Hormonal influences on photoreceptor damage: the pituitary gland and ovaries

To determine whether the absence of pituitary or ovarian hormones would influence retinal degeneration, female albino rats were either hypophysectomized (HYPEX) or ovariectomized (OVEX) before pubery. Later, they were exposed to continuous light for periods up to 45 days. Retinas evaluated by light microscopic measurements showed damage to the outer nuclear layer (ONL) and photoreceptor layer in both the operated and intact, control rats. However, the degree of damage observed in retinas of HYPEX and OVEX rats was significantly less than that observed in retinas of intact rats exposed to the same lighting conditions. Therefore, hypophysectomy and ovariectomy, which influence the normal development of sexual maturation when performed on immature rats, significantly reduce photoreceptor damage in adult rats exposed to continuous light.     

"Phonotactic influences on short-term memory": Correction.

Reports an error in the original article by S. E. Gathercole et al (Journal of Experimental Psychology: Learning, Memory, & Cognition, 1999[Jan], 25[1], 84–95). On page 87, the mean proportions of correct item recall and standard deviations for the high vocabulary group in Experiment 1B were incorrect in Table 2. The analyses of variance reported for data arising from Experiment 1B were correct. A corrected table is given. (The following abstract of this article originally appeared in record 1998-11970-006.) The impact of phonotactic probabilities on serial recall was investigated in a series of experiments. In Experiments 1A and 1B, 7 and 8 year olds were tested on their serial recall of monosyllabic words and of nonwords varying in phonotactic frequencies. A recall advantage to words over nonwords remained when stimuli were balanced for phonotactic probability, but nonword recall showed superior accuracy for high over low probability nonwords, as in Experiment 2. The nonword frequency effect appears to reflect the frequency of constituent syllables rather than biphones. Both lexicality and high phonotactic frequency led to increased proportions of full over partial recall of the memory stimuli. These findings indicate that decayed memory traces in phonological… (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Becoming famous overnight: Limits on the ability to avoid unconscious influences of the past.

Nonfamous names presented once in an experiment are mistakenly judged as famous 24 hr later. On an immediate test, no such false fame occurs. This phenomenon parallels the sleeper effect found in studies of persuasion. People may escape the unconscious effects of misleading information by recollecting its source, raising the criterion level of familiarity required for judgments of fame, or by changing from familiarity to a more analytic basis for judgment. These strategies place constraints on the likelihood of sleeper effects. We discuss these results as the unconscious use of the past as a tool vs its conscious use as an object of reflection. Conscious recollection of the source of information does not always occur spontaneously when information is used as a tool in judgment. Rather, conscious recollection is a separate act. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Phonotactic influences on short-term memory

The impact of phonotactic probabilities on serial recall was investigated in a series of experiments. In Experiments 1A and 1B, 7 and 8 year olds were tested on their serial recall of monosyllabic words and of nonwords varying in phonotactic frequencies. A recall advantage to words over nonwords remained when stimuli were balanced for phonotactic probability, but nonword recall showed superior accuracy for high over low probability nonwords, as in Experiment 2. The nonword frequency effect appears to reflect the frequency of constituent syllables rather than biphones. Both lexicality and high phonotactic frequency led to increased proportions of full over partial recall of the memory stimuli. These findings indicate that decayed memory traces in phonological short-term memory can be reconstructed using either lexical or phonotactic knowledge.     

Hormonal influences during the ontogeny of maternal behavior in female rats.

Two experiments involving a total of 223 female and 46 male CD rats examined the influence of ovarian hormones on sensitization latencies at different periods in ontogeny and on the olfactory inhibition of maternal behavior, maternal nest building, and pup retrievals from a T-maze extension of the home cage. Ss ovariectomized before puberty failed to show a decline in sensitization latencies when tested 3.5 wks postoperatively; Ss ovariectomized during and after puberty had significantly longer latencies than sham operates when tested 8 or more weeks later. Interrupting olfaction by intranasal ZnSO? reduced latencies. Ovariectomized Ss built less compact maternal nests, and fewer retrieved pups from a –T maze than did sham operates. Estradiol benzoate prior to pup exposure significantly reduced sensitization latencies of ovariectomized Ss, increased the proportion retrieving pups from the maze, and tended to increase maternal nest ratings. Findings indicate that ovarian hormones, primarily estrogen, exert a tonic facilitatory influence on maternal responsiveness, beginning at puberty. (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Aggregation in memory of episodic influences on rule-guided decisions.

The authors confirmed E. Z. Rothkopf and M. L,. Dashen's (1905) finding that specific problem context, such as thematic surface features, forms associative connections with deep problem features and thus speeds particular decisions (particularization). In 5 experiments, using a 3-bit decision task and pre-memorized decision rules, the authors found that the ability of a situational context to reinstate was decreased by its replacement by another modal surface context. Context reinstatement, as measured by decision speed, depended on both global and recent local densities of specific problem features linked in a particular decision. The authors' results are consistent with J. R. Anderson and I. J. Schooler's (1991) needs/odds analysis and suggest a push-down file model for diverse context influences as a mechanism for responding to changing situational demands. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mood dependent memory for events of the personal past.

Previous research on mood dependent memory (MDM) suggests that the more one must rely on internal resources, rather than on external aids, to generate both the target events and the cues required for their retrieval, the more likely is one's memory for these events to be mood dependent. To instantiate this "do-it-yourself" principle, 3 experiments were conducted in which Ss experiencing either a pleasant or an unpleasant mood generated autobiographical events in response to neutral nouns. Subsequently, Ss were tested for event free recall while in the same or the alternative mood state. All 3 studies showed MDM, such that the likelihood of recalling an event generated 2 or 3 days ago was higher when generation and recall moods matched than when they mismatched. Prospects for future research aimed at elucidating and extending these results are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Places and faces: Geographic environment influences the ingroup memory advantage.

The preferential allocation of attention and memory to the ingroup (the ingroup memory advantage) is one of the most replicated effects in the psychological literature. But little is known about what factors may influence such effects. Here the authors investigated a potential influence: category salience as determined by the perceiver’s geographic environment. They did so by studying the ingroup memory advantage in perceptually ambiguous groups for whom perceptual cues do not make group membership immediately salient. Individuals in an environment in which a particular group membership was salient (Mormon and non-Mormon men and women living in Salt Lake City, Utah) showed better memory for faces belonging to their ingroup in an incidental encoding paradigm. Majority group participants in an environment where this group membership was not salient (non-Mormon men and women in the northeastern United States), however, showed no ingroup memory advantage whereas minority group participants (Mormons) in the same environment did. But in the same environment, when differences in group membership were made accessible via an unobtrusive priming task, non-Mormons did show an ingroup memory advantage and Mormons’ memory for ingroup members increased. Environmental context cues therefore influence the ingroup memory advantage for categories that are not intrinsically salient. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Separating conscious and unconscious influences of memory: Measuring recollection.

How can conscious and unconscious influences of memory be measured? In this article, a process-dissociation procedure (L. L. Jacoby, 1991) was used to separate automatic (unconscious) and consciously controlled influences within a task. For recall cued with word stems, automatic influences of memory (1) remained invariant across manipulations of attention that substantially reduced conscious recollection and (2) were highly dependent on perceptual similarity from study to test. Comparisons with results obtained through an indirect test show the advantages of the process-dissociation procedure as a means of measuring unconscious influences. The measure of recollection derived from this procedure is superior to measures gained from classic test theory and signal-detection theory. The process-dissociation procedure combines assumptions from these 2 traditional approaches to measuring memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Aging and prospective memory: Examining the influences of self-initiated retrieval processes.

Past research has frequently failed to find age differences in prospective memory. This article tested the possibility that age differences would be more likely to emerge on a prospective memory task that was high in self-initiated retrieval. In the 1st experiment, participants were asked to perform an action every 10 min (a time-based task presumed to be high in self-initiated retrieval); in the 2nd experiment, participants were asked to perform an action whenever a particular word was presented (an event-based task presumed to be relatively low in self-initiated retrieval). Age differences were found with the time-based task but not with the event-based task. This pattern of age differences was again found in a 3rd experiment in which a new experimental procedure was used and the nature of the prospective memory task was directly varied. Generally, the results suggest that self-initiated retrieval processes are an important component of age-related differences across both retrospective and prospective memory tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An investigation of working memory influences on lexical ambiguity resolution.

The present study employed a combined semantic judgment and lexical decision priming paradigm to examine the impact of working memory on the inhibitory processes of lexical ambiguity resolution. The results indicated that overall, participants activated one meaning of a presented homograph while not priming the alternative meaning. As hypothesized, participants with high working-memory spans exhibited a pattern of priming for congruent conditions and a lack of positive priming for incongruent conditions. In contrast, participants with low working-memory capacity showed priming for both congruent and incongruent conditions, but only for conditions in which the context was related to the dominant meaning of the homograph. The results suggest that people with low working-memory capacity have difficulty inhibiting inappropriate homograph meanings and further demonstrate that these difficulties may vary as a function of context-meaning dominance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The remembrance of times past: Interference in temporal reference memory.

Six experiments examined human performance on a modified temporal generalization task when either 1 or 2 standard durations were encoded. In most conditions, participants were presented with a 1st standard duration (A), then judged whether a number of comparison stimuli had the same duration as A. They were then presented with a 2nd standard (B) and again judged whether other comparison stimuli had the same duration as B. Then, after a delay period of 0-45 s, further comparison stimuli were presented, and participants judged whether those stimuli had the same duration as A, without A being represented. A was either the same length as B or shorter or longer than it, so potential retroactive interference effects of B on A could be examined. After a short delay before retesting of A comparisons, the peak of the temporal generalization gradient shifted toward the shortest of the comparisons when A B. The results suggest that certain combinations of delay and interference might render the memory of A unusable, so that a new standard is constructed on the basis of the remembered relationship between A and B, a kind of false memory for duration. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age-related variation in the influences of aging stereotypes on memory in adulthood.

Adults 24-86 years of age read positive or negative information about aging and memory prior to a memory test. The impact of this information on recall performance varied with age. Performance in the youngest and oldest participants was minimally affected by stereotype activation. Adults in their 60s exhibited weak effects consistent with the operation of stereotype threat, whereas middle-age adults exhibited a contrast effect in memory performance, suggestive of stereotype lift. Beliefs about aging and memory were also affected by stereotypic information, and older adults' changed beliefs were more important in predicting performance than was exposure to stereotype-based information alone. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Interpretation training influences memory for prior interpretations.

Anxiety is associated with memory biases when the initial interpretation of the event is taken into account. This experiment examined whether modification of interpretive bias retroactively affects memory for prior events and their initial interpretation. Before training, participants imagined themselves in emotionally ambiguous scenarios to which they provided endings that often revealed their interpretations. Then they were trained to resolve the ambiguity in other situations in a consistently positive (n = 37) or negative way (n = 38) before they tried to recall the initial scenarios and endings. Results indicated that memory for the endings was imbued with the emotional tone of the training, whereas memory for the scenarios was unaffected. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Memory suppressor genes: inhibitory constraints on the storage of long-term memory

Synaptic plasticity, the ability of neurons to alter the strength of their synaptic connections with activity and experience, is thought to play a critical role in memory storage. Molecular studies of gene expression during long-lasting synaptic plasticity related to memory storage initially focused on the identification of positive regulators. More recent work has revealed that the establishment of long-lasting synaptic plasticity and long-term memory also requires the removal of inhibitory constraints. By analogy to tumor suppressor genes, which restrain cell proliferation, we propose that these inhibitory constraints of memory storage, which restrain synapse growth, be termed memory suppressor genes.     

Glutamatergic influences on the nucleus paragigantocellularis: Contribution to performance in avoidance and spatial memory tasks.

Stimulation of the locus coeruleus (LC) and the subsequent release of norepinephrine contribute to memory consolidation processes. Excitatory input to the LC is derived primarily from neurons in the nucleus paragigantocellularis (PGi). The authors examined the effects of activating the pathway between PGi and the LC on memory. Rats received vehicle or the excitatory amino acid glutamate (25, 50, or 100 nmol/0.5 μl) into PGi after training in an inhibitory avoidance (IA) or delayed matching-to-sample (DMS) task. Rats given the 100-nmol dose had significantly longer retention latencies on a 48-hr IA retention test. Rats treated with the 50- or 100-nmol dose made significantly more correct responses than controls on an 18-hr DMS retention test. Results suggest that encoding and storage of memory for emotional and spatial events may be enhanced by activation of neuronal circuits afferent to the LC. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Genetic influences on memory performance in adulthood: Comparison of Minnesota and Swedish twin data.

Results from 2 twin studies of aging differ concerning the heritability of memory performance in adulthood. Heritability estimates from the Minnesota Twin Study of Adult Development and Aging (MTSADA; D. Finkel & M. McGue, see record 1994-17107-001) are larger than estimates from the Swedish data (N. L. Pedersen, R. Plomin, J. R. Nesselroade, & G. E. McClearn; see record 1993-20499-001). Memory data were available from MTSADA on a sample of 112 monozygotic (MZ) twin pairs and 111 dizygotic (DZ) twin pairs ages 27 to 88 years and from the Swedish study on a sample of 86 MZ and 110 DZ twin pairs who were reared together and were ages 27 to 85 years. Univariate and multivariate behavior genetic analyses were conducted to determine the significance and source of differences in heritability across studies. No significant age differences were found in either study. Study differences were found at the level of specific memory measures, but not at the level of a general memory factor. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Invariance in automatic influences of memory: Toward a user's guide for the process-dissociation procedure.

Three experiments investigated assumptions of the process-dissociation procedure for separating consciously controlled and automatic influences of memory. Conditions that encouraged direct retrieval revealed process dissociations. Manipulating attention during study or manipulating study time affected recollection but left automatic influences of memory relatively invariant. However, paradoxical dissociations were found when conditions encouraged use of a generate-recognize strategy, violating assumptions underlying the estimation procedure. Use of subjective reports to gain estimates produced parallel results. Easily observed correlations are shown to be not useful for testing assumptions underlying the process-dissociation procedure. A multinomial model produced results that agree with those from the process-dissociation approach. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hormonal and reproductive influences and risk of melanoma in women

Ratiometric images of cytoplasmic Ca2+ concentration ([Ca2+]c) in individual cells were recorded simultaneously with a confocal ultraviolet-laser microscope in the Indo-1-loaded islets isolated from mice. After changes in [Ca2+]c in response to glucose or amino acids were recorded, the islet was fixed, permeabilized, and stained by the indirect immunofluorescence method against insulin or glucagon in situ; the individual cells were then identified in the focal plain identical to that used for the [Ca2+]c imaging. Almost all cells identified as insulin-positive (beta-cells) by their distinct immunofluorescence responded to the increase in glucose concentration from 3 to 11 mmol/l with an increase in [Ca2+]c. Major populations of cells (approximately 65%) identified as glucagon-positive (alpha-cells) responded to the addition of arginine (5-10 mmol/l) to 3 mmol/l glucose solution with an increase in [Ca2+]c. About half of the alpha-cells (47.6%) responded to the addition of alanine (5-10 mmol/l) to 3 mmol/l glucose solution with an increase in [Ca2+]c. In contrast, <13% of beta-cells responded to the addition of alanine (5-10 mmol/l) or arginine (5-10 mmol/l) to 3 mol/l glucose with an increase in [Ca2+]c. More than one-fourth of alpha-cells responded with an increase in [Ca2+]c when glucose concentration in perifusion solution was reduced from 11 to 0 mmol/l. These results indicate that [Ca2+]c changes in islet cells stimulated by glucose or amino acid were characteristic of the cell species, at least in the alpha- and beta-cell. This technique provides a useful tool to investigate not only the intracellular signal transduction but also the intercellular signal transmission in the intact islet.