Concomitant eyeblink and heart rate classical conditioning in young, middle-aged, and elderly human subjects.

Abstract

Pavlovian heart rate (HR) and eyeblink (EB) conditioning were assessed in 4 groups of Ss who differed in age: young = 19-33 years, young middle-aged = 35-48 years, old middle-aged = 50-63 years, and old = 66-78 years. A 100-ms corneal airpuff was the unconditioned stimulus and a 600-ms tone was the conditioned stimulus. A nonassociative control group received explicitly unpaired tone and airpuff presentations. All Ss were studied for 2 100-trial sessions separated by approximately 7 days. An impairment in acquisition of both the EB and HR responses occurred in the old and middle-age Ss, but all age groups showed significantly greater conditioning than did the control group. Slight increases in performance resulted from a 2nd session of training. These findings suggest an age-related impairment in a general associative process.

Discriminative delay Pavlovian eyeblink conditioning in veterans with and without posttraumatic stress disorder

“…Lowered responsivity to predictable aversive external stimulation, regardless of whether it is a conditioned or unconditioned stimulus, may be a characteristic of PTSD in combat veterans. These results are thus similar to the well-known findings that simple delay EB conditioning is lowered in normal elderly subjects (Durkin, Prescott, Furchtgott, Cantor, & Powell, 1993;Woodruff-Pak, Chi, Li, Pak, & Fanelli, 1997), and patients with Chronic Fatigue Syndrome (Servatius et al, 1998) or Major Depressive Disorder (Greer, Trivedi, & Thompson, 2005). The magnitude of the EB UR has been shown to be highly predictive of acquisition of simple delay EB CR, even though failure to acquire the EB CR was not associated with lowering of autonomic arousal (Flaten & Friborg, 2005).…”

Functional anatomy of human eyeblink conditioning determined with regional cerebral glucose metabolism and positron-emission tomography.

“…Although a 500-ms interstimulus interval is not optimal for autonomic conditioning, Durkin et al (49) have shown that significant heart rate conditioning does occur using stimuli and timing parameters similar to those employed in the current experiment. Thus, it is possible that some of the areas that were significantly activated on the paired day relative to the unpaired day represent synaptic activity related to autonomic rather than somatomotor conditioning.…”

Impact of Healthy Aging on Awareness and Fear Conditioning.

“…However, these studies failed to account for age-related changes in overall arousability and habituation across the groups, which were also reported (see Powell, 1999, for further discussion). A more recent study (Durkin et al, 1993) found age-associated impairments in discriminative heart-rate conditioning when nonassociative factors were controlled. Aging studies in nonhuman mammals have shown mixed results.…”