Relational thinking, or the ability to represent the relations between items, is widespread in the animal kingdom. However, humans are unparalleled in their ability to engage in the higher-order relational thinking required for reasoning and other forms of abstract thought. Here we propose that the versatile reasoning skills observed in humans can be traced back to developmental and evolutionary changes in the lateral frontoparietal network (LFPN). We first identify the regions within the LFPN that are most strongly linked to relational thinking, and show that stronger communication between these regions over the course of development supports improvements in relational reasoning. We then explore differences in the LFPN between humans and other primate species that could explain species differences in the capacity for relational reasoning. We conclude that fairly small neuroanatomical changes in specific regions of the LFPN and their connections have led to big ontogenetic and phylogenetic changes in cognition.

Introduction-Cannabinoids produce a spectrum of effects in humans including euphoria, cognitive impairments, psychotomimetic effects, and perceptual alterations. The extent to which dopaminergic systems contribute to the effects of Δ-9-tetrahydrocannabinol (Δ-9-THC) remains unclear. This study evaluated whether pretreatment with a dopamine receptor antagonist altered the effects of Δ-9-THC in humans.

ABSTRACT-Applying knowledge from one context to another is a notoriously difficult problem, both for children and adults, but lies at the heart of educational endeavors. Analogical reasoning is a cognitive underpinning of the ability to notice and draw similarities across contexts. Reasoning by analogy is especially challenging for students, who must transfer in the context-rich and often high-pressure settings of classrooms. In this brief article, we explore how best to facilitate children's analogical reasoning, with the aim of providing practical suggestions for classroom instruction.We first discuss what is known about the development and neurological underpinnings of analogical reasoning, and then review research directly relevant to supporting analogical reasoning in classroom contexts. We conclude with concrete suggestions for educators that may foster their students' spontaneous analogical reasoning and thereby enhance scholastic achievement.A key challenge for students is learning to recognize and learn from opportunities to apply previously learned information to new situations. For example, when teaching students about the atom in school, one approach could be to present an analogy between the solar system and the atom (see Figure 1a). In this example, the solar system represents a domain that is already familiar to students (the source), and the atom represents the domain that students are learning about (the target).

To investigate the effect of altered oestrogen receptor (ER) and ER expression on oestrogen and anti-oestrogen action in breast cancer, we have stably expressed an inducible ER 1 in MCF7 breast cancer cells. Stably expressing clones were isolated and over-expression of ER 1 correlated with increased levels of specific radiolabelled oestradiol (E2) binding. Increased ER 1 did not affect endogenous levels of ER but increased progesterone receptor (PR) levels. Over-expression of ER 1 reduced growth responses to E2 in contrast to little if any effect of over-expression of ER . In oestrogen-replete conditions, over-expression of ER 1 but not ER reduced proliferation. Over-expression of ER 1 did not result in anti-oestrogen resistance but was associated with increased sensitivity to 4-hydroxytamoxifen. Our results suggested that over-expression of ER 1 in the presence of an endogenously expressed ER was associated with tamoxifen sensitivity but may negatively modulate ER -mediated growth. However, not all ER activities were inhibited since endogenous PR expression was increased by both ER and ER 1 over-expression. These data paralleled those seen in some in vivo studies showing a relationship between PR and ER expression as well as ER expression and tamoxifen sensitivity of ER-positive breast cancer patients. These models are relevant and will be useful for dissecting the role of ER 1 expression in ER-positive breast cancer.

Is it possible to induce a mind-set that will affect relational thinking in a subsequent reasoning task involving unrelated materials? We investigated whether evaluating the validity of verbal analogies (Experiment 1a) or generating solutions for them (Experiment 1b) could induce a relational mind-set that would transfer to an unrelated picture-mapping task. The verbal analogies were based on either near or far semantic relations. We found that generating (but not evaluating) solutions for semantically distant analogies increased the proportion of relational mappings on the transfer task, even after we controlled for fluid intelligence and response time. Solving near analogies did not produce transfer. Generation of solutions to far analogies appears to provide a potent method for triggering a mind-set that can enhance relational thinking in a different task.

Analogical reasoning is considered a key driver of cognitive development and is a strong predictor of academic achievement. However, it is difficult for young children, who are prone to focusing on perceptual and semantic similarities among items rather than relational commonalities. For example, in a classic A:B::C:? propositional analogy task, children must inhibit attention towards items that are visually or semantically similar to C, and instead focus on finding a relational match to the A:B pair. Competing theories of reasoning development attribute improvements in children's performance to gains in either executive functioning or semantic knowledge. Here, we sought to identify key drivers of the development of analogical reasoning ability by using eye gaze patterns to infer problem-solving strategies used by six-year-old children and adults. Children had a greater tendency than adults to focus on the immediate task goal and constrain their search based on the C item. However, large individual differences existed within children, and more successful reasoners were able to maintain the broader goal in mind and constrain their search by initially focusing on the A:B pair before turning to C and the response choices. When children adopted this strategy, their attention was drawn more readily to the correct response option. Individual differences in children's reasoning ability were also related to rule-guided behavior but not to semantic knowledge. These findings suggest that both developmental improvements and individual differences in performance are driven by the use of more efficient reasoning strategies regarding which information is prioritized from the start, rather than the ability to disengage from attractive lure items.

Analogical reasoning, or the ability to find correspondences between entities based on shared relationships, supports knowledge acquisition. As such, the development of this ability during childhood is thought to promote learning. Here, we sought to better understand the mechanisms by which analogical reasoning about semantic relations improves over childhood and adolescence (e.g. chalk is to chalkboard as pen is to…?). We hypothesized that age‐related differences would manifest as differences in the brain regions associated with one or more of the following cognitive functions: (1) controlled semantic retrieval, or the ability to retrieve task‐relevant semantic associations; (2) response control, or the ability to override the tendency to respond to a salient distractor; and/or (3) relational integration, or the ability to consider jointly two mental relations. In order to test these hypotheses, we analyzed patterns of fMRI activation during performance of a pictorial propositional analogy task across 95 typically developing children between the ages of 6 and 18 years old. Despite large age‐related differences in task performance, particularly over ages 6–10 but through to around age 14, participants across the whole age range recruited a common network of frontal, parietal and temporal regions. However, activation in a brain region that has been implicated in controlled semantic retrieval – left anterior prefrontal cortex (BA 47/45) – was positively correlated with age, and also with performance after controlling for age. This finding indicates that improved performance over middle childhood and early adolescence on this analogical reasoning task is driven largely by improvements in the ability to selectively retrieve task‐relevant semantic relationships.

The data showed that nicotine had an effect on subjective alcohol effects but did not reverse and actually worsened alcohol-induced deficits in memory.