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William J Friedman

Publications and source records attributed to William J Friedman.

9 recordsLinked to original sources
PubMed2006

The mental representation of countries.

Three studies were conducted to describe adults' knowledge of the countries of the world. Undergraduates from a selective liberal arts college recognised nearly two-thirds of nations, and about one-third were produced in a free-recall task. The use of information related to countries' locations was an important determinant of order of recall. Contiguity in free-recall output, responses in a free-association task, and the prediction of recall from recognition also provided evidence of other relations between countries, including semantic and phonetic links and membership in groups of countries. The number of times a country was mentioned in the news was a consistent predictor of recognition and recall. The relative prosperity, population density, and geographic area of countries also influenced recall.

Adult↗
PubMed2004

The effects of aging on location-based and distance-based processes in memory for time.

Retrieving when an event occurred may depend on an estimation of the age of the event (distance-based processes) or on strategic reconstruction processes based on contextual information associated with the event (location-based processes). Young and older participants performed a list discrimination task that has been designed to dissociate the contribution of both types of processes. An adapted Remember/Know/Guess procedure [Can. J. Exp. Psychol. 50 (1996) 114] was developed to evaluate the processes used by the participants to recognize the stimuli and retrieve their list of occurrence. The results showed that aging disrupts location-based processes more than distance-based processes. In addition, a limitation of speed of processing and working-memory capacities was the main predictor of age-related differences on location-based processes, whereas working-memory capacities mediated partly age differences on distance-based processes.

Adolescent↗
PubMed2004

ERP old/new effects at different retention intervals in recency discrimination tasks.

Recognition memory studies have suggested that event-related brain potentials (ERPs) may tap into several different memory processes. In particular, two ERP components have been hypothesized as related to familiarity (FN400 old/new effect, 300-500 ms, anterior) and recollection processes (parietal old/new effect, 400-800 ms, posterior). The functional significance of the FN400 old/new effect is uncertain because similar old/new differences have been shown to disappear at moderately long retention intervals. The present study investigated the effects of retention interval (34 min, 39 min, or 1 day) on the FN400 and parietal old/new effects in two different recency discrimination tasks. The results suggest that the FN400 old/new effect can be maintained across 1-day retention intervals, so it may index brain processes capable of contributing to long-term memory.

Analysis of Variance↗
PubMed2003

Differentiating location- and distance-based processes in memory for time: an ERP study.

Memory for the time of events may benefit from reconstructive, location-based, and distance-based processes, but these processes are difficult to dissociate with behavioral methods. Neuropsychological research has emphasized the contribution of prefrontal brain mechanisms to memory for time but has not clearly differentiated location- from distance-based processing. The present experiment recorded event-related brain potentials (ERPs) while subjects completed two different temporal memory tests, designed to emphasize either location- or distance-based processing. The subjects' reports of location-based versus distance-based strategies and the reaction time pattern validated our experimental manipulation. Late (800-1,800 msec) frontal ERP effects were related to location-based processing. The results provide support for a two-process theory of memory for time and suggest that frontal memory mechanisms are specifically related to reconstructive, location-based processing.

Distance Perception↗
PubMed2002

Arrows of time in infancy: the representation of temporal-causal invariances.

Many transformations that take place over time can only occur in one temporal direction, and adults are highly sensitive to the differences between forward and backward presentations of such events. In seven experiments using two selective-looking paradigms, 4- and 8-month-olds were shown forward and backward videotapes of events involving the effects of gravity on liquids and solid objects and of the separation of whole objects into pieces. Four-month-olds showed a significant preference for the forward version of liquid pouring from a beaker to a glass. Eight-month-olds looked longer at the forward versions of this and four other gravity-related events but showed no directional preferences for the separation events. Several experiments indicate that longer looking at the forward versions of the gravity stimuli is not a product of attraction to specific perceptual features of the stimuli. A model based on the development of representations of types of events is presented and evaluated.

Analysis of Variance↗
PubMedDate not supplied

Arrows of time in early childhood.

Three studies with 149 children were conducted to provide information about development of the perception of temporally unidirectional transformations, such as dropping blocks or breaking a cookie. Children 3.5 through 6.5 years of age compared forward and backward videotapes of events or made individual judgments of what would happen if the actions were attempted. Even children 3.5 to 4.5 years of age recognized the anomaly of backward versions of gravity and separation events. In addition, relatively few children predicted impossible transformations in the prediction task. The results show that young children, like adults, are sensitive to the unidirectional nature of varied transformations.

Child Development↗
PubMedDate not supplied

Intentionality as measured in the persistence and elaboration of communication by chimpanzees (Pan troglodytes).

In human infancy, 2 criteria for intentional communication are (a) persistence in and (b) elaboration of communication when initial attempts to communicate fail. Twenty-nine chimpanzees (Pan troglodytes) were presented with both desirable (a banana) and undesirable food (commercial primate chow). Three conditions were administered: (a) the banana was delivered (successful communication), (b) half of the banana was delivered (partially successful communication), and (c) the chow was delivered (failed communication). The chimpanzees exhibited persistence in and elaboration of their communication in every condition except when the banana was delivered. Thus, their communication was about a specific item, demonstrating that both intentionality and nonverbal reference are capacities shared by humans with our nearest living relatives, the great apes.

Animal Communication↗