We report data that measure the extent to which the category adaptation aftereffect (Webster 2004) depends on the subject's conscious perception of the adapting stimulus. We describe the results of experiments investigating adaptation of categorical perception boundaries for emotional faces, morphed within identity between neutral and emotive. We manipulated adaptation both with a pre-task adaptation phase and with a prime stimulus, which was either, presented for 500 ms and consciously perceived, or for 22 ms and backward masked, at various prime-test intervals. We analyzed the effects of the prime and of the adaptation phase and their interaction. We replicate the findings of Webster, but our data suggest that the adaptation of the category decision boundary is due to the superimposition of a perceptual and a task factor that also produce separable effects in the reaction time data. We also examine the emergence and decay of adaptation in the reaction time data, which we argue is a better measure of a ch...

Feature integration theory maintains the necessity of attention in binding feature elements to form an accurate perception of a target consisting of conjoined features. Hemispatial neglect provides a unique opportunity to examine this theory in the context of a profound attention deficit. The current experiment examined the effectiveness of a prime consisting of a conjunction that matched a subsequent target (red triangle) vs. a prime consisting of a disjunction of relevant target features (blue triangles and red squares). A psychophysical staircase method (Kaernbach, 1990) was used to vary presentation duration of the prime displays (circular arrays) to produce 75% and 25% detection accuracy. Thresholds to detect a target in the left or neglected visual field were tracked (eye movements were monitored and search items were equidistant from the point of fixation). These thresholds were used as the durations of the primes in the subsequent priming experiment. Primes consisting of either target-related conju...

Manipulation of a large number of neurons is a prime requirement for optogenetic intervention to behavior in mammals with large brain sizes, such as primates. The spatial volume effectively illuminated by a single optical fiber is restricted by attenuat...

Food-related scientific studies often select food items to include based on specific criteria, such as relative levels of fat and sugar content, and use these categorizations for further analyses. While they frequently make intuitive sense, it is unclea...

β-site amyloid precursor protein cleaving enzyme 1 (BACE1) is a prime drug target to inhibit the generation of toxic Aβ. However, it has been known that BACE1 cleaves not only APP but also other substrates including the cell adhesion molecule L1 like pr...

Reflecting on a Successful Year for the SfN Advocacy Community As we begin a new year, we want to highlight the various SfN advocacy programming and the great work SfN advocates were able to accomplish in 2022. SfN hosted its second annual virtual, multi-day Hill Day where 65 participants held 110 meetings representing 27 states and Canada and our 2022 ECPA class participated in SfN’s second annual Congressional Days, hosting 34 meetings.

Ca2+ and CaMKII Contribute to Hyperalgesic Priming Luiz F. Ferrari, Oliver Bogen, and Jon D. Levine (see pages [11002–11011][1]) Inflammation can prime nociceptive afferents, thereby intensifying and prolonging responses to subsequent inflammation even after the initial injury has healed. Such

Distinct neural mechanisms are hypothesized to mediate the separate cognitive processes of selective attention (what information to process) and intention (output selection). Separating the circuitry that determines what information to process from that responsible for the preparation for action has important clinical implications. As such, we subjected 9 healthy control subjects to an event related fMRI paradigm that independently manipulated attentional and intentional cues based on Verfaellie et al (Neuropsychologia 26, 435, 1988). The task consists of trials each with 1 of 3 prime types (an arrow predicting target location, an image of a hand predicting response or a neutral prime), 20% invalid, followed by a target that determines which hand responds. Whole brain EPI was obtained (Siemens 3T) over 5 runs, each 260 s in duration with TR=2.3 s. Data were modeled with the GLM with regressors for combinations of prime, hand, target side and correct/incorrect, convolved with a hemodynamic response. Behavio...

Director John Ngai reflects on the Initiative's unique role

A standing subject, who pulls a handle by flexing the elbow, will force the body forward unless muscles, which oppose the forward movement, are activated. The prime mover in that case is the biceps brachii while the ankle extensors are subject to an anticipatory activation and precedes the biceps activation (Nashner 1982). The mechanisms for this anticipatory activation are not fully understood. Here we investigate the corticospinal activation of the soleus muscle by transcranial magnetic stimulation (TMS) when the muscle is activated as part of an anticipatory response and when the muscle is activated by volition as a prime mover. Seven subjects participated in the experiments. In the anticipatory task subjects were instructed to stand on both legs and hold a handle in their right hand which they were to pull by performing an elbow flexion on an auditory go-signal. During the prime mover task the subjects were told to match by volition the soleus EMG activity observed during the anticipatory response. Alt...