Behavioral responses of 3- to 4-day-old newborns to the odors of various human milk (HM) and formula milk (FM) were examined in paired-choice tests. When both stimuli were nonfamiliar, breast-fed, as well as bottle-fed, infants oriented their head and mouthed more vigorously to HM than to FM. When breast-fed infants were exposed to nonfamiliar HM…

This study demonstrates that non-human primates can categorize the direction of the pitch change of tones in a sequence. Two "Macaca fascicularis" were trained in a positive-reinforcement behavioral paradigm in which they listened to sequences of a variable number of different acoustic items. The training of discriminating pitch direction was…

Learning to discriminate between spatial locations defined by two adjacent arms of a radial maze in the conditioned cue preference paradigm requires two kinds of information: latent spatial learning when the rats explore the maze with no food available, and learning about food availability in two spatial locations when the rats are then confined…

The orbitofrontal cortex (OBFc) has been suggested to code the motivational value of environmental stimuli and to use this information for the flexible guidance of goal-directed behavior. To examine whether information regarding reward prediction is quantitatively represented in the rat OBFc, neural activity was recorded during an olfactory…

Second and sixth grade children solved a series of four-and eight-dimensional discrimination learning problems dictating selection of hypotheses which could be monitored by means of blank trials. Differential effects of stimulus complexity upon the performance of the two age groups are discussed. (GO)

Experiment 1 examined the relationship between dimensional preference and proportion of optional reversal shifts among adults. Experiment 2 examined dimensional preference and shift behaviors using an intradimensional-extradimensional shift paradigm. The results indicate that adults show the same type of behavior previously throught to…

Two experiments examined conditions under which complex discriminative behaviors could be established and maintained by reinforcement given concurrently for performance at related tasks. Results indicated that durable stimulus control of oddity responding could be obtained for two cue dimensions for which oddity responding was never reinforced.…

One of the most robust and reliable learning phenomena documented in the animal learning literature is the enhancement of discriminative performance by differential outcomes. To date, very few studies have focused on this effect in humans. The results obtained in these studies support the potential use of the differential outcomes procedure in…

Recognition memory, defined by novelty preferences, was found to vary over 4 discrimination tasks as a function of length of familiarization for 5-6-month-old infants. (ST)

Elementary school students were tested on a visual search task where letter matching was based on the visual or name characteristics of letters. Visual match lists were searched faster than name match lists by all three grades. (SBT)

This study is an initial investigation of the effects of a fading procedure upon acquisition and transfer of discrimination learning with children younger than 36 months of age. (CS)

Investigated the possibility that evidence of frequency discrimination might be found when the experimental procedures involved the conjugate reinforcement of nonnutritive sucking. (SDH)

Eight autistic children and young adolescents (mean age 12.9 years) were compared to normal chronological age controls. Ss were required to discriminate briefly presented visual stimuli when they were preceded or followed by a visual noise mask and when they were not. The minimum stimulus exposure duration for criterion identification of unmasked…