This paper examines conditions that do or do not lead to accurate judgments of frequency (JOF) and judgments of duration (JOD). In three experiments, duration and frequency of visually presented stimuli are varied orthogonally in a within-subjects design. Experiment 1 reveals an asymmetric judgment pattern. JOFs reflected actual presentation frequency quite accurately and were unbiased by exposure duration. Conversely, JODs were almost insensitive to actual exposure duration and were systematically biased by presentation frequency. We show, however, that a tendency towards a symmetric judgment pattern can be obtained by manipulating encoding conditions. Sustaining attention during encoding (Experiment 2) or enhancing richness of the encoded stimuli (Experiment 3) increases judgment sensitivity in JOD and yields biases in both directions (JOF biased by exposure duration, JOD biased by presentation frequency). The implications of these findings for underlying memory mechanisms are discussed.

Biases in people’s judgments of time saved by increasing the speed of an activity have been studied mainly with hypothetical scenarios (Svenson, 2008). The present study asked whether the classic time-saving bias persists as a perceptual bias when we control the speed of an activity and assess the perceived time elapsed at different speeds. Specifically, we investigated the time-saving bias in a driving simulator. Each participant was asked to first drive a distance at a given speed and then drive the same distance again at the speed she or he judged necessary to gain exactly three minutes in travel time compared to the first trip. We found that that the time-saving bias applies to active driving and that it affects the choice of driving speed. The drivers’ time-saving judgements show that the perception of the time elapsed while driving does not eliminate the time-saving bias.

Previous studies have demonstrated that emotional facial expressions alter temporal judgments. Moreover, while some studies conducted with Parkinson's disease (PD) patients suggest dysfunction in the recognition of emotional facial expression, others have shown a dysfunction in time perception. In the present study, we investigate the magnitude of temporal distortions caused by the presentation of emotional facial expressions (anger, shame, and neutral) in PD patients and controls. Twenty-five older adults with PD and 17 healthy older adults took part in the present study. PD patients were divided into two sub-groups, with and without mild cognitive impairment (MCI), based on their neuropsychological performance. Participants were tested with a time bisection task with standard intervals lasting 400 ms and 1600 ms. The effect of facial emotional stimuli on time perception was evident in all participants, yet the effect was greater for PD-MCI patients. Furthermore, PD-MCI patients were more likely to underestimate long and overestimate short temporal intervals than PD-non-MCI patients and controls. Temporal impairment in PD-MCI patients seem to be mainly caused by a memory dysfunction. (JINS, 2016, 22, 890–899)

The ability to accurately perceive the passage of time relies on several neurocognitive abilities, including attention, memory, and executive functions, which are domains commonly affected in persons living with HIV disease. The current study examined time estimation and production and their neurocognitive correlates in a sample of 53 HIV+ individuals with HIV-associated neurocognitive disorders (HAND), 120 HIV+ individuals without HAND, and 113 HIV− individuals. Results revealed a moderate main effect of HAND on time estimation and a trend-level effect on time production, but no interaction between HAND and time interval duration. Correlational analyses revealed that time estimation in the HIV+ group was associated with attention, episodic memory and time-based prospective memory. Findings indicate that individuals with HAND evidence deficits in time interval judgment suggestive of failures in basic attentional and memory processes. (JINS, 2015, 21, 175–181)

The current study examined whether healthy older adults (OA) and individuals at the earliest stages of dementia of the Alzheimer's type (DAT) differ from younger adults (YA) and from each other on a simple, extended continuous tapping task using intervals (500 ms, 1000 ms, and 1500 ms) thought to differentially engage attentional control systems. OA groups sped up their tapping at the slowest target rate compared to the YA; this pattern was magnified in the early stage DAT groups. Performance variability appeared especially sensitive to DAT-related changes, as reliable differences between healthy OA and very mild DAT individuals emerged for multiple tap rates. These differences are proposed to result from breakdowns in attentional control that disrupt error-correction processes and the ability to resolve discrepancies between internally-generated temporal expectancies and the external temporal demands of the repetitive timing task. (JINS, 2012, 18, 1–12)

Nonadherence to combination antiretroviral (ARV) therapies (cART) is highly prevalent and significantly increases the risk of adverse human immunodeficiency virus (HIV) disease outcomes. The current study evaluated the hypothesis that prospective memory—a dissociable aspect of episodic memory describing the ability to execute a future intention—plays an important role in successful cART adherence. Seventy-nine individuals with HIV infection who were prescribed at least one ARV medication underwent a comprehensive neuropsychological and neuromedical evaluation prior to completing a 1-month observation of their cART adherence as measured by electronic medication monitoring. Nonadherent individuals (n = 31) demonstrated significantly poorer prospective memory functioning as compared to adherent persons (n = 48), particularly on an index of time-based ProM (i.e., elevated loss of time errors). Deficits in time-based prospective memory were independently predictive of cART nonadherence, even after considering the possible influence of established predictors of adherence, such as general cognitive impairment (e.g., retrospective learning and memory) and psychiatric comorbidity (e.g., depression). These findings extend a nascent literature showing that impairment in time-based prospective memory significantly increases the risk of medication nonadherence and therefore may guide the development of novel strategies for intervention. (JINS, 2009, 15, 42–52.)

Huntington's disease (HD) is a neurodegenerative disorder diagnosed clinically with the development of choreiform movements. However, neuropsychological studies have demonstrated cognitive and psychiatric changes during the preclinical phase (pre-HD) prior to formal diagnosis. Previous studies have demonstrated the sensitivity of time reproduction tasks to basal ganglia pathology, as seen in clinical HD and Parkinson's disease. In this study, 29 pre-HD participants, ranging from 3 to 39 years from estimated onset (YEO) of HD based on genetic testing and chronological age, were administered the paced finger-tapping task using target intervals of 600 and 1200 ms. Mean inter-response interval, a measure of timing accuracy, did not systematically deviate from the target interval as a function of YEO. In contrast, timing variability increased curvilinearly as a function of YEO, but not with chronological age alone. Motor timing variability, but not accuracy, may serve as a marker to define the earliest behavioral changes in HD. The present study is among the first to examine the relationship between behavioral measures and YEO in pre-HD. (JINS, 2007, 13, 539–543.)

Objective: The experience of time is strongly related to our momentary mood states. Patients with a life-threatening illness experience an extreme change in mood and suffer from psychological distress that can develop into clinically relevant psychiatric disorders, like anxiety and depression. The aim of this study was to investigate the associations among the subjective perception of time, psychological distress, and quality of life in patients with hematological malignancies.

Methods: Eighty-eight inpatients with hematological malignancies rated how fast time passes subjectively on a visual analog scale and prospectively estimated a time span of 13 min. The Hospital Anxiety and Depression Scale (HADS) self-report measures of health-related quality of life (FACT-G) and spiritual well-being (FACIT-Sp) were employed to assess psychological distress and quality of life.

Results: Those patients who reported a lower quality of life, less spiritual well-being, and more anxiety experienced a slower passage of subjective time and overestimated the 13-min time interval.

Significance of results: Our interpretation of the results is that patients with a life-threatening illness who show symptoms of psychological distress draw attention away from meaningful thoughts and actions and, thus, experience time as passing more slowly. An altered sense of time can be a sign of mental suffering, which should be addressed within psycho-oncological interventions. As this is the first study to demonstrate this relation in cancer patients, further research is needed to investigate the experience of time and its relation to meaning as an issue in clinical diagnostics.

Studies concerning time perception lack a validated assessment tool and a consensual “gold-standard” measure. Moreover, the present evidence suggests modification of timing with aging. This study aimed to develop and validate a neuropsychological tool to measure time perception and to study temporal perception with aging. Eighty-six healthy participants, aged 15–90 years old, were asked to verbally estimate and produce empty intervals signaled by auditory beeps, of 7-, 32-, and 58-s duration. Two tests were used as “gold-standards”: estimation of the duration of time necessary to draw a clock (“clock time”) and estimation of the duration of neuropsychological evaluation (“global time”). Results showed a correlation between estimation and production (p < .01) and a correlation between estimation or production and “global time” (p < .01). The correlation between either estimation or production and age (p < .01), suggested a faster “internal-clock” in the older participants. However, this finding lost significance when controlled for literacy. The results suggest that these tests are potentially a useful tool to measure subjective perception of time. They also corroborate the hypothesis of a change in subjective time perception with aging. It was not possible to conclude if this effect was a specific result of aging or biased by the interference of literacy. (JINS, 2004, 10, 332–341.)

We examined short duration perception (400 ms), long duration estimation (30 and 60 min), and spatiotemporal estimation in long-term survivors of childhood cerebellar tumors with a mean time since diagnosis of 14.2 years. Groups of individuals with tumors treated with surgery only (astrocytoma, N = 20) were compared to those with tumors treated with surgery, focal radiation, and craniospinal radiation (medulloblastoma, N = 20), and to age- matched controls (N = 40). Childhood lesions of the cerebellum produced enduring deficits in short-duration perception, but spared the ability to functionally estimate long durations, regardless of the pathology or treatment of the tumor. Evidence did not support any functional recovery over time of the cerebellar system that underlies short-duration perception. Younger age at treatment was not a protective factor. Although no group differences were present in the functional measures of long-duration estimation, tumor-related prospective memory deficits interfered with the ability to produce long-duration prospective estimates. The utilization of sensory and somatomotor information to refine real-world spatiotemporal estimates was compromised in the medulloblastoma group only. (JINS, 2000, 6, 682–692.)