Biomedical subjects

J Mirak

Publications and source records attributed to J Mirak.

3 recordsLinked to original sources

PubMed1998

Five-year retention of the classically conditioned eyeblink response in young adult, middle-aged, and older humans.

Human participants who 5 years earlier participated in studies of acquisition of the classically conditioned eyeblink response to a tone conditioned stimulus (CS) and an air puff unconditioned stimulus (UCS) returned to the laboratory to test for retention of the conditioned response (CR). Retention consisted of 20 tone CS-alone presentations. Young adult participants (23-31 years of age at the time of retention testing) showed good retention of the CR (45%), middle-aged participants (45-52 years) showed reduced retention (28%), and older participants (69-78 years) showed little evidence of retention (< 5%). Retention testing was followed by reacquisition of the CR in which the CS and the UCS were again paired. The ability to reacquire the CR also showed a decline with age. The data suggest that the CR can be retained over long intervals and that the degree of retention is age dependent.

Adolescent↗

PubMed1997

Normal language acquisition.

Long before they start talking, children are skilled at using eye contact, facial expression, and nonverbal gestures to communicate with other people. They also are able to discriminate speech sounds from an early age. Vocabulary learning builds on the child's knowledge about objects, actions, locations, properties, and stages gained as a result of sensorimotor development. Early word combinations allow children to express semantic relationships between these various referents. During the period from 2 to 4 years of age, children move from expressing their ideas in simple telegraphic speech to being able to ask questions, use negation, talk about past and future events, and describe complicated situations using sentences constructed according to complex grammatical rules.

Child↗

PubMed1993

Disruption of human eyeblink conditioning after central cholinergic blockade with scopolamine.

Human (Homo sapiens) volunteers (N = 72) received saline, a low dose of oral scopolamine (0.6 mg), a high dose of oral scopolamine (1.2 mg), or a peripheral analogue (glycopyrrolate). They then underwent classical conditioning of the eyeblink response to a tone conditioned stimulus (CS) and a corneal airpuff unconditioned stimulus (UCS) in a delay conditioning paradigm. There was a dose-related decline in acquisition of the conditioned response. These drug-induced conditioning deficits were similar to those previously reported in rabbit eyeblink conditioning and could not be attributed to such nonassociative factors as changes in auditory thresholds to the tone CS, magnitude of reflexive blinks to the airpuff UCS, or to changes in spontaneous blink rates.

Administration, Oral↗