Abstract
The minimum latency of potentiated startle after delay and trace fear conditioning was investigated. Delay conditioning is hypothesized to be mediated by automatic processes, whereas trace conditioning is hypothesized to involve controlled cognitive processes. In a group receiving delay conditioning, a tone conditioned stimulus (CS) signaled an electric shock unconditioned stimulus (US) presented 1,000 ms after CS onset. In a group receiving trace conditioning, a 200 ms tone CS was followed by an 800 ms gap prior to US presentation. Two control groups received unpaired CS/US presentations. It was hypothesized that fear-potentiated startle should be observed at shorter time intervals after CS onset in the group receiving delay conditioning compared to the group receiving trace conditioning. The results showed increased startle at 100 and 150 ms after CS onset in the group receiving delay conditioning compared to the unpaired group. In the group receiving trace conditioning, increased startle was observed at 1,500 ms after CS onset compared to the unpaired group. This supports the idea that conditioned fear after delay conditioning may be due to automatic processes, whereas trace conditioning is dependent on controlled processes.
References
(2008). Conditioned facilitation of the unconditioned reflex after classical eyeblink conditioning. International Journal of Psychophysiology, 67, 17–22.
(2009). Fear potentiated startle at short intervals following conditioned stimulus onset during delay but not trace conditioning. Psychophysiology, 46, 880–888.
(2004). A comparison of several methods used to quantify prepulse inhibition of eyeblink responding. Psychophysiology, 41, 326–332.
(2004). Timing of fear expression in trace and delay conditioning measured by fear-potentiated startle in rats. Learning & Memory, 11, 205–212.
(2007). Hippocampal activity, but not plasticity, is required for early consolidation of fear conditioning with a short trace interval. European Journal of Neuroscience, 25, 2483–2490.
(1996). Expectancy bias in trait anxiety. Journal of Abnormal Psychology November, 105, 637–647.
(1998). Classical conditioning and brain systems: The role of awareness. Science, 280, 77–81.
(1999). Human eyeblink classical conditioning: Effects of manipulating awareness of the stimulus contingencies. Psychological Science, 10, 14–18.
(2000). The role of the amygdala in conditioned and unconditioned fear and anxiety. In , The amygdala (2nd ed., pp. 213–287). Oxford, UK: Oxford University Press.
(1989). Temporal specificity of fear conditioning: Effects of different conditioned stimulus-unconditioned stimulus intervals on the fear-potentiated startle effect. Journal of Experimental Psychology: Animal Behavior Processes, 15, 295–310.
(2002). The relationship of automatic and controlled processing to prepulse inhibition. Journal of Psychophysiology, 16, 46–55.
(2003). Similar effects of attention directed to acoustic and tactile stimuli on prepulse inhibition of acoustic startle. Scandinavian Journal of Psychology, 44, 361–370.
(1994). Acquisition of contextual Pavlovian fear conditioning is blocked by application of an NMDA receptor antagonist D, L-2-Amino-5-Phosphonovaleric acid to the basolateral amygdala. Behavioral Neuroscience, 108, 210–212.
(1993). Modification of the acoustic startle-reflex eyeblink: A tool for investigating early and late attentional processes. Biological Psychology, 35, 185–200.
(2003). Selective and nonselective attention effects on prepulse inhibition of startle: A comparison of task and no-task protocols. Biological Psychology, 64, 283–296.
(1993). Startle reflex facilitation as a function of classical eyeblink conditioning in humans. Psychophysiology, 30, 581–588.
(1999). Caffeine and prepulse inhibition of the acoustic startle reflex. Psychopharmacology, 147, 322–330.
(1995). Intact delay-eyeblink classical conditioning in amnesia. Behavioral Neuroscience, 109, 819–827.
(1975). More or less startling effects of weak pre-stimulation. Psychophysiology, 12, 238–248.
(1996). Affective learning: Awareness and aversion. Psychophysiology, 33, 698–710.
(2000). Modulation of affective learning: An occasion for evaluative conditioning? Learning and Motivation, 31, 251–271.
(1994). Hypoalgesia in response to sensitization during acute noise stress. Behavioral Neuroscience, 108, 177–185.
(2005). Fear potentiation and fear inhibition in a human fear-potentiated startle paradigm. Biological Psychiatry, 57, 1559–1564.
(2006). Contingency awareness and fear inhibition in a human fear-potentiated startle paradigm. Behavioral Neuroscience, 120, 995–1004.
(1991). In the blink of an eye – real-time stimulus factors in delay and trace conditioning of the rabbits nictitating-membrane response. Quarterly Journal of Experimental Psychology Section B – Comparative and Physiological Psychology, 43, 257–277.
(1999). The neurobiology of startle. Progress in Neurobiology, 59, 107–128.
(1996). Partial disruption of fear conditioning in rats with unilateral amygdala damage: Correspondence with unilateral temporal lobectomy in humans. Behavioral Neuroscience, 110, 991–997.
(1990). Emotion, attention, and the startle reflex. Psychological Review, 97, 377–395.
(1993). Emotional memory systems in the brain. Behavioural Brain Research, 58, 69–79.
(1996). The emotional brain. New York, NY: Simon & Schuster.
(1991). Overlapping projections to the amygdala and striatum from auditory processing areas of the thalamus and cortex. Neuroscience Letters, 134, 139–144.
(2002). The role of awareness in Pavlovian conditioning: Empirical evidence and theoretical implications. Journal of Experimental Psychology: Animal Behavior Processes, 28, 3–26.
(2000). Awareness predicts the magnitude of single-cue trace eyeblink conditioning. Hippocampus, 10, 181–186.
(2001). Single-cue delay eyeblink conditioning is unrelated to awareness. Cognitive, Affective and Behavioral Neuroscience, 1, 192–198.
(1993). Corticoamygdaloid and corticocortical projections of the rat temporal cortex – a phaseolus-vulgaris-leukoagglutinin study. Neuroscience, 57, 697–715.
(1998). Hippocampectomy disrupts auditory trace fear conditioning and contextual fear conditioning in the rat. Hippocampus, 8, 638–646.
(1997). Impaired trace eyeblink conditioning in bilateral, medial-temporal lobe amnesia. Behavioral Neuroscience, 111, 873–882.
(1990). Blocking of acquisition but not expression of conditioned fear-potentiated startle by NMDA antagonists in the amygdala. Nature, 345, 716–718.
(1998). Emotional conditioning to masked stimuli: Expectancies for aversive outcomes following nonrecognized fear-relevant stimuli. Journal of Experimental Psychology: General, 127, 69–82.
(2002). Post-training excitotoxic lesions of the dorsal hippocampus attenuate forward trace, backward trace, and delay fear conditioning in a temporally specific manner. Hippocampus, 12, 495–504.
(2000). Automatic and controlled attentional processes in startle eyeblink modification: Effects of habituation of the prepulse. Psychophysiology, 37, 409–417.
(1980). Preconditioning and excitability of the human orbicularis oculi reflex as a function of state. Electroencephalography and Clinical Neurophysiology, 48, 406–417.
(2005). Acquisition of differential delay eyeblink classical conditioning is independent of awareness. Behavioral Neuroscience, 119, 78–86.
(1986). Hippocampus and trace conditioning of the rabbit’s classically conditioned nictitating membrane response. Behavioral Neuroscience, 100, 729–744.
(2008). In dubio pro defensio: Initial activation of conditioned fear is not cue specific. Behavioral Neuroscience, 122, 685–696.
(1993). Eyeblink classical conditioning in H M: Delay and trace paradigms. Behavioral Neuroscience, 107, 911–925.
