information: The contribution of recollection and familiarity

Receiver-operating characteristics (ROCs) were examined in three recognition memory experiments. ROCs for item information (i.e., was this word presented?) were found to be curvilinear. However, ROCs for associative information (i.e., were these two words presented together?) were found to be linear. The results are in agreement with the predictions of a dual-process model that assumes that recognition judgments are -based on familiarity and recollection. Familiarity reflects the assessment of a continuous strength dimension and is well described as a signal detection process, whereas recollection reflects the retrieval of qualitative information about the study episode and behaves like a discrete threshold process. The results showed that memory judgments about items relied on a combination of recollection and familiarity, but that judgments about associations relied primarily on recollection. Further examination of the associative ROCs suggested that subjects were able to recollect that old pairs of items were in the study list, and, under some conditions, that new pairs were not in the study list.     

Inhibitory control over no-longer-relevant information: Adult age differences

Hartman and Hasher (1991) used a garden-path task in which younger and older adults generated the final word for each of a series of high-cloze sentences. Under instructions to remember the final word, the experiment included critical sentences for which the generated word was replaced by a new, to-be-remembered target. Using an implicit priming task, the first experiment replicated a basic finding: Younger adults showed priming only for the target words, whereas older adults showed priming for both the generated and target words. Two experiments explored boundary conditions. One showed that an additional sentence that interpreted the new target word enabled older adults to narrow access to only the target word. The provision of additional time following the introduction of the new target word did not. Specific information, not more time, is required for inefficient inhibitory mechanisms to clear the recent past from memory.     

The Development of the Toddler Behavior Screening Inventory

The purpose of the present study was to develop the Toddler Behavior Screening Inventory (TBSI) for rapidly assessing maternal reports of toddler behavior problems. The TBSI is a 40-item measure intended for use by pediatricians, psychologists, and other child-care professionals. A group of mothers (n = 312) rated the initial 93-item TBSI in terms of behavior frequency and parental perception of the behavior as problematic. Following item elimination, 40 items were retained due to being both frequent and problematic at all toddler age levels. Data were obtained with a new sample of mothers (n = 581) and showed the TBSI to possess good reliability and validity.     

Neurosteroids in the Hippocampus: Neuronal Plasticity and Memory

The hippocampus, which is critically involved in learning and memory processes, is known to be a target for the neuromodulatory actions of steroid hormones produced by the adrenal glands and gonads. Much of the work of B.S. McEwen and collaborators has focused on the role of glucocorticosteroids and estrogen in modulating hippocampal plasticity and functions. In addition to hormones derived from the endocrine glands, cells in the hippocampus may be exposed to locally synthesized neurosteroids, including pregnenolone, dehydroepiandrosterone and their sulfated esters as well as progesterone and its reduced metabolites. In contrast to hormones derived from the circulation, neurosteroids have paracrine and/or autocrine activities. In the hippocampus, they have been shown to have trophic effects on neurons and glial cells and to modulate the activity of a variety of neurotransmitter receptors and ion channels, including type A gamma-aminobutyric acid, N-methyl-D-aspartate and sigma receptors and N- and L-type Ca2+ channels. There is accumulating evidence that some neurosteroids, in particular pregnenolone sulfate, have strong influences on learning and memory processes, most likely by regulating neurotransmission in the hippocampus. However, the hippocampus is not the only target for the mnesic effects of neurosteroids. Associated brain regions, the basal nuclei of the forebrain and the amygdaloid complex, are also involved. Some neurosteroids may thus be beneficial for treating age- or disease-related cognitive impairments.     

Lateralized Changes in Regional Cerebral Blood Flow during Performance of Verbal and Facial Recognition Tasks: Correlations with Performance and “Effort”

Functional neuroimaging has been used to investigate neural substrates of mnemonic processes, and cerebral blood flow (CBF) measures have been sensitive to activation with memory tasks. Studies of memory with two-dimensional¹³³Xenon clearance techniques found that word and face recognition tasks produced contralateral CBF changes in mid-temporal cortical regions. This study replicated the activation paradigm, expanding to the three-dimensional resolution of positron emission tomography (PET). Word and face recognition, and a control baseline task were administered to 19 healthy right-handed volunteers (11 men, 8 women) during successive 10 min PET¹⁵O-water measures of CBF. Quantitative CBF rates were calculated with the arterial input function and the equilibrium model. Redistributions of blood flow were compared across tasks using both absolute and relative (region/whole brain) CBF.Replicating the¹³³Xenon clearance findings, CBF was “appropriately” lateralized during task performance (left–right for words > left–right for faces) in the mid-temporal region. Contrary to predictions, the recognition tasks did not activate expected mesolimbic or prefrontal areas. The task-induced CBF changes also correlated with performance. Bilateral CBF in mid-temporal and parahippocampal gyrus regions of interest correlated with the ability to correctly identify word targets (sensitivity). Left-lateralized CBF in the amygdala and hippocampus correlated with better word sensitivity as well as specificity (ability to correctly reject foils). Complementally, right-lateralized CBF in the parahippocampal gyrus correlated with better face specificity performance. In addition, left-lateralized CBF in the amygdala and right-lateralized CBF in the parahippocampal gyrus and hippocampus correlated with “mental effort” indices (task performance relative to basal ability) for word and face memory tasks, respectively. Thus, whereas this recognition task showed the expected lateralized increase in the mid-temporal region and not in frontal and limbic areas, lateralized activation in some of these areas was associated with better performance. Exploratory analyses on other regions showed lateralized changes in one additional temporal region, the occipital-temporal, and several limbic regions.