Happier,faster: Developmental changes in the effects of mood and novelty on responses

Positive mood ameliorates several cognitive processes: It can enhance cognitive control, increase flexibility, and promote variety seeking in decision making. These effects of positive mood have been suggested to depend on frontostriatal dopamine, which is also associated with the detection of novelty. This suggests that positive mood could also affect novelty detection. In the present study, children and adults saw either a happy or a neutral movie to induce a positive or neutral mood. After that, they were shown novel and familiar images. On some trials a beep was presented over headphones either at the same time as the image or at a 200-ms stimulus onset asynchrony (SOA), and the task of the participant was to detect these auditory targets. Children were slower in responding than adults. Positive mood, however, speeded responses, especially in children, and induced facilitatory effects of novelty. These effects were consistent with increased arousal. Although effects of novelty were more consistent with an attentional response, in children who had watched a happy movie the novel images evoked a more liberal response criterion, suggestive of increased arousal. This suggests that mood and novelty may affect response behaviour stronger in children than in adults.     

Neuropsychological Impact of Trauma-Related Mental Illnesses: A Systematic Review of Clinically Meaningful Results

Neuropsychology Review - A trauma history is present in approximately 90% of adults in the United States. Comparatively, lifetime post-traumatic stress disorder (PTSD) prevalence...     

Role of nonreinforcement in the fixed-interval performance of pigeons

Fixed-interval (FI) schedules have been used extensively to study timing abilities. In FI schedules, animals typically show higher response rates immediately after nonreinforced (N) cycles rather than reinforced (R) cycles (the reinforcement-omission effect), and they exhibit the highest rate approximately at the time when the reinforcer is scheduled to occur (peak performance). The present experiments were designed to determine the extent to which factors other than timing contribute significantly to these two learning phenomena. Pigeons were trained in an FI 16-sec schedule in which half the cycles were R and half were N. When successive cycles were separated by a 2-sec interval, responding early in the FI interval was higher after an N cycle than after an R cycle. This reinforcement-omission effect was eliminated when the interval between cycles was increased to 12 sec, because of an increase in performance after R cycles. In addition, timing of the 16-sec interval was assessed by interpolating 32-sec test cycles (all N cycles) at two rates—either 1 test cycle every other session, or 25 test cycles per session. Peak performance, presumably indexing the animal’s ability to time the 16-sec interval, emerged only with 25 test cycles per day, but not with 1 test cycle every other day, despite extensive training with the target, 16-sec-long interval. These results suggest that transient demotivation and time-based discrimination contribute significantly to the reinforcement-omission effect and peak performance, respectively.     

Counterfactual thinking in mock juror assessments of negligence: A preliminary investigation

This Research Report presents an initial attempt to apply the theory of counterfactual thinking to study the cognitive processes that underlie judgments of negligence. Subjects reviewed a summary of an appellate case involving a work accident and listed all the ways in which the accident could have been undone (mutated). Participants' evaluations of the defendant's behavior were influenced by the ease of mutation of the negligent act and other mutations of the defendant's behavior, but not by the number of mutations of the plaintiffs conduct. Exploratory path analysis suggested that counterfactual thinking may have its greatest impact not as a direct influence on verdicts and damages, but rather as an indirect influence impacting verdicts through lower level judgments about the normality of the defendant's behavior and the standard of care. The results also suggest that contrary to the law, subjects base their negligence verdicts on assessments of normal care along with due care.     

Do generation and regulation of emotions interact? Examination of their relationships in young adults

Emotions can be generated in response to inherently emotional perceptual properties of a stimulus (‘bottom up’) and in response to cognitive interpretations of an event (‘top down’). Similarly, emotion regulation (ER) strategies may deploy bottom-up or top-down processes, however the specific nature of these processes remains unclear. In this study we sought to replicate and extend previous studies that have investigated the interaction between ER and emotion generation. Specifically, we examined the relationship between both methods of emotion generation and ER in a sample of 75 undergraduate students who completed self-report questionnaires and a behavioral task of ER. We attempted to extend previous research by testing whether the positive effect of cognitive reappraisal on top-down generated emotions was specific to reappraisal or true of multiple ER strategies. Overall there was a main effect of generation such that top-down generated emotion was better regulated by cognitive reappraisal, expressive suppression, and appraisal strategies. We also found a main effect of ER such that cognitive reappraisal was perceived as the most successful ER strategy. We argue that ER is a state-dependent process that includes dynamic cycles between emotion generation and regulation processes. We further discuss expressive suppression as a top-down emotion regulation strategy in the context of our study despite debated literature.     

Conserved: inherited beyond genes / Conservado: heredado más allá de los genes

For more than a century we have discussed the extent to which a trait is innate or acquired, but little has been discussed regarding the mechanisms through which that inheritance takes place. Based on studies by Lorenz and Neo-Darwinism, we have blindly bet on genetics as the mechanism of inheritance. However, evolution considers conserved traits, but this concept lacks a specific inheritance mechanism. We would like to restore the concept of conserved to integrate other inheritance mechanisms. As such, we analyse the inheritance of both genes and the environment, allowing us to fully explore inherited psychopathologies.     

Effect of smoking opportunity on responses to monetary gain and loss in the caudate nucleus

The authors examined the effects of smoking opportunity on neural responses to monetary outcomes in nicotine-deprived cigarette smokers. Participants who were told that they would be able to smoke during the study exhibited smaller responses to monetary gains and losses in the caudate nucleus than did those who anticipated having to wait several hours before having the opportunity to smoke. These findings highlight the importance of investigating the effects of perceived drug use opportunity on motivational processing in addicted populations.     

Common toads (Bufo arenarum) learn to anticipate and avoid hypertonic saline solutions

Toads (Bufo arenarum) were exposed to pairings between immersion in a neutral saline solution (i.e., one that caused no significant variation in fluid balance), followed by immersion in a highly hypertonic saline solution (i.e., one that caused water loss). In Experiment 1, solutions were presented in a Pavlovian conditioning arrangement. A group receiving a single neutral-highly hypertonic pairing per day exhibited a greater conditioned increase in heart rate than groups receiving either the same solutions in an explicitly unpaired fashion, or just the neutral solution. Paired toads also showed a greater ability to compensate for water loss across trials than that of the explicitly unpaired group. Using the same reinforcers and a similar apparatus, Experiment 2 demonstrated that toads learn a one-way avoidance response motivated by immersion in the highly hypertonic solution. Cardiac and avoidance conditioning are elements of an adaptive system for confronting aversive situations involving loss of water balance.     

Mutation at the TrkB PLC{gamma}-docking site affects hippocampal LTP and associative learning in conscious mice

Previous in vitro studies have characterized the electrophysiological properties and molecular events associated with long-term potentiation (LTP), but as yet there are no in vivo data from molecular-level dissection that directly identify LTP as the biological substrate for learning and memory. Understanding whether the molecular pathways required for learning are also those generating LTP when measured directly on the relevant circuit of a learning animal is clearly important, although so far has proved technically difficult. Here, for the first time, we combine highly defined genetic mouse models with behavior and in vivo recordings. We recorded the activity-dependent changes taking place at the CA3-CA1 synapses during the acquisition and extinction of a simple form of an associative learning task in mice carrying point mutations on specific docking sites of TrkB receptors (trkB(SHC), trkB(PLC)). The learning task consisted of a classical eyeblink conditioning using a trace paradigm. The conditioned stimulus (CS) consisted of a tone and was followed by a periorbital electrical shock as an unconditioned stimulus (US). The US started 500 msec after the end of the CS. We show that a single pulse presented to the Schaffer collateral-commissural pathway during the CS-US interval evoked a monosynaptic field excitatory postsynaptic potential (fEPSP) at the CA1 pyramidal cells, with a slope linearly related to learning evolution in controls and trkB(SHC) mutants, but the relationship was impaired in trkB(PLC) mice. These data support a link between the PLCgamma-docking site downstream of TrkB and the activity-dependent synaptic changes evoked at the CA3-CA1 synapses during associative learning in conscious mice, and indicate that TrkB PLCgamma-site-activated molecular pathway(s) underlie both associative learning and LTP triggered at the CA3-CA1 synapse.     

The Influence of Arbitrary Breakpoints on Judgments of Maximum Output

Consumers often wonder about the product's maximum output: the highest rotation speed of a blender or the best printing quality of a printer. We examine how the number of levels (e.g., a blender with 3 vs. 7 speeds) influences judgments of maximum product output. Objectively speaking, the number of levels is no more than a set of breakpoints in an already predetermined continuum from the product's minimum to maximum output. Nevertheless, because of the ubiquitous association between number of breakpoints and quantity in daily life, consumers do not simply view more levels as a signal of greater precision (i.e., giving consumers more control over the possible outputs). They also incorrectly believe that the product has greater power (i.e., a higher maximum output), even when such an inference is in conflict with diagnostic attribute information (e.g., watts). A series of five studies documents the phenomenon, its asymmetric nature, and its boundary conditions. Reliance on the inaccurate “more levels, more power” lay theory weakens when participants consider a reduction rather than an increase in number of levels, and it disappears when the consumer is presented with an explicit relationship between each level and its corresponding output value (e.g., level 4:400 W).