Cerebral Cortex Communications

The cerebellum has long been considered a late-maturing structure subordinate to neocortical development, therefore its potential role as an early driver of cortical organization remains largely unexplored. Using two large longitudinal neuroimaging cohorts of developing children together with lesion experiments in mice, we show that early cerebellar morphology may drive neocortical maturation in a regionally specific manner. These cross-species findings implicate the cerebellum as a possible regulator of neocortical organization.

Parkinson disease (PD) is characterized by excessive neural synchronization in the 13 to 30 Hz beta band within basal ganglia circuits. Conventional therapies, including dopaminergic medication and deep brain stimulation (DBS), reduce beta synchrony while enhancing lower-frequency theta activity. As an adjunct to these treatments, music and auditory rhythms improve motor function in PD, but the neural mechanisms remain unclear. Here, we recorded local field potentials in the subthalamic nucleus (STN) of patients with PD in the medication off state to test how structured musical elements shape subcortical synchrony. Spectral and neural state-space analyses showed that rhythmic and harmonic components of music produced effects comparable to dopaminergic therapy, suppressing beta-band oscillations while enhancing theta band activity. These effects were strong in the dorsal sensorimotor STN, whereas the ventral limbic STN showed minor modulation. Directional connectivity analysis further revealed that music-induced beta and theta changes were accompanied by increased cortex to STN drive, consistent with top down recruitment of the cortical subthalamic hyperdirect pathway. Notably, harmonic consonance produced network-level modulation comparable to, and in some cases greater than, rhythmic entrainment, extending beyond the established framework of beat based basal ganglia engagement. Together, these findings identify frequency selective, region specific, and stimulus-locked mechanisms by which music reshapes pathological basal ganglia activity in PD, providing direct electrophysiological evidence that auditory stimulation can transiently shift subcortical dynamics toward a medication like state.

Despite the importance of sustaining attention focus throughout a task, sustained attention research demonstrates a rapid decline of task-focus with time-on-task. Separate research body highlights perceptual load as critical determinant of focused attention, showing that increased perceptual load draws more neural energy into task-relevant processing (Bruckmaier et al., 2020) and improves attention focus (Lavie, 2005). However, the effect of perceptual load on the neurophysiological mechanisms underlying time-on-task impact on sustained attention remains unknown. This was the aim of the present study. Participants performed a gradual continuous-performance task, detecting infrequent mountain scenes, among streams of city scenes, under either high or low perceptual load (with or without overlaid salt-and-pepper noise, respectively). EEG was recorded and parameterised into periodic and aperiodic components; the aperiodic 1/f slope linked with excitation-inhibition (E/I) balance: steeper slopes reflecting reduced E/I ratio (Gao et al., 2017). Time-on-task resulted in a wide-spread increase in alpha power, and a steeper 1/f slope in a left temporal-parietal cluster, accompanied by reduced detection sensitivity and increased response variability, as well as increased mind wandering, with reduced thoughts detail. Perceptual load improved task focus, as indexed by reduced mind wandering, but exacerbated the effect of time-on-task on detection sensitivity, and the 1/f slope, which was steeper with time-on-task in a right parieto-occipital cluster with increased load. Overall, the findings suggest that sustained attention decline with time-on-task can be attributed to depletion of neural energy needed for excitatory signalling, which is further drained with increased processing demands in tasks of high perceptual load.

Background Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a poorly understood, debilitating multisystem condition. Converging evidence implicates impaired cellular bioenergetics, neuroinflammation and defective neurovascular coupling that may manifest as "virtual hypoxia" only under physiological stress. Methods We performed a single-session multimodal 3T MRI study combining brain volumetry, arterial spin labelling (ASL) and multivoxel proton magnetic resonance spectroscopy under normoxia and two controlled hypoxic challenges (oxygen saturation 87 {+/-} 3%) in 26 ME/CFS patients and 27 age- and sex-matched healthy controls. Results After intracranial-volume normalization, patients showed a reduced brainstem volume (1.46 0.14 vs. 1.55 {+/-} 0.18 % of eTIV; p = 0.013, FDR-p = 0.039), whereas deep grey matter and whole-brain parenchymal fraction did not differ between groups. Whole-brain cerebral blood flow (CBF) rose under hypoxia in both groups (controls +4.8 {+/-} 13.0%, patients +3.7 {+/-} 11.7%), with greater initial inter-individual variability in patients (patient-to-control variance ratio up to 6.94; FDR-p = 0.001). Thalamic lactate-to-creatine (Lac/tCr) ratios increased with hypoxia in controls (FDR-p = 0.028) but were already elevated at normoxia in patients (0.171 vs. 0.135; FDR-p = 0.021) and did not rise further (FDR-p = 0.38). In exploratory analyses, patients showed exaggerated inverse coupling between thalamic total N-acetylaspartate (tNAA/tCr) and white-matter CBF. Conclusions These findings provide in vivo evidence of impaired neuro-metabolic and vascular adaptive capacity in ME/CFS, supporting the virtual hypoxia hypothesis and highlighting candidate imaging markers for stratification that warrant validation.

How does the auditory system implement spatial selection without a dedicated cortical map for space? One hypothesis holds that auditory spatial attention draws on a supra-modal network including the parietal-occipital cortex; an alternative implicates subcortical structures (e.g., superior colliculus) with no direct recruitment of visual cortex. To adjudicate between these accounts, we used a dichotic listening paradigm and tested whether sustained auditory spatial attention produces the behavioral and neural signatures of visual spatial attention, which would only be expected if auditory attention engages the same cortical mechanisms. Participants listened to two digit streams, spoken by male and female voices, played from left and right speakers. They were instructed to attend to either the left stream, the right stream, or a specific voice gender. A behavioral experiment (N=24) showed higher discrimination accuracy for visual stimuli appearing intermittently at the auditorily attended relative to unattended location. Furthermore, participants gaze was reliably biased towards the attended location. In a second experiment (N=14), we used electrophysiological recordings of frequency-tagged visual evoked potentials to more directly assess early visual processing, and found enhanced visual-cortical responses for stimuli matching the location of the attended auditory stream. In addition, occipital alpha power (8-11 Hz) was reduced over the hemisphere contralateral to the attended sound stream. Together, these effects mirror the hallmarks of visual-spatial attention, suggesting that auditory spatial attention co-opts the architecture of the visual cortex to implement spatial selection, thereby directly enhancing visual processing. Significance statementHuman can effortlessly direct spatial attention to a sounds location in the external world. Yet the auditory system has no dedicated spatial map in the brain, raising a fundamental question: how does auditory spatial attention arise? We show that sustained attention to a sound based on its location produces well-known signatures of visual spatial attention: enhanced visual-perceptual sensitivity, larger early visual-cortical responses, and modulation of occipital alpha-band activity and oculomotor behavior. This converging behavioral and neural evidence demonstrates that auditory spatial attention actively engages and reshapes early visual processing, pointing to a supra-modal attention system shared across the senses.

Cognitive impairment affects up to 80% of patients with drug resistant epilepsy (DRE), yet the basis for this impairment in patients with otherwise comparable disease characteristics remains poorly understood. Prior work has largely focused on identifying focal nodes responsible for cognitive decline, leaving the broader network reorganization associated with cognitive preservation poorly characterized. In this study, we hypothesized that the brain's capacity to reorganize its functional network hubs, rather than the degree of underlying pathology, distinguishes cognitively resilient from cognitively impaired patients. We studied a retrospective cohort of 105 DRE patients and 60 healthy controls who underwent resting-state functional neuroimaging. DRE patients were stratified into epilepsy cognitively neutral (ECN) and epilepsy cognitively impaired (ECI) subgroups based on comprehensive neuropsychological profiling spanning both domain-general and domain-specific levels. The subgroups did not differ in key disease characteristics including epilepsy duration, age of onset, seizure lateralization, and lesion status (p>0.05). We characterized hub organization across the whole brain, canonical functional networks and subcortical levels and summarized each subject's functional reorganization using the hub disruption index. We found that whole brain topology is preserved in both groups whereas disruption concentrates in the salience network and dissociates within subcortical structures with reduced hippocampal node strength in both groups and increased thalamic node strength, with the latter more pronounced with cognitive burden. Inter-network connectivity shifted from focal, selective up-regulation in ECN to diffuse hyperconnectivity in ECI. Critically, the hub disruption index (HDI) for centrality separated the groups where the ECN group showed the greatest redistribution of centrality from canonical hubs towards alternative relay regions whereas ECI demonstrated comparatively little reorganization (ECN vs ECI: d=0.52, p=0.029; Bonferroni corrected). The same pattern held within individual domains, with greater hub reorganization in patients whose language and memory function was preserved. These cross-sectional findings link cognitive impairment in epilepsy to a reduced capacity for adaptive hub reorganization rather than to pathology alone. Because the HDI for centrality is computable at the individual level, it may offer an objective imaging biomarker to complement neuropsychological testing, aid identification of patients at risk for cognitive decline, and inform prognostic counseling and surgical planning in DRE.

Targeted memory reactivation (TMR) during sleep can benefit recently acquired memories, but whether it can also influence memories after an initial period of consolidation remains unclear. Here, we tested whether auditory reactivation during non-rapid eye movement (NREM) sleep could strengthen declarative memories learned 24 h earlier. Twenty-six healthy young adults learned 30 sound word associations and returned the following day for a 90 min nap. During NREM sleep, participants in the Reactivation group received incomplete reminders consisting of the learned sound followed by the first syllable of the associated word, whereas the No-Reactivation group slept under the same conditions without memory related cues. Participants who received reminders showed significantly less forgetting, despite comparable training performance and sleep macroarchitecture. Across NREM sleep, reactivation was associated with greater slow oscillation and delta power, more slow oscillations and fast spindles, and greater slow oscillation spindle cooccurrence. The memory benefit remained significant after adjusting for NREM physiological measures and in sensitivity analyses restricted to overlapping physiological ranges between groups. Cue locked analyses revealed significant responses in the slow oscillation, delta, theta, and fast-spindle ranges, but the magnitude of these responses was not associated with memory change. These findings show that TMR during NREM sleep can benefit declarative memories after a 24 h consolidation interval and suggest that its effects extend beyond the immediate post-learning sleep period.

Developmental dyslexia is a specific, highly prevalent and often debilitating reading and spelling disorder with unknown neurocomputational mechanisms. Here we discovered, in a preregistered functional magnetic resonance imaging study optimized for the subcortical sensory pathway, that dyslexia is characterized by altered predictive coding in left-hemispheric auditory sensory pathway nuclei. The neurocomputational alterations were related to one of the two main dyslexia risk scores, indicating a crucial role for dyslexia pathophysiology.

BackgroundLocomotor adaptation is essential for adjusting walking patterns to complex environments. This study investigated locomotor adaptation deficits in people with Parkinsons disease (PD) and examined oscillatory activity in the globus pallidus internus (GPi) during walking adaptation. We hypothesized that elevated beta-band activity in the GPi is associated with reduced locomotor adaptability in PD. MethodsTwelve PD patients with GPi deep brain stimulation (DBS) (eleven bilateral and one unilateral) were included. Local field potentials (LFPs) were recorded from DBS electrodes during split-belt treadmill walking. Patients were tested in the medication-off, DBS-off state. Locomotor adaptation was measured as the change in step length asymmetry during split-belt walking, with smaller changes indicating greater adaptation deficits. ResultsWe found that GPi high beta (20-30 Hz) and low gamma (30-60 Hz) oscillations were modulated during split-belt walking. Compared to adapters, non-adapters showed decreased movement-related beta suppression during walking. Across participants, beta activity in the GPi contralateral to the fast leg was negatively associated with adaptation magnitude (Spearmans {rho} = -0.65 to -0.75). ConclusionsGPi oscillations are dynamically modulated during locomotor adaptation in PD. Increased beta activity may underlie impaired sensorimotor adaptation during walking. These findings provide novel insight into basal ganglia mechanisms of gait adaptation in PD and suggest that elevated GPi beta activity may serve as a marker of locomotor adaptation deficits.

Sleep is critical for memory consolidation and emotional regulation, yet the respective roles of non-rapid eye movement (NREM) and rapid eye movement (REM) sleep remain unclear. Here, using a within-subject crossover design, we recorded high-density electroencephalography (EEG) across two experimental nights while participants viewed neutral or aversive film clips in a counterbalanced order. Combining with daytime functional localizers establishing neural patterns of aversive vs. neutral emotional processing, multivariate pattern analysis revealed that the reactivation of aversive vs. neutral memory during nocturnal sleep was both stage-dependent and event-specific. In NREM sleep, valence-specific reactivation was time-locked to slow oscillation (SO)-spindle complexes but not to either event alone; in REM sleep, reactivation occurred selectively during phasic REM periods marked by rapid eye movements. Critically, NREM SO-spindle coupling percentage was associated with consolidation of temporal memories; whereas phasic REM reactivation strength was linked to overnight dissipation of negative affect. Our findings provide direct evidence that sleep reprocesses emotional experiences through dissociable stage- and event-specific mechanisms, laying out a framework for future targeted sleep-based interventions.

Language comprehension involves the integration of single words (lexical units) into phrases and sentences (multi-word structures). Previous frequency-tagging studies have found that low-frequency neural responses synchronize to the frequency of multi-word structures. However, it is currently unclear how exactly structural and lexical processes jointly impact these synchronization findings. The present magnetoencephalography experiment implemented the frequency-tagging paradigm in the visual modality with written words to investigate neural synchronization to multi-word sentences varying in internal structure (reversed word orders between verb-initial Spanish and verb-final Basque sentences) and in lexical content (real words and pseudo words). We find converging evidence that neural responses largely synchronize to structural rather than lexical features. This was observed as robust phase synchronization strength to the frequency of sentences containing reversed structures, with certain lexical modulations depending on language-specific structural features. Crucially, we also found shifted phase angle dynamics between the reversed structures of Spanish and Basque sentences independently of word-level lexical characteristics. Together, these findings suggest that neural synchronization to multi-word structures is largely driven by distinct structural features operating via two segregated neural dimensions: frequency coding for the coarser aspects (i.e., timescale/duration) and phase representing the finer-grained aspects (i.e., internal structure) of multi-word structures. Our findings thus advance key insights into the core components of the neural mechanisms supporting language comprehension. HighlightsO_LINeural synchronization to sentences is driven by structural (not lexical) features. C_LIO_LIRobust sentence-frequency synchronization across languages varying in structure. C_LIO_LIPhase angle is selectively sensitive to cross-linguistic structural differences. C_LIO_LILexical modulations depend on language-specific structure. C_LIO_LIStructure synchronization segregates into two dimensions: frequency and phase. C_LI

Sleep is proposed to have a beneficial effect on the consolidation of memories and gist abstraction in adults. For children, gist abstraction is of special relevance to transform new information from social and emotional contexts into stable representations. This study investigated the effect of sleep on emotional and social recognition and gist abstraction on N=34 typically developing children assessed in a sleep and a wake condition. In an emotional memory task, reward-associated stimuli were presented, while a social memory task used face-stimuli to implement social acceptance or rejection from peers. Both paradigms relied on a hidden rule to be abstracted. In general, children were able to remember emotional and social stimuli and to abstract gist information. With respect to sleep, we found a beneficial effect of sleep on the recognition of emotional stimuli but no sleep-dependent enhancement for either social recognition or emotional or social gist abstraction. Overall, our results indicate, that sleep-dependent recognition might depend on the type of memory task. Furthermore, nighttime sleep as compared to daytime wakefulness has no differential influence on gist abstraction in children as assessed in our paradigms, contrasting previous results found in adults.

Past studies using transcranial magnetic stimulation have shown larger motor-evoked potentials when people observe someone lifting a heavy object than when they observe someone lifting a light one. This means that observers may engage their own motor system in proportion to the perceived effort. However, the different responses during the observation of light and heavy objects may have been influenced by predictable trial sequences within blocked presentation, making it unclear whether corticospinal excitability reflects online processing of kinematics or is affected by top-down expectations. In this Registered Report, 57 right-handed participants passively observed videos of a precision grip and lift of heavy and light objects while receiving a single-pulse TMS to the left primary motor cortex during the lift phase of the movement. Motor-evoked potentials were recorded from the right first dorsal interosseous muscle. The study compared two main observation contexts: a predictable trial sequence in which repeated videos of the same lifts were presented in a blocked order, and an unpredictable one in which videos were presented semi-randomly and participants could rely only on kinematic cues to perceive the weight of the lifted object. In both conditions, the same videos of lifts of equivalent-looking heavy and light objects were used and only the order of presentation differed. Contrary to our predictions, in the blocked (predictable) condition, there was no significant difference in MEPs elicited by light and heavy lifts. In the unpredictable condition, participants showed greater corticospinal excitability during the observation of the light lifts compared to the heavy lifts. This suggests that in the absence of predictable information, the corticospinal system was sensitive to the observed kinematics, but contrary to previous findings, its excitability varied inversely with the object weight.

Can grammatical gender in a bilingual's first language shape gender-stereotype processing in a second language? Spanish (L1)-English (L2) bilinguals (n = 28) and English monolinguals (n = 28) completed an event-related potential (ERP) priming task in which English pronouns (SHE/HE) followed gender-stereotyped English nouns, half of which had gender-marked Spanish translation equivalents (e.g., NURSE 'enfermera/o', SURGEON 'cirujana/o'), and half unmarked translation equivalents (e.g., SINGER 'cantante', JANITOR 'conserje'). Both groups showed asymmetric stereotype priming: male pronouns elicited a larger N400 for incongruent than congruent primes, whereas female pronouns elicited a larger P300 for incongruent than congruent primes. Crucially, only bilinguals showed modulation by Spanish grammatical gender marking: the N400 effect for male pronouns was larger for primes with gender-marked than unmarked Spanish translations. These findings provide neural evidence that grammatical gender in a bilingual's first language can influence gender-stereotype processing in a second language, linking cross-linguistic activation to social cognition.

Visual recall is classically thought to depend on reinstatement: areas engaged when encoding a visual input are similarly reactivated when remembering it. Here we investigated if reinstatement might be differently implemented across the diverse category-selective systems of visual cortex. Using fMRI in 25 participants, we assessed possible reinstatement organizations across scene-, face-, and body-selective cortex. We asked whether memory reactivates the same category-selective areas engaged during perception, whether it engages same or distinct vertices, and whether perceptual-mnemonic distinctions were topographically organized. All regions were selectively engaged during both perception and memory, though memory activity was weaker overall. At the vertex-level, most regions--including body-selective LOS, ITG, MTG; face-selective FFA1, FFA2; and scene-selective PPA--showed classic reinstatement, with memory enriched in the most perceptually selective vertices. In contrast, OFA and OPA showed separable perception-and memory-biased vertices. Critically, only scene-selective areas showed topographic distinction: in both PPA and OPA, mnemonic activity was located consistently anterior to perceptual activity, whereas no face-or body-selective areas showed such a distinction. Thus, while all category-selective areas are reactivated during memory, scene-selective cortex topographically separates memory from perception, suggesting different sensory reinstatement implementations across high-level visual cortex, possibly reflecting the distinct computational demands.

Encoding-related pupil responses predict later memory performance, but the neural mechanisms linking these autonomic dynamics to memory formation remain unclear. This study examined whether pupil responses during encoding track activity in the brains memory network and whether they reflect functional interactions between memory-related regions and neural systems involved in pupil control. Participants performed an incidental encoding task involving object stimuli while undergoing simultaneous fMRI and pupillometry; recognition memory was subsequently assessed outside the scanner. Greater pupil constriction during encoding predicted both the strength and quality of later memory. These pupil dynamics correlated with activity in memory-related brain regions, notably the hippocampus and the parahippocampal cortex. Connectivity analyses indicated that encoding-related pupil responses were supported by functional interactions between the hippocampus and the midbrain Edinger-Westphal nucleus, the striatum, and the orbitofrontal cortex. The findings suggest that interactions between memory-related regions and parasympathetic pupil-control systems may modulate encoding efficiency. Together, the results identify encoding-related pupil constriction as a non-invasive marker of memory-network engagement and suggest a hippocampal-midbrain pathway through which autonomic pupil dynamics are coupled with successful memory formation.

Neural speech tracking is stronger for attended speech, yet its common correlation-based readout is scale invariant, so interpreting this effect only as response gain is incomplete. We tested whether attention improves representational fidelity, defined here as scale-invariant agreement between a speech envelope and its neural reconstruction. A leakage-resistant analysis evaluated held-out trials or story parts in three public electroencephalography datasets (52 participants). Fidelity was Fisher-transformed reconstruction-envelope correlation; projection slope quantified scale-dependent gain. In the spontaneous Auditory Attention Switching Dataset, nine odd- numbered participants were used for discovery and nine even-numbered participants for split- sample validation. Fidelity was higher for attended speech in the validation sample and exceeded 5,000 within-trial circular label shifts. The effect replicated under story-part-disjoint validation in KUL and trial-disjoint validation in DTU. A KUL crossover compared the same clean speech sources in attended and ignored states. Across 4,819 isolated spontaneous switches, fidelity did not differ from baseline before the report but shifted toward the newly reported target 0.25-1 s afterward. Passive keypresses altered nonspecific decoder energy. Gain advantages also occurred in all datasets. Selective attention was therefore evident in the scale-invariant preservation of target dynamics, while gain remained a complementary feature.

Working memory (WM) is often assumed to play a stronger role in mental operations than in pure storage. However, much of the evidence comes from tasks using novel stimuli requiring active maintenance. Everyday cognition, in contrast, often involves operating on information retrieved from long-term memory (LTM), which may not always require sustained WM storage. Moreover, prior evidence for enhanced WM involvement relies on univariate measures, which cannot separate procedural demands of operations from representational strength of operation-relevant items. Here, we used EEG to test how WM supports mental operations on LTM. First, participants studied color-position associations. Then, on each trial, a color cue prompted retrieval of its associated position, followed by a novel position. Across blocks, participants either performed a mental operation to compute the positions' spatial midpoint or judged whether the probe matched one of the memory positions. Representations of task type and memory position were assessed using MVPA and inverted encoding models on alpha-band power, respectively. Task type was decoded throughout the trial, reflecting persistent task-set representations. In contrast, LTM position was represented in WM more strongly for integration than recognition early in the retention and operation periods, but these differences were transient. These findings challenge the view that mental operations inherently demand enhanced WM engagement: when information is available in LTM, increased WM involvement is transient, not sustained.

The coordination of sensory processing and working memory (WM) is fundamental to cognition. Spatial organization of sensory processing and WM is known to be broadly distributed across the cortex, but finer-scale organization at the interfaces between these functions remains understudied. Although the notion of sharp parcellations of cortex into distinct functional modules dominates the field, a growing body of works support graded changes in function and anatomy in some cortical zones. Based on this and potential advantages of gradient organizational structure in frontal cortex, we hypothesized that sensory-WM interfaces in the frontal cortex are gradient-like, not boundary-like. We examined twenty bilateral cortical regions that participate in visual/auditory WM tasks. In five frontal cortical regions, group-level WM activation overlapped with sensory drive, but was spatially shifted. We compared subject-level (N=20) boundary and gradient models of change in function. Strong individual-level evidence for sensory-WM gradients was observed in pre-supplementary motor area, ventral premotor cortex, and anterior insula in both modalities and in dorsal premotor cortex for visual WM. Conversely, dorsolateral pre-frontal cortex yielded mixed results, favored distinct WM and sensory regions in the left hemisphere, and gave some evidence for gradients in the right hemisphere. These results provide evidence that sensory and WM regions in frontal cortex are largely not distinct with sharp boundaries at their interfaces but instead bleed into each other to form local rostral-caudal sensory-WM gradients. We speculate these gradients may allow efficient interfacing between sensory and WM representations, and/or fine-grained, task-dependent shifting between bottom-up sensory and top-down influences.

Source and reality monitoring enable individuals to distinguish the origins of remembered information, including whether information was self- or other-generated and whether it was perceived or imagined. Although the dorsolateral prefrontal cortex (dlPFC) and temporoparietal junction (TPJ) have been implicated in these processes, their independent causal contributions remain unclear. We investigated whether focal transcranial direct current stimulation (f-tDCS) of the left dlPFC and left TPJ differentially modulates source and reality monitoring. One hundred participants were randomly assigned to receive anodal or sham stimulation of the left dlPFC or TPJ before completing an episodic memory task manipulating agent (self, experimenter), context (spoken, imagined), and emotional valence (positive, negative). Discrimination sensitivity (d') and response criterion (c) were examined separately. For source monitoring, stimulation interacted with context and cortical region: anodal dlPFC stimulation was associated with a greater spoken-imagined difference in self-experimenter discrimination than sham stimulation, whereas no equivalent context-dependent effect emerged following TPJ stimulation. For reality monitoring, stimulation effects also differed by cortical target, with reduced spoken-imagined discrimination following anodal relative to sham TPJ stimulation and no significant effect of dlPFC stimulation. These effects were not accompanied by corresponding stimulation effects on response criterion. Independent of stimulation, source discrimination was substantially greater for spoken than imagined information, while reality-monitoring sensitivity was enhanced for self-generated relative to experimenter-generated negative information. Together, these findings provide evidence that the dlPFC and TPJ make dissociable contributions to source and reality monitoring, while highlighting the importance of contextual and affective features in determining how the origins of memories are evaluated.