Subjects were required to attend to a combination of stimulus modality (vision or audition) and location (left or right). Intermodal attention was measured by comparing event-related potentials (ERPs) to visual and auditory stimuli when the modality was relevant or irrelevant, while intramodal (spatial) attention was measured by comparing ERPs to visual and auditory stimuli presented at relevant and irrelevant spatial locations. Intramodal spatial attention was expressed differently in visual and auditory ERPs. When vision was relevant, spatial attention showed a contralateral enhancement of posterior N1 and P2 components and enhancement of parietal P3. When audition was relevant, spatial attention showed a biphasic fronto-central negativity, starting after around 100 ms. The same effects were also present in ERPs to stimuli that were presented in the irrelevant modality. Thus, spatial attention was not completely modality specific. Intermodal attention effects were also expressed differently in vision and audition. Taken together, the obtained ERP patterns of the present study show that stimulus attributes such as modality and location are processed differently in vision and audition.

We have earlier found that voluntary attention to weak auditory stimuli induces inhibition of respiration, heart rate, and electromyographic (EMG) activity of masticatory and lower facial muscles and that these responses lower the auditory threshold for low-frequency sounds. In the current study, we examined whether this inhibitory response pattern also occurs during involuntary orienting to novel, nonsignal sounds. Environmental sounds of low intensity were presented unexpectedly during the performance of a reading task. Orienting responses (ORs) were elicited as indicated by heart rate deceleration and skin conductance responses. Inhibitory respiratory and pericranial EMG responses appeared to be intrinsic components of the OR. Together with the autonomic responses, they habituated when a nonsignal auditory stimulus was repeatedly presented. Our results also suggest that eye and pinna movements occurred toward the sound source. The results of the current study are consistent with the hypothesis of Sokolov (1963) that the primary function of the OR is enhancement of sensory sensitivity.

The effects of a stressful challenge on the processing of emotional words were examined in college students. Stress induction was achieved using a competitive computer task, where the individual either repeatedly lost or won against a confederate. Mood, attention, and cortisol were recorded during the study. There were four findings: (1) Participants in the negative stressor condition were faster to shift attention away from negative words than positive or neutral words; (2) attentional shifts away from negative words were associated with stress-induced mood lowering; (3) participants in the negative stress condition with elevated scores on the Beck Depression Inventory were slow to disengage attention from all stimuli; and (4) elevated depression scores were associated with lower cortisol change from baseline during the experimental phase, and with higher cortisol levels during the recovery phase. These findings point to information-processing strategies as a means to regulate emotion, and to atypical features of cognitive and adrenocortical function that may serve as putative risk markers of depression.

We examined whether responder type groups reflecting patterns of hemodynamic reactivity might also differ in recovery responses. Cardiac output (CO), total peripheral resistance (TPR), systolic and diastolic blood pressure, heart rate, and Heather index were assessed at rest and during speech and cold pressor tasks in young adults. Participants (n = 152) were classified as myocardial, vascular, or mixed-mild responders based on CO and TPR responses to speech presentation. Vascular responders exhibited slower CO and TPR speech recovery than the myocardial and/or mixed-mild groups. Responder type differences in reactivity showed limited task-generalizability. The sustained vascular response pattern of the vascular group is consistent with that seen in hypertension. In light of associations of heightened TPR with markers of disease risk, this suggests potentially negative health implications for vascular responders.

Slow event-related potentials (ERP) were examined in healthy and aphasic subjects in two-stimulus designs comprising a word comprehension and a rhyming task. Aphasics, though selected to perform above chance level, made significantly more errors and responded more slowly than controls, although canonical correlations did not indicate a statistical relationship between performance measures and ERP amplitudes. A discriminant analysis of ERP amplitudes distinguished the groups for the slow wave (SW; 0.5–1.0 s post-S1 onset) in the word comprehension, for the SW and the initial contingent negative variation (iCNV; 1.0–2.0 s post-S1 onset) in the rhyming task. Similarly for both tasks, ERP topography showed left-anterior predominance of the negative SW and iCNV in controls, whereas participants with aphasia showed smaller anterior and larger left-posterior amplitudes. The centroparietal terminal CNV (tCNV; 1 s pre-S2) was smaller in participants with aphasia than in controls, but similar in topography. Results suggest left-anterior activation for those language processes that were presumably provoked in the present tasks, like lexical access, or phonological encoding. The pattern of participants with aphasia may indicate effects of language impairment and recovery, but also consequences of the brain damage.

This study examines the effects of competition and competitiveness on hemodynamics. Cardiovascular activity was measured in 27 men at resting baseline and during a car racing game, which comprised a solo race against time and three races against an experimenter. To assess hematocrit, blood was collected at rest and after the final race. Trait competitiveness was assessed by questionnaire. Competition elicited increases in hematocrit, blood pressure, heart rate, and total peripheral resistance, as well as decreases in preejection period and heart rate variability. The final race was rated as more competitive than the solo race. Compared to intrapersonal solo racing, the final interpersonal race was associated with shorter preejection periods and faster heart rates, markers of beta-adrenergic activation. Although trait competitiveness was not associated with beta-adrenergic activation, variations in state competitiveness were.

This study was designed to investigate early auditory memory and its possible contribution to an auditory processing deficit shown by some children with language impairment. Ten children with language impairment and 10 age-matched controls participated in a series of simultaneous and backward masking tasks. The same backward masking stimulus was then used to elicit a mismatch negativity response. In the behavioral conditions, children in the language impairment group had significantly higher (poorer) signal thresholds than their nonimpaired controls in backward masking, but their thresholds in simultaneous masking were not significantly different. In the mismatch-negativity conditions, latency was prolonged and the amplitude was diminished in the children with language impairment. Taken together, these psychoacoustic and electrophysiological data suggest that in a group of children with language impairment, underlying the nonsensory language disorder, there is a neurophysiological impairment in auditory memory for complex, nonlinguistic sounds.

This study examined the relationship between ERP components elicited by deviant stimuli by disentangling the P300 and Novelty P3 components, using spatiotemporal principal components analysis and a dense electrode array. The three-tone paradigm was used and the pitch attributes of the tones were systematically manipulated so as to map the amplitude of the ERP components on the stimulus context. A comparison was made between the components elicited by events in the three-stimulus, classical oddball, and novelty oddball paradigms. Responses to deviant stimuli consisted of independent and dissociable ERP components in the 400–600-ms time range: A parietal component (P300) that was larger for targets than rare nontargets and was affected by the difficulty of discrimination, a fronto-central component (Novelty P3) that was larger for novel tones and for rare nontargets in the difficult discrimination condition, and an additional anterior negative component responded similarly to all types of deviant stimuli.

ERP researchers use differences in scalp distributions to infer differences in spatial configurations of neuroelectric generators. Since McCarthy and Wood (1985) demonstrated that a spatially fixed current source varying only in strength can yield a significant Condition × Electrode interaction in ANOVA, the recommended approach has been to normalize ERP amplitudes, for example, by vector length, prior to testing for interactions. The assumptions of this procedure are examined and it is shown via simulations that this application of vector scaling is both conceptually flawed and unsound in experimental practice. Because different spatial configurations of neural generators cannot reliably be inferred from different scalp topographies even after amplitude normalization, it is recommended that the procedure no longer be used for this purpose.

Abnormalities during a smooth pursuit eye movement task (SPEM) are common in schizophrenic patients and their relatives. This study assessed various components of SPEM performance in first-degree unaffected relatives of schizophrenic patients. One hundred individuals with schizophrenia, 137 unaffected first-degree relatives, and 69 normal controls completed a 16.7°/s SPEM task. Smooth pursuit gain, catch-up saccades (CUS), large anticipatory saccades, and leading saccades (LS) were identified. Groups were compared with parametric and admixture analyses. Schizophrenic patients performed more poorly than unaffected relatives and normals on gain, CUS, and LS. Unaffected relatives were more frequently impaired than normals only on gain and LS. Relatives of childhood-onset and adult-onset probands had similar impairments. Gain and frequency of leading saccades may be genetic endophenotypes in childhood-onset and adult-onset schizophrenia.

This study investigated cognitive and neural processes involved in gap filling during on-line sentence comprehension. Electroencephalogram (EEG) coherences were used to demonstrate that increases in the synchronization of neural activity in different cortical regions occur during gap filling when load in semantic working memory is high due to semantically unrelated words in the filler-gap interval. Sentences could either require gap filling at a verb or not, and the nouns preceding the verb could be either semantically related or unrelated. In the unrelated but not related condition, coherences in the beta band were larger during verb processing for sentences requiring gap filling compared to sentences not requiring gap filling. The coherence changes involved linkages between frontal and posterior temporal-parietal sites in both hemispheres. These results further indicate that semantic working memory is involved in the process of gap filling.

This report evaluated (a) the temporal stability of hemodynamic responses to three tasks using impedance cardiography, and (b) the influence of aging on stress responses in a multi-ethnic pediatric sample. One hundred children 8 to 10 years old and 49 adolescents 15 to 17 years old were tested at study entry and on average 3 years later. Results showed that the composite task-induced changes in stroke volume (SV), cardiac output (CO), total peripheral resistance (TPR), and pre-ejection period (PEP) were moderately stable across 3 years (rs = .36 to .51), with children showing greater stability in task-induced CO change than did adolescents. However, the magnitude of the participant's stress responses changed over time, varied by task, age group, and gender. These results suggest that hemodynamic responses to stress change with aging during childhood and adolescence and that they can be measured reliably.

An emotion-modulated acoustic startle paradigm for inducing positive and negative affect was used to address pregoal and postgoal affect. Participants played a computerized lottery task in which they chose digits that could match a subsequently displayed, random set of numbers. In the positive conditions, matches led to monetary rewards. In the negative condition, matches led to an aversive noise blast. In three experiments, we found eyeblink startle magnitude was potentiated just prior to feedback concerning reward outcome, suppressed following the feedback that a monetary reward was won, and potentiated when threatened with an aversive noise. When presented with a 0%, 45%, 90%, or 100% chance of winning, higher probabilities suppressed startle response after feedback whereas the 45% trials did not. These data indicate that postgoal positive affect (winning reward) reliably suppressed the startle response whereas pregoal positive affect did not.

Deficits in language comprehension in schizophrenia were examined using event-related potentials (ERPs). Schizophrenic and healthy participants read sentences in which the first clause ended with a homograph, and the second clause started with a target word that was semantically related to the homograph's dominant meaning (e.g., 1. Diving was forbidden from the bridge because the river had rocks in it. or 2. The guests played bridge because the river had rocks in it.). Processing of the targets (e.g., “river”) was expected to be primarily influenced by the preceding overall sentence context (congruent in 1; incongruent in 2) in healthy participants, but to be inappropriately affected by the dominant meaning of homographs (e.g., the “structure” meaning of “bridge”) in sentences like 2 in schizophrenic patients. The N400 ERP component that is known to be sensitive to contextual effects during language processing confirmed these predictions. This showed that language abnormalities in schizophrenia may be related to deficient processing of context-irrelevant semantic representations of words from the discourse.

Increased vagal tone has been associated with treatment success using pharmacological agents and cognitive-behavioral treatment in major depression, but not using electroconvulsive therapy. The present study investigated whether increases in vagal tone would be associated with favorable treatment response with nonpharmacological treatment. At baseline and following treatment, 16 subjects were administered the Hamilton Rating Scale for Depression (HRSD) followed by electrocardiographic recording. Those with little change in vagal tone from before to after treatment showed minimal reduction in HRSD score (−4.8); those with larger vagal tone change showed a large decrease in HRSD score (−14.8). Changes in vagal tone are thus related to favorable treatment response in depression, and do not represent anticholinergic pharmacological effects. Future work manipulating vagal tone might prove informative in teasing apart the causal role of vagal tone and depression.

To explore the stability of immune reactivity across laboratory tasks, we correlated enumerative and functional lymphocyte responses to a speech task and a mental arithmetic task, delivered on the same occasion of testing in 31 healthy undergraduates. Both tasks were associated with an increase in peripheral CD8+ and CD56+ cell populations, and a decrease in proliferative response to phytohemagglutinin (PHA) and ratio of CD4:CD8 cells. Intertask correlations were significant for the magnitude of change in proliferative responses at two different concentrations of PHA, r = 0.76, p < .0001 and r = 0.46, p < .05, and in numbers of circulating CD56+ cells, r = 0.46, p < .005. Concomitant heart rate and systolic blood pressure responses also correlated significantly over the two experimental tasks (heart rate: r = 0.52 and systolic blood pressure: r = 0.58. ps < .0005). These data provide initial evidence that interindividual variability of some cellular immune responses is moderately reproducible across different stimulus conditions, providing further evidence that it may denote a stable individual difference.

Colored grating patterns were presented to 8 participants in a passive oddball condition (standard, 87.5% and deviant, 12.5%, differing in their color). In the corresponding multicolor condition, grating patterns of eight different colors were presented, their probabilities set equal both to each other and to that of the deviant in the oddball task. Compared with the ERP response elicited by the standard stimulus, the deviant response was negatively displaced over posterior areas, the difference wave peaking at 136 ms. A similar negative wave was obtained when the ERP response to the deviant was compared with the ERP elicited by the same stimulus in the multicolor condition. This result rules out stimulus- (color-) specific refractoriness as a major factor in the generation of the deviance-related posterior negativity. The observed posterior negativity can therefore be regarded as a visual analog of the mismatch negativity (vMMN).

To investigate the temporal dynamics of lateralized event-related brain potential (ERP) components elicited during covert shifts of spatial attention, ERPs were recorded in a task where central visual symbolic cues instructed participants to direct attention to their left or right hand in order to detect infrequent tactile targets presented to that hand, and to ignore tactile stimuli presented to the other hand, as well as all randomly intermingled peripheral visual stimuli. In different blocks, the stimulus onset asynchrony (SOA) between cue and target was 300 ms, 700 ms, or 1,100 ms. Anterior and posterior ERP modulations sensitive to the direction of an attentional shift were time-locked to the attentional cue, rather than to the anticipated arrival of a task-relevant stimulus. These components thus appear to reflect central attentional control rather than the anticipatory preparation of sensory areas. In addition, attentional modulations of ERPs to task-irrelevant visual stimuli were found, providing further evidence for crossmodal links in spatial attention between touch and vision.