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P J Lang

Publications and source records attributed to P J Lang.

At least 19 recordsLinked to original sources
PubMed1992

Relationship between facial expressiveness and sympathetic activation in emotion: a critical review, with emphasis on modeling underlying mechanisms and individual differences.

Two important questions bearing on personality processes and individual differences are how do facial expressiveness and sympathetic activation vary as a function of the intensity of an emotional stimulus, and what is the functional mechanism underlying facial expressiveness and sympathetic activation in emotion? A formulation is proposed that is based on 2 propositions: (a) All strong emotions result in some degree of activation of the organism (i.e., principle of stimulus dynamism) and (b) there are individual differences in the gain (amplification) operating on the facial expressive and sympathetic response channels (i.e., principle of individual response uniqueness). This formulation organizes much of the existing data on internalizers and externalizers and yields novel predictions regarding the subpopulation labeled as generalizers.

Arousal↗
PubMed1992

Remembering pictures: pleasure and arousal in memory.

Incidental memory performance for pictures that varied along the affective dimensions of pleasantness and arousal was assessed. For both an immediate and delayed (1 year later) free-recall task, only the arousal dimension had a stable effect on memory performance: Pictures rated as highly arousing were remembered better than low-arousal stimuli. This effect was corroborated in a speeded recognition test, in which high-arousal materials encoded earlier in the experiment produced faster reaction times than their low-arousal counterparts. Pleasantness affected reaction time decisions only for pictures not encoded earlier. These results suggest that whereas both the dimensions of pleasantness and arousal are processed at initial encoding, long-term memory performance is mainly affected by arousal.

Adult↗
PubMed1991

Startle and emotion: lateral acoustic probes and the bilateral blink.

The affect-startle effect describes the modulation of the reflexive eyeblink response to a probe startle stimulus as a function of foreground emotional valence. Larger blinks occur during viewing of unpleasant slide foregrounds, relative to positive foregrounds. This effect has been obtained repeatedly using binaural acoustic startle probes. The current study examines this phenomenon for monaural probes administered to the left and right ears in separate blocks. Startle probes were presented during and between exposures to pleasant, neutral, and unpleasant slides, with the ear of presentation counterbalanced across subjects. Left monaural probes produced blink magnitudes that increased linearly from pleasant to unpleasant slide foregrounds, and appeared to be independent of attention or interest. Right monaural probes did not vary with foreground valence. These findings suggest that the startle probe indexes emotional processing that is lateralized in the central nervous system.

Adult↗
PubMed1990

Fear imagery and the startle-probe reflex.

Blink reflexes to acoustic probes, heart rate, and subjective reports were studied during affective memory imagery. Thirty-six undergraduates memorized 6 pairs of neutral and fearful sentences. After learning each pair, they relaxed and listened to a series of uniform tones, one every 6 s. A change in tone pitch (higher or lower) cued recall of one of the two sentences. At the first cue tone, groups (n = 12) were under different instructions: (a) ignore the sentence and relax, (b) silently articulate the sentence, and (c) imagine the sentence content as a personal experience. At the second cue tone, all subjects performed the imagery task. Startle probes (50-ms, 95-dB white noise) were presented unpredictably during relaxation and recall trials. Probe blink reflexes were larger and cardiac rate faster at fear sentence recall than at neutral sentence recall or relaxation. For probe reflexes, this effect was greater for imagery than for nonsemantic recall tasks.

Adult↗
PubMed1990

Startle reflex modification: emotion or attention?

Alternative interpretations of startle probe modulation by a pictorial foreground were tested: Either reflex amplitude varies as a function of modality-determined attention allocation, or, regardless of probe modality, reflex amplitude varies with the emotional valence of the foreground content. Thirty-six subjects viewed a series of 54 slides, divided into two 27-slide blocks. Each block consisted of nine exemplars of three independently rated emotional content categories--pleasant, neutral, and unpleasant. Startle probes, half visual (flashgun) and half acoustic (white noise), were presented unpredictably during and between slide presentations. Eyeblink reflexes, corrugator and orbicularis oculi muscle tension, heart rate, and skin conductance were recorded during a 6-s slide interval. Subjects subsequently rated the slides for emotional valence and arousal, and interest value. Free-viewing times were also recorded. Analysis of reflex response and all ancillary measures supported the hypothesis that the primary determinant of startle modulation was the emotional valence of foreground content.

Arousal↗
PubMed1990

Emotion, attention, and the startle reflex.

This theoretical model of emotion is based on research using the startle-probe methodology. It explains inconsistencies in probe studies of attention and fear conditioning and provides a new approach to emotional perception, imagery, and memory. Emotions are organized biphasically, as appetitive or aversive (defensive). Reflexes with the same valence as an ongoing emotional state are augmented; mismatched reflexes are inhibited. Thus, the startle response (an aversive reflex) is enhanced during a fear state and is diminished in a pleasant emotional context. This affect-startle effect is not determined by general arousal, simple attention, or probe modality. The effect is found when affects are prompted by pictures or memory images, changes appropriately with aversive conditioning, and may be dependent on right-hemisphere processing. Implications for clinical, neurophysiological, and basic research in emotion are outlined.

Arousal↗
PubMed1989

Fear conditioning, meaning, and belongingness: a selective association analysis.

Twenty-three subjects rated the belongingness of pairs of conditionable (photographic slides) and unconditioned (e.g., shock, tone, human scream) stimuli. Forty new subjects were then classically conditioned, using rating-defined high (angry face/scream) and low (landscape/scream) belongingness pairs. Finger-pulse responses to the high-belongingness pairs showed superior acquisition and resistance to extinction. Another 40 subjects were conditioned to compound stimuli: a slide (either landscape or angry face) that was the same over trials, and a yellow or blue background that was the discriminant cue for the unconditioned stimulus (scream). When the angry face (the high-belongingness slide) was the invariant part of the compound, relatively poorer differential pulse-volume and skin-conductance conditioning was observed. Thus, depending on the task, a priori belongingness rendered stimuli selectively conditionable, either enhancing or inhibiting visceral response associations.

Association↗
PubMed1988

Slow brain potentials, imagery and hemispheric differences.

On the basis of Lang's (1979) theory of emotional imagery three experiments were conducted to investigate the relationship between slow cortical potentials (SP) and emotional imagery. According to the assumptions of Lang's theory and our model (Rockstroh et al., 1982) of SP-function imagery ability should be related to a person's capacity to generate and suppress preparatory activity in cortical networks "on demand." In order to test this hypothesis subjects in Experiment I were trained to regulate right- versus left-hemispheric SP-differentiation within an instrumental learning paradigm. Thirty-four subjects were reinforced for achieving maximal SP-differences between electrode locations C3-C4 over a 6 s interval across 120 trials. Success in the SP-regulation task correlated significantly (r = .37) with the capacity for vivid imagery as measured with the Questionnaire for Mental Imagery (QMI). In Experiment II instructions to imagine right- versus left-hand movements were introduced successively over 5 sessions of SP-self-regulation. Imagery clearly modified right- versus left-hand EMG-differentiation but had no influence on cortical SP-differentiation. Experiment III tested the influence of already achieved SP-regulation at the vertex on the perceived vividness of emotional images introduced after the SP-biofeedback training. Again, clear effects of imagery content on autonomic variables (HR, SCR) were found. However, SP-amplitude and SP-polarity had no effect on perceived vividness, arousal or emotional content. It may be concluded from the results of Experiment II and III that SPs either are not the crucial parameter to represent the cortical efferent outflow component of imagery, or that the dual task of SP-self-regulation and imagery prevented covariations to show up. Experiment I, on the other hand, points toward a positive relation of imagery-ability as a trait-variable and brain-self-regulation abilities.

Brain↗
PubMed1976

Psychophysical judgment: electro-cortical and heart rate correlates of accuracy and uncertainty.

The relationship between perceptual accuracy and physiological response amplitude was investigated in an auditory pitch discrimination experiment. Confidence ratings were obtained from all subjects following each trial. The stimulus set consisted of three tones of different frequencies spaced in a manner to provide both easy and difficult discriminations. Heart rate, EEG and vertical eye movement were recorded throughout the experiment. The results of the experiment indicated that the largest evoked cardiac rate response was elicited by the stimulus which produced the fewest errors in judgment; larger auditory evoked potentials, particularly the late positive component (P300), were associated with the 'easy' stimulus; greater cortical negativity was associated with the difficult stimuli. Eye activity was found to covary with judgmental accuracy; cortical slow wave activity was particularly sensitive to the confidence, or 'uncertainty' parameter. A 'decision tree' model was hypothesized to describe the processing mechanism involved in solving the discrimination problem.

Acoustic Stimulation↗