Inhibition of the LH Surge by Restraint Stress in Cyclic Rats: Studies on the Role of GABAA and GABAB Receptors

There is evidence that stress can alter the activity in the brain of gamma-aminobutyricacid (GABA), a neurotransmitter that has been implicated in the regulation of LH secretion. In the present study the role of GABA in the restraint stress-induced inhibition of the LH surge was investigated in the intact cyclic rat. Intracerebroventricular (icv) administration of the GABAA receptor agonist muscimol (0.1, 0.5 or 1 μg) 5 min before the presumed onset of the pro-oestrous LH surge (at 0900 h) caused a dose dependent suppression of the surge. A single dose of the GABAB receptor agonist baclofen (1 μg; icv) injected at 0855 h postponed the onset of the LH surge, and repeated injections at 0855 and 1130 h suppressed the surge. These data indicate that GABA-ergic activity in the brain can inhibit the LH surge in the cyclic rat via GABAA and GABAB receptors. Pro-oestrous rats were subjected to 5 hrs of restraint starting at 0855 h. Pretreatment with the GABAA receptor antagonist bicuculine (1 μg; icv) at 0840, 0940 and 1040 h or pretreatment with the GABAB receptor antagonist phaclofen (10 μg; icv) at 0840 h were ineffective in preventing the restraint-induced inhibition of the LH surge. The results suggest that GABAA and GABAB receptors are not involved in the inhibitory effect of restraint stress on the LH surge.     

Memory processes and experimental continuity

What are the memory processes that produce coherent representations of temporally discontinuous experiences? In this article, we describe the memory process of resonance, a process that provides renewed access to long-term memory information that is relevant to cues in working memory. Our experiments demonstrate c parallel waxing and waning of information as a function of relevance to a current episode, a pattern of accessibility of information that contributes to the achievement of continuity across experiences.     

Empirical Constraints on Computational Theories of Metaphor: Comments on Indurkhya

Empirical analyses have provided some important constraints for computational theories of metaphor. Three such constraints relate to (1) the similar processing time for literal and metaphorical language, (2) the time-limited processing of many metaphors, and (3) the dissociation of metaphor comprehension and appreciation. Indurkhya's (1986, 1987) model is discussed with respect to these issues.     

When Narrative Transportation Narrows Attention: Changes in Attentional Focus During Suspenseful Film Viewing

The construct of narrative transportation captures the psychological processes that occur when people experience an engaging narrative. Attention is an essential component of this construct: People often report feeling that they have focused attention into a narrative world, and disengaged attention from the physical environment. The goal of our research was to test if people’s attention is captured in a dynamic fashion over the course of narrative experiences. To achieve this goal, we used excerpts from narrative films. One way in which filmmakers command viewers’ attention is by generating suspense, which arises when viewers confront potential negative outcomes. In our experiments, we tested the hypothesis that hot spots, moments at which potential negative outcomes are emphasized, will narrow the viewer’s attentional focus compared to cold spots, moments that do not emphasize negative outcomes. We measured attentional tuning through latencies in reaction time to audio probes as participants viewed suspenseful film excerpts. We also administered post-viewing recognition memory tests for still images taken from hot and cold spots. Across three experiments, participants missed more probes and exhibited slower reaction times during suspenseful hot spots than cold spots. These findings provide evidence for changes in attentional tuning as people view film narratives.     

What readers bring to the processing of fictional texts

Research on text processing has generally focused on the types of inferences that all readers draw in common. Our research examines aspects of processing that depend on the particular relation of the reader to the text. Students read fictional stories that contained weak and unsupported assertions and that were set either at their own school or at another school. We expected that they would be prompted to process the story information thoroughly enough to reject the assertions only if they were familiar with the story setting. Consistent with this expectation, the results showed that the away-school story, but not the home-school story, had a significant impact on students’ beliefs. These results support the view that readers must actively construct disbelief when processing fictional information.     

Readers' reality-driven and plot-driven analyses in narrative comprehension

We suggest that when readers experience narratives, their expectations about the likelihood of narrative events are informed by two types of analyses. Reality-driven analyses incorporate real-world constraints involving, for example, time and space; plot-driven analyses incorporate concerns about outcomes that emerge from the plot. We explored the interaction of these two types of analyses in the application of temporal situation models. Participants read stories in which the final episode occurred after a minute time shift (i.e., "A minute later...") or hour time shift (i.e., "An hour later..."). Our experiments assessed participants' judgments and reading times for statements describing the state of events (e.g., the possibility that characters could carry out particular behaviors) following each type of time shift. Experiments 1A and 1B demonstrated that readers are appropriately sensitive to the real concomitants of time shifts. Experiments 2A and 2B demonstrated, even so, that plot-driven preferences modify judgments and reading times away from reality-driven expectations. Our results have implications for the role of the reader in theories of narrative comprehension.     

Flying to Neverland: How readers tacitly judge norms during comprehension

As readers gain experience with specific narrative worlds, they accumulate information that allows them to experience events as normal or unusual within those worlds. In this article, we contrast two accounts for how readers access information about specific narrative worlds to make tacit judgments of normalcy. We conducted two experiments. In Experiment 1, participants read stories about an ordinary character (e.g., a police officer in Boston) or a familiar fantastic character (e.g., Superman). Each story described a realistic event (e.g., the character being killed by bullets) or a fantastic event (e.g., bullets bouncing off the character’s chest). Participants were faster to read events that were consistent with their prior knowledge about the story world. In Experiments 2a and 2b, participants read stories about familiar fantastic characters, unfamiliar fantastic characters (e.g., a Kryptonian named Dev-em), and unfamiliar ordinary characters. In Experiment 2a, participants were equally fast to read about the familiar and unfamiliar fantastic characters experiencing fantastic events, both of which were read faster than the unfamiliar ordinary characters sentences. In Experiment 2b, participants were fastest to read about unfamiliar ordinary characters experiencing realistic events and were equally slow for familiar and unfamiliar fantastic characters. Our experiments provide evidence that readers routinely use inductive reasoning to go beyond their prior knowledge when reading fictional narratives, affecting whether they experience events as normal or unusual.