Paranoid and teleological thinking give rise to distinct social hallucinations in vision.

Paranoia (believing others intend harm) and excess teleological thinking (ascribing too much purpose) are non-consensual beliefs about agents. Human vision rapidly detects agents and their intentions. Might paranoia and teleology have roots in visual perception? Using displays that evoke the impression that one disc ('wolf') is chasing another ('sheep'), we find that paranoia and teleology involve perceiving chasing when there is none (studies 1 and 2) - errors we characterize as social hallucinations.

The Blindfold Test: Helping to decide whether an effect reflects visual processing or higher-level judgment.

Experimenters often ask subjects to rate displays in terms of high-level visual properties, such as animacy. When do such studies measure subjects' visual impressions, and when do they merely reflect their judgments that certain features should indicate animacy? Here we introduce the 'Blindfold Test' for helping to evaluate the evidence for whether an effect reflects perception or judgment. If the same effect can be obtained not only with visual displays but also by simply describing those displays, then subjects' responses may reflect higher-level reasoning rather than visual processing-and so other evidence is needed in order to support a 'perceptual' interpretation.

Cephalomedullary Nail Lag Screw Migration Following Open Reduction and Internal Fixation of an Intertrochanteric Femur Fracture in a Patient With Body Mass Index of 63.

Hip fractures are prevalent among the elderly population and are correlated with notable morbidity and mortality. Treatment with intramedullary nails has risen in popularity with good results, however complications can occur. We report on a 62-year-old female with a body mass index of 63 kg/m who presents with cephalomedullary nail lag screw migration following an open reduction and internal fixation of an intertrochanteric fracture, which was subsequently converted to a hip hemiarthroplasty after hardware failure of her cephalomedullary nail.

"Visual verbs": Dynamic event types are extracted spontaneously during visual perception.

During visual processing, input that is continuous in space and time is segmented, resulting in the representation of discrete tokens-objects or events. And there has been a great deal of research about how object representations are generalized into types-as when we see an object as an instance of a broader category (e.g.

Spontaneous path tracing in task-irrelevant mazes: Spatial affordances trigger dynamic visual routines.

Given a maze (e.g., in a book of puzzles), you might solve it by drawing out paths with your pencil.

Perceptual (roots of) core knowledge.

Some core knowledge may be rooted in - or even - well-characterized mechanisms of mid-level visual perception and attention. In the decades since it was first proposed, this possibility has inspired (and has been supported by) several discoveries in both infant cognition and adult perception, but it also faces several challenges. To what degree does reflect how babies and ?

Astrocyte coverage of excitatory synapses correlates to measures of synapse structure and function in ferret primary visual cortex.

Most excitatory synapses in the mammalian brain are contacted or ensheathed by astrocyte processes, forming tripartite synapses. Astrocytes are thought to be critical regulators of the structural and functional dynamics of synapses. While the degree of synaptic coverage by astrocytes is known to vary across brain regions and animal species, the reason for and implications of this variability remains unknown.

Perceived gaze dynamics in social interactions can alter (and even reverse) the perceived temporal order of events.

Here's an all-too-familiar scenario: Person A is staring at person B, and then B turns toward A, and A immediately looks away (a phenomenon we call 'gaze deflection'). Beyond perceiving lower-level properties here - such as the timing of the eye/head turns - you can also readily perceive seemingly higher-level social dynamics: A got caught staring, and frantically looked away in embarrassment! It seems natural to assume that such social impressions are based on more fundamental representations of what happened when - but here we show that social gaze dynamics are unexpectedly powerful in that they can actually alter (and even reverse) the perceived temporal order of the underlying events. Across eight experiments, observers misperceived B as turning before A, when in fact they turned simultaneously - and even when B was turning after A.

Mirrored might: A vision for inhibition.

In this issue of Neuron, Znamenskiy et al. unveil functional connection specificity between PV+ inhibitory interneurons and excitatory pyramidal neurons in mouse visual cortex, providing a circuit mechanism for stable amplification of cortical subpopulations.

Astrocyte coverage of excitatory synapses correlates to measures of synapse structure and function in primary visual cortex.

Most excitatory synapses in the mammalian brain are contacted by astrocytes, forming the tripartite synapse. This interface is thought to be critical for glutamate turnover and structural or functional dynamics of synapses. While the degree of synaptic contact of astrocytes is known to vary across brain regions and animal species, the implications of this variability remain unknown.

Efficient Decoding of Large-Scale Neural Population Responses With Gaussian-Process Multiclass Regression.

Neural decoding methods provide a powerful tool for quantifying the information content of neural population codes and the limits imposed by correlations in neural activity. However, standard decoding methods are prone to overfitting and scale poorly to high-dimensional settings. Here, we introduce a novel decoding method to overcome these limitations.

Postsynaptic mitochondria are positioned to support functional diversity of dendritic spines.

Postsynaptic mitochondria are critical for the development, plasticity, and maintenance of synaptic inputs. However, their relationship to synaptic structure and functional activity is unknown. We examined a correlative dataset from ferret visual cortex with in vivo two-photon calcium imaging of dendritic spines during visual stimulation and electron microscopy reconstructions of spine ultrastructure, investigating mitochondrial abundance near functionally and structurally characterized spines.

Visual event boundaries restrict anchoring effects in decision-making.

Research on higher-level thought has revealed many principles of reasoning and decision-making but has rarely made contact with how we perceive the world in the first place. Here we show how a lower-level property of perception-the spontaneous and task-irrelevant segmentation of continuous visual stimulation into discrete events-can restrict one of the most notorious biases in decision-making: numerical anchoring. Subjects walked down a long room in an immersive three dimensional (3D) animation and then made a numerical judgment (e.

What's next?: Time is subjectively dilated not only for 'oddball' events, but also for events immediately after oddballs.

Our experience of time is strikingly plastic: Depending on contextual factors, the same objective duration can seem to fly by or drag on. Perhaps the most direct demonstration of such subjective time dilation is the oddball effect: when seeing identical objects appear one after another, followed by an "oddball" (e.g.

Event segmentation structures temporal experience: Simultaneous dilation and contraction in rhythmic reproductions.

We experience the world in terms of both (continuous) time and (discrete) events, but time seems especially primitive-since we cannot perceive events without an underlying temporal medium. It is all the more intriguing, then, to discover that event segmentation can itself influence how we perceive the passage of time. We demonstrated this using a novel "rhythmic reproduction" task, in which people listened to irregular sequences of musical tones, and then immediately reproduced those rhythmic patterns from memory.

Developmental emergence of sleep rhythms enables long-term memory in .

In adulthood, sleep-wake rhythms are one of the most prominent behaviors under circadian control. However, during early life, sleep is spread across the 24-hour day. The mechanism through which sleep rhythms emerge, and consequent advantage conferred to a juvenile animal, is unknown.

Synaptic weights that correlate with presynaptic selectivity increase decoding performance.

The activity of neurons in the visual cortex is often characterized by tuning curves, which are thought to be shaped by Hebbian plasticity during development and sensory experience. This leads to the prediction that neural circuits should be organized such that neurons with similar functional preference are connected with stronger weights. In support of this idea, previous experimental and theoretical work have provided evidence for a model of the visual cortex characterized by such functional subnetworks.

Postsynaptic mitochondria are positioned to support functional diversity of dendritic spines.

Postsynaptic mitochondria are critical to the development, plasticity, and maintenance of synaptic inputs. However, their relationship to synaptic structure and functional activity is unknown. We examined a correlative dataset from ferret visual cortex with two-photon calcium imaging of dendritic spines during visual stimulation and electron microscopy (EM) reconstructions of spine ultrastructure, investigating mitochondrial abundance near functionally- and structurally-characterized spines.

Here it comes: Active forgetting triggered even just by anticipation of an impending event boundary.

Visual input arrives in a continuous stream, but we often experience the world as a sequence of discrete events - and the boundaries between events have important consequences for our mental lives. Perhaps the best example of this is that memory not only declines as a function of elapsed time, but is also impaired when crossing an event boundary - as when walking through a doorway. (This impairment may be adaptive, as when one "flushes" a cache in a computer program when completing a function.

Seeing Soft Materials Draped Over Objects: A Case Study of Intuitive Physics in Perception, Attention, and Memory.

We typically think of intuitive physics in terms of high-level cognition, but might aspects of physics also be extracted during lower-level visual processing? Might we not only think about physics, but also see it? We explored this using multiple tasks in online adult samples with objects covered by soft materials-as when you see a chair with a blanket draped over it-where you must account for the physical interactions between cloth, gravity, and object. In multiple change-detection experiments ( = 200), observers from an online testing marketplace were better at detecting image changes involving underlying object structure versus those involving only the superficial folds of cloths-even when the latter were more extreme along several dimensions. And in probe-comparison experiments ( = 100), performance was worse when both probes (vs.

Flexible Goals Require that Inflexible Perceptual Systems Produce Veridical Representations: Implications for Realism as Revealed by Evolutionary Simulations.

How veridical is perception? Rather than representing objects as they actually exist in the world, might perception instead represent objects only in terms of the utility they offer to an observer? Previous work employed evolutionary modeling to show that under certain assumptions, natural selection favors such "strict-interface" perceptual systems. This view has fueled considerable debate, but we think that discussions so far have failed to consider the implications of two critical aspects of perception. First, while existing models have explored single utility functions, perception will often serve multiple largely independent goals.

Unraveling Functional Diversity of Cortical Synaptic Architecture Through the Lens of Population Coding.

The synaptic inputs to single cortical neurons exhibit substantial diversity in their sensory-driven activity. What this diversity reflects is unclear, and appears counter-productive in generating selective somatic responses to specific stimuli. One possibility is that this diversity reflects the propagation of information from one neural population to another.

Hallucinating visual structure: Individual differences in 'scaffolded attention'.

Our percepts usually derive their structure from particular cues in the incoming sensory information, but this is not so in the phenomenon of scaffolded attention - where shifting patterns of attention give rise to 'everyday hallucinations' of visual structure even in the absence of sensory cues. When looking at a piece of graph paper, for example, the squares are all identical - yet many people see a shifting array of structured patterns such as lines, crosses, or even block-letters - something that doesn't occur when staring at a blank page. We have informally noted that scaffolded attention is a widely but not universally shared phenomenon - with some people spontaneously experiencing such percepts (even without instruction), others seeing such 'phantom' structures only when actively trying to so, and still others never having such experiences at all.

"Taste typicality" is a foundational and multi-modal dimension of ordinary aesthetic experience.

Aesthetic experience seems both regular and idiosyncratic. On one hand, there are powerful regularities in what we tend to find attractive versus unattractive (e.g.