Not so bird-brained: Pigeons show what-where-when memory both as time of day and how long ago.

In an ever-changing world, the ability to track what significant events occur and where and when is beneficial to a variety of animal species. The purpose of the present studies was to assess the presence of this ability to track what-where-when memory in pigeons based both on when during the day the events occurred and how long ago events occurred. In these studies, pigeons were trained to discriminate between two foods that differed in quality (what), making one more "attractive" than the other.

James J. Jenkins (1923-2012).

Presents an obituary for James J. Jenkins. Jim Jenkins, fondly known as "J-cubed," was born on July 29, 1923, in St.

Restoring psychology's role in peptic ulcer.

This paper reviews the history of the transition from the belief that gastrointestinal ulcers are caused primarily by psychological factors to the current state of belief that they are caused primarily by infection and argues that neither is fully accurate. We argue that psychological factors play a significant role as predisposing to vulnerability, modulating of precipitation, and sustaining of gastric ulceration. We review data that challenge the assumption of a simple infectious disease model and adduce recent preclinical data that confirm the predisposing, modulatory, and sustaining roles for psychological factors.

Delay activity in avian prefrontal cortex--sample code or reward code?

In the current study, we examined whether delay activity in the avian equivalent of the prefrontal cortex (PFC) represents a neural correlate of a to-be-remembered sample stimulus or an upcoming reward. Birds were trained on a directed forgetting paradigm in which sample stimuli (red and white) were either followed by a cue to remember (high-frequency tone) or a cue to forget (low-frequency tone). The task also incorporated a differential outcomes procedure in which a correct response on the memory test following a red (remember) sample was rewarded with food, but correct responses on the memory test following the white (remember) sample were not.

Neural correlates of cue-unique outcome expectations under differential outcomes training: an fMRI study.

In conditional discriminative choice learning, one learns the relations between discriminative/cue stimuli, associated choices, and their outcomes. When each correct cue-choice occurrence is followed by a cue-unique trial outcome (differential outcomes, DO, procedure), learning is faster and more accurate than when all correct cue-choice occurrences are followed by a common outcome (CO procedure)--differential outcomes effect (DOE). Superior DO performance is theorized to be mediated by the additional learning of cue-unique outcome expectations that "enrich" the prospective code available over the delay between cue and choice.

Improving conditional discrimination learning and memory in five-year-old children: differential outcomes effect using different types of reinforcement.

Previous studies have demonstrated that discriminative learning is facilitated when a particular outcome is associated with each relation to be learned. When this training procedure is applied (the differential outcomes procedure; DOP), learning is faster and better than when the typical common outcomes procedure or nondifferential outcomes (NDO) is used. Our primary purpose in the two experiments reported here was to assess the potential advantage of DOP in 5-year-old children using three different strategies of reinforcement in which (a) children received a reinforcer following a correct choice (" + "), (b) children lost a reinforcer following an incorrect choice (" - "), or (c) children received a reinforcer following a correct choice and lost one following an incorrect choice (" + / - ").

Lipopolysaccharide-induced immune activation impairs attention but has little effect on short-term working memory.

Cytokine-induced CNS inflammation has been theorized to contribute to cognitive dysfunction in sickness and neurodegenerative disease. We investigated the effects of systemic endotoxin-induced acute immune activation and inflammation on working memory and attention functions in pigeons assessed through two variations of an operant symbolic matching-to-sample (SMTS) task, employing doses of lipopolysaccharide (LPS) sufficient to induce fever. LPS produced moderate impairments in comparison to saline on the SMTS task designed to measure visual vigilance and attention, but the impairments were not as marked as those produced by chlordiazepoxide (CDP) which is known to disrupt attention.

Enhancing challenged students' recognition of mathematical relations through differential outcomes training.

Previous studies have reported that the differential outcomes procedure enhances learning and memory in special populations with cognitive deficits (see Goeters, Blakely, & Poling, 1992, for a review). In the present study we extend these findings to healthy adults who were asked to discriminate between the symbols " > " and " < " in mathematical statements. In Experiment 1, the performance of participants who showed difficulties in discriminating between these symbols was better (shorter response times) for the differential outcomes condition than for the nondifferential outcomes condition.

Associatively activated representations of food events resemble food outcome expectancies more closely than they resemble food-based memories.

When Pavlovian stimuli activate representations of food, do these representations resemble memories of food consumed in the recent past or expectancies of food that is imminent? In Experiments 1A and 1B, this question was addressed by training pigeons on a symbolic matching-to-sample task involving different grains as memory cues or as expectancy cues for correct choices. Autoshaping trials involving these same grains were interspersed among matching-to-sample trials, as were test trials involving the substitution of autoshaping stimuli for cues in the matching-to-sample task. Control over choices transferred to autoshaping stimuli in both experiments, suggesting that associatively activated representations of food resemble both memories and expectancies.

Recommended housing conditions and test procedures can interact to obscure a significant experimental effect.

Routine animal husbandry variables, such as group housing of mice and the order of testing of cage-mates, are currently viewed to be essentially neutral with respect to the outcome of most, if not all, animal-based experiments, including those that utilize behavioral measurements. During the course of experiments that have utilized the elevated plus-maze to examine the ability of a bacterial challenge of mice to induce anxiety-like behavior, due to the activation of various cytokine pathways, we followed the recommendation of laboratory animal care staff to house the mice in pairs. Whenwe testedthe members of the pairs successively, it was found, for the first experimental set, that the behavior that reflects anxiety (time in closed arms) of the first-tested animal differed from that of the second-tested animal for both the experimental and the control animals and, critically, that these changes were in the opposite directions for the controls and the experimental animals, thus obscuring the effect of the experimental manipulation.

An acute stressor enhances sensitivity to a chemical irritant and increases 51CrEDTA permeability of the colon in adult rats.

We investigated the effect of prior acute stress on colonic permeability induced by a chemical irritant known to induce symptoms similar to inflammatory bowel disease in rodents. Adult male rats (n = 12) were stressed by a single session of ten unpredictable, uncontrollable foot shocks, and half were home cage controls (n = 12). Twenty-nine days later, half of each treatment group was exposed to 4% DSS (dextran sulphate sodium) solution in their drinking water for 48 hours while half received pure water over two periods separated by 17 days.

Sensitization and conditioning as contributors to gastrointestinal vulnerability.

Electric shocks are stressful and if signalled can result in Pavlovian conditioning of the stress response. Stress arising from such shocks or conditioned psychological "threat" influences vulnerability to gastrointestinal disorders. Reviewed are our studies with rats showing that unconditioned stress experiences sensitize the glandular portion of the stomach to later restraint-in-water induced erosions, as an animal model of ulcer disease.

Effects of lipopolysaccharide on consolidation of partial learning in the Y-maze.

Research on consolidation of long-term memory suggests that acute immune system activation induced by endotoxin lipopolysaccharide (LPS) may disrupt consolidation of newly acquired learning. Adult male Sprague-Dawley rats were trained to perform a simple Y-maze task and were immediately afterwards administered LPS (15 microg/kg) or saline. After a seven-day interval, subjects were returned to the Y-maze and were retrained to criterion.

A comparison of spaced retrieval to other schedules of practice for people with dementia.

Spaced retrieval training uses a schedule of practice trials distributed according to a learner's performance. The authors compared spaced retrieval to four alternative schedules of practice to determine whether it is more effective than other schedules for people with dementia. Participants practiced (a) pill names or (b) nonverbal sequences.

Trauma and resulting sensitization effects are modulated by psychological factors.

Traumas have both immediate consequences and proactive consequences. Examples include learned helplessness, HPA-axis responsivity, gastrointestinal vulnerability to ulcer, and other correlates of anxiety disorders. Both immediate and proactive consequences may be modulated by behavioral and cognitive evolutionary evolved adaption processes, among which are forms of learning that enable 'coping'.

The role of Pavlovian cues in alcohol seeking in dependent and nondependent rats.

Objective: Recent treatment approaches to substance use disorders have focused on reducing drug use by modifying drug-seeking behaviors in response to drug-associated cues. Understanding the effect of alcohol-related stimuli on alcohol-seeking responses is therefore of interest in the study of alcoholism. The present study examined the impact of ethanol- (ETOH) associated cues on selective ETOH-seeking behavior, using a Pavlovian-instrumental transfer design in groups of alcohol-dependent and nondependent rats.

Differential outcomes effect in children and adults with down syndrome.

In previous studies, researchers have demonstrated that learning of symbolic relations is facilitated when a particular outcome is associated with each relation to be learned. In the present study, we extend this differential outcomes procedure to children and adults with Down syndrome who had to learn a symbolic conditional discrimination task. Participants showed a better terminal accuracy and a faster learning of the task when the alternative correct responses were each followed by unique different outcomes than when nondifferential outcomes were arranged.

On learned helplessness.

"Learned helplessness" and its Pavlovian analog, learned irrelevance, are phenomena thought integral to understanding depression, PTSD, psychosomatic vulnerability, and a variety of diseases and immune disorders. The origin and development of research on learned helplessness is briefly overviewed with attention to the reasons for the controversy that surrounds the study of learned helplessness and derived physiological, psychological, and behavioral phenomena. The need to remedy past focus on American research and English language journals in this area is noted.

Sensitization, conditioning, and learning: can they help us understand somatization and disability?

This paper reviews those features of non-associative and associative forms of learning, as elaborated in the experimental literature, that might contribute to experienced and reported discomfort in the workplace. Emphasis is given to sensitization, while noting that some models of habituation (e.g.

Inhibition of return in aging and Alzheimer's disease: performance as a function of task demands and stimulus timing.

Inhibition of return (IOR) is a phenomenon of spatial attention that biases attention toward novel events in the environment. Recent evidence suggests that the magnitude and timing of IOR varies as a function of task conditions (e.g.

Conditional choice-unique outcomes establish expectancies that mediate choice behavior.

Conditional discriminative choice tasks can be arranged such that all correct choices yield the same reinforcer or such that each type of correct choice has its own unique reinforcer. The former is the traditional "Common Outcomes" Procedure; the latter is the "Differential Outcomes" Procedure. Use of this Differential Outcomes Procedure facilitates the rate of learning, increases the asymptotic level of performance, and enhances working-memory based performances in both animals and humans.

Ibuprofen effects on Alzheimer pathology and open field activity in APPsw transgenic mice.

We previously showed the non-steroidal anti-inflammatory drug (NSAID) ibuprofen suppresses inflammation and amyloid in the APPsw (Tg2576) Tg2576 transgenic mouse. The mechanism for these effects and the impact on behavior are unknown. We now show ibuprofen's effects were not mediated by alterations in amyloid precursor protein (APP) expression or oxidative damage (carbonyls).

Performance more than working memory disrupted by acute systemic inflammation in rats in appetitive tasks.

Evidence from molecular biology, epidemiology, behavioral pharmacology, and clinical science support the conclusion that brain inflammation contributes to the pathogenesis of cognitive symptoms in Alzheimer's disease (AD) and other neuropsychological disorders. Three different tests were conducted to determine whether the acute inflammatory response induced by systemic lipopolysaccharide (LPS) treatment is accompanied by a selective disruption of working memory functioning in rats. Doses of LPS sufficient to induce a thermoregulatory response were administered intraperitoneally and their effects on behavioral measures of symbolic working memory, spatial learning, and spatial memory consolidation, were assessed.

Anxiety and helplessness in the face of stress predisposes, precipitates, and sustains gastric ulceration.

When an organism is subjected to stress, gastric ulcers or ulcerations commonly develop but the vulnerability to and amount of pathology induced varies considerably between individuals. The role of psychological factors in determining the occurrence and severity of these ulcerations is amply demonstrated in the studies reviewed here. The present paper (a) gives a brief history of the search for the causes of gastric ulcer, (b) provides a review of our own research which reveals that vulnerability to gastric ulceration is modulated by psychologically meaningful experiences, and (c) offers a multifactorial perspective on the causes of gastric ulceration and the future of research on it.