Autistic traits are associated with enhanced working memory capacity for abstract visual stimuli.

We tested whether the association between autistic traits and enhanced performance in visual-perceptual tasks extends to visual working memory capacity. We predicted that any positive effect of autistic traits on visual working memory performance would be greatest during domain-specific tasks, in which visual resources must be relied upon. We used a visual 'matrix' task, involving recall of black-and-white chequered patterns which increased in size, to establish participants' capacity (span). We assessed 144 young adults' (M = 22.0 years, SD = 2.5) performance on abstract, 'low semantic' versus 'high semantic' task versions. The latter offered multimodal coding due to the availability of long-term memory resources that could supplement visual working memory. Participants also completed measures of autistic traits and trait anxiety. Autistic traits, especially Attention to Detail, Attention Switching, and Communication, positively predicted visual working memory capacity, specifically in the low semantic task, which relies on visual working memory resources. Autistic traits are therefore associated with enhanced processing and recall of visual information. The benefit is removed, however, when multimodal coding may be incorporated, emphasising the visual nature of the benefit. Strengths in focused attention to detail therefore appear to benefit domain-specific visual working memory task performance.

Social identities and mental well-being in autistic adults.

LAY ABSTRACT: Social identities are groups that we are part of and influence how we think about ourselves. However, up until now there has been little examination of the groups that autistic people may belong to, and how these groups may influence their mental health. This survey-based study investigated whether autistic adults answer questions about social groups in a similar way to non-autistic non-autistic adults, including the types and number of social groups they may belong to, and whether these are associated with depression, anxiety and positive traits of mental well-being. In total, 184 autistic adults completed an online survey with questionnaires about their demographics, social groups and mental health. The results found that autistic adults reported on their social groups similarly to non-autistic people. There was a variety in the types and numbers of groups that autistic adults identified with. Some participants reported having no groups that they identified with, whereas others reported up to four groups. These included other autistic people, their family, friends, work colleagues and activity clubs among others. Autistic adults who felt connected with more groups reported better mental well-being. Feelings of connection to other autistic people and the family were also associated with better mental well-being. These results show that it is important for autistic people to be given opportunity to be part of groups that are meaningful to them, as this may be beneficial for their mental health.

Autistic Traits and Enhanced Perceptual Representation of Pitch and Time.

Enhanced basic perceptual discrimination has been reported for pitch in individuals with autism spectrum conditions. We test whether there is a correlational pattern of enhancement across the broader autism phenotype and whether this correlation occurs for the discrimination of pitch, time and loudness. Scores on the Autism-Spectrum Quotient correlated significantly with the pitch discrimination (r = -0.51, p < 0.05) and the time-interval discrimination (r = -0.45, p < 0.05) task that were based on a fixed reference. No correlation was found for intensity discrimination based on a fixed reference, nor for a variable reference based time-interval discrimination. The correlations suggest a relationship between autistic traits and the ability to form an enhanced, stable and highly accurate representation of auditory events in the pitch and time dimensions.

Categorical Speech Perception in Adults with Autism Spectrum Conditions.

This study tested whether individuals with autism spectrum conditions (n = 23) show enhanced discrimination of acoustic differences that signal a linguistic contrast (i.e., /g/ versus /k/ as in 'goat' and 'coat') and whether they process such differences in a less categorical fashion as compared with 23 IQ-matched typically developed adults. Tasks administered were nonverbal IQ, verbal IQ, 5 language measures, a speech perception task, and the ADOS. The speech perception task measured the discrimination of paired exemplars along the /g/-/k/ continuum. Individuals with autism spectrum conditions did not show enhanced discrimination of speech perception. Categorical speech perception was correlated with verbal ability of reading, lexical decision, and verbal IQ in individuals with autism spectrum conditions.

Investigating the structure of the autism-spectrum quotient using Mokken scaling.

Traits similar to those shown in autism spectrum condition (ASC) are apparent in relatives of individuals with ASC, and in the general population without necessarily meeting diagnostic criteria for an ASC. We assess whether the Autism-Spectrum Quotient (AQ), a self-report measure, has hierarchical properties using Mokken scaling. Hierarchical scales allow the presence of a latent trait to be identified by discovering whether and how many specific items form an ordered array along it. Data were collected from 2 groups: (1) people with ASC (n = 449: 240 males, 209 females, M(age) 35.4 years, SD = 12.8) and (2) university students (n = 943: 465 males, 475 females, M(age) = 23.0 years, SD = 8.4). A single Mokken scale was obtained in the data from university students and 3 scales were obtained in the data from people with ASC. The scales all showed moderate Mokken scaling properties with the single scale obtained from university students showing weak invariant item ordering and 2 of the scales from people with ASC showing weak invariant item ordering. The AQ formed reliable Mokken scales. There was a large overlap between the scale from the university student sample and the sample with ASC, with the first scale, relating to social interaction, being almost identical. The present study confirms the utility of the AQ as a single instrument that can dimensionalize autistic traits in both university student and clinical samples of ASC, and confirms that items of the AQ are consistently ordered relative to one another.

Lexical effects on children's speech processing: individual differences reflected in the Autism-Spectrum Quotient (AQ).

PURPOSE: This study was undertaken to examine whether children exhibit the same relationship that adults show between lexical influence on phoneme identification and individual variation on the Autism-Spectrum Quotient (AQ). METHOD: Data from 62 4- to 7-year-olds with no diagnosis of autism were analyzed. The main task involved identification of the initial sound in pairs of voice-onset time continua with a real word on one end and a nonword on the other (e.g., gift-kift, giss-kiss). Participants were also given the children's version of the AQ and a 2nd instrument related to autistic-like traits, the Social Responsiveness Scale (SRS). RESULTS: The lexical shift was related to the AQ (particularly to its Attention Switching subscale) but not to the SRS. CONCLUSIONS: The size of lexical effects on children's speech perception can be predicted by AQ scores but not necessarily by other measures of autism-like traits. The results indicate that speech perception in children manifests individual differences along some general dimension of cognitive style reflected in the AQ, possibly in relation to local/global information processing.

Emotional recognition in autism spectrum conditions from voices and faces.

The present study reports on a new vocal emotion recognition task and assesses whether people with autism spectrum conditions (ASC) perform differently from typically developed individuals on tests of emotional identification from both the face and the voice. The new test of vocal emotion contained trials in which the vocal emotion of the sentence were congruent, incongruent, or neutral with respect to the semantic content. We also included a condition in which there was no semantic content (an 'mmm' was uttered using an emotional tone). Performance was compared between 11 adults with ASC and 14 typically developed adults. Identification of emotion from sentences in which the vocal emotion and the meaning of sentence were congruent was similar in people with ASC and a typically developed comparison group. However, the comparison group was more accurate at identifying the emotion in the voice from incongruent and neutral trials, and also from trials with no semantic content. The results of the vocal emotion task were correlated with performance on a face emotion recognition task. In decoding emotion from spoken utterances, individuals with ASC relied more on verbal semantics than did typically developed individuals, presumably as a strategy to compensate for their difficulties in using prosodic cues to recognize emotions.

Visual/verbal-analytic reasoning bias as a function of self-reported autistic-like traits: a study of typically developing individuals solving Raven's Advanced Progressive Matrices.

People with autism spectrum condition (ASC) perform well on Raven's matrices, a test which loads highly on the general factor in intelligence. However, the mechanisms supporting enhanced performance on the test are poorly understood. Evidence is accumulating that milder variants of the ASC phenotype are present in typically developing individuals, and that those who are further along the autistic-like trait spectrum show similar patterns of abilities and impairments as people with clinically diagnosed ASC. We investigated whether self-reported autistic-like traits in a university student sample, assessed using the Autism-Spectrum Quotient (AQ; Baron-Cohen, Wheelwright, Skinner, et al., 2001), predict performance on Raven's Advanced Progressive Matrices. We found that reporting poorer social skills but better attention switching predicted a higher Advanced matrices score overall. DeShon, Chan, and Weissbein (1995) classified Advanced matrices items as requiring a visuospatial, or a verbal-analytic strategy. We hypothesised that higher AQ scores would predict better performance on visuospatial items than on verbal-analytic items. This prediction was confirmed. These results are consistent with the continuum view and can be explained by the enhanced perceptual functioning theory of performance peaks in ASC. The results also confirm a new prediction about Raven's Advanced Progressive Matrices performance in people with ASC.

Autistic traits predict performance on the block design.

The Autism-Spectrum Quotient (AQ) has been developed to measure the degree to which an adult with normal intelligence has autistic traits. Although use of the AQ has resulted in a number of important findings, few studies have assessed whether scores predict cognitive aspects of ASD. This study assessed whether AQ scores predicted performance on an adapted block design. The test was adapted with a 'whole' and a 'segmented' task. High AQ scorers performed better than low scorers on the 'whole' task in the block design but performed equivalently on the 'segmented' task, as would be predicted in the autism spectrum. These findings add to the evidence showing construct validity for the AQ.

Sensory Characteristics in ASD.

In this paper, we review evidence regarding differences in the types of sensory experiences of persons with ASD with respect to both unisensory and multisensory processing. We discuss selfreports, carer questionnaires as well as perceptual processing differences found in the laboratory. Incoming information is processed through one or more of our senses and fundamental differences in the processing of information from any sensory modality or combination of sensory modalities are likely to have cascading effects on the way individuals with ASD experience the world around them, effects that can have both positive and negative impact on a individual with ASD's quality of life.

Lexical effects on speech perception in individuals with "autistic" traits.

It has been claimed that Autism Spectrum Disorder (ASD) is characterized by a limited ability to process perceptual stimuli in reference to the contextual information of the percept. Such a connection between a nonholistic processing style and behavioral traits associated with ASD is thought to exist also within the neurotypical population albeit in a more subtle way. We examined this hypothesis with respect to auditory speech perception, by testing whether the extent to which phonetic categorization shifts to make the percept a known word (i.e., the 'Ganong effect') is weakened as a function of autistic traits in neurotypicals. Fifty-five university students were given the Autism-Spectrum Quotient (AQ) and a segment identification test using two word-to-nonword Voice Onset Time (VOT) continua (kiss-giss and gift-kift). A significant negative correlation was found between the total AQ score and the identification shift that occurred between the continua. The AQ score did not correlate with scores on separately administered VOT discrimination, auditory lexical decision, or verbal IQ, thus ruling out enhanced auditory sensitivity, slower lexical access or verbal intelligence as explanations of the AQ-related shift in phonetic categorization.

Presentation of depression in autism and Asperger syndrome: a review.

Depression is common in autism and Asperger syndrome, but despite this, there has been little research into this issue. This review considers the current literature on the prevalence, presentation, treatment and assessment of depression in autism and Asperger syndrome. There are diagnostic difficulties when considering depression in autism and Asperger syndrome, as the characteristics of these disorders, such as social withdrawal and appetite and sleep disturbance, are also core symptoms of depression. Impaired verbal and non-verbal communication can mask the symptoms of depression. Symptoms associated with autism and Asperger syndrome such as obsessionality and self-injury may be increased during an episode of depression. There is a clear need to develop specific tools both for diagnostic purposes and for measurement of depression in autism and Asperger syndrome in order to help alleviate the distress caused by this treatable illness.

High harm avoidance and low self-directedness in euthymic young adults with recurrent, early-onset depression.

BACKGROUND: The personality dimensions of harm avoidance (HA) and self-directedness (SD), as measured by the Temperament and Character Inventory (TCI), have been widely associated with depression and there is preliminary evidence that they may represent trait markers for depression. However, many studies in this area are limited by the use of heterogeneous samples of depressed patients and by the confounding effect of depressed mood during personality testing. The current study compares TCI personality dimension scores in a group of euthymic young adults with recurrent early-onset major depressive disorder (RE-MDD) to well-matched euthymic controls. METHODS: Fifty-two young adults with a past history of RE-MDD were recruited from consecutive referrals to a psychiatric clinic at a university health service. Eighty nine controls were also recruited. Euthymia was established in patients by a score of less than 9 on the Hamilton Rating Scale for Depression (HRSD) and in controls by a Becks Depression Inventory (BDI) score of less than 10. All participants completed the TCI-125. RESULTS: Patients and controls were well matched in terms of sociodemographic profile. Euthymic RE-MDD patients scored significantly higher than controls on the temperament dimension of harm avoidance (HA; mean score 14.5 versus 7.8, p<0.0001) and significantly lower than controls on the character dimension of self-directedness (SD; mean score 14.1 versus 19.9, p<0.0001). Covariance analysis suggested that both HA and SD contributed independently to the familial risk of depression. LIMITATIONS: Subjects and controls all came from relatively affluent social backgrounds-these findings may not generalise to more socioeconomically diverse populations. The possibility of a 'scarring effect' of depressive episodes on self-reported personality dimension scores cannot be excluded. CONCLUSIONS: High HA and low SD represent trait markers for liability to recurrent major depressive disorder in young adults. Further research is needed to replicate these findings and to assess the contribution that the experience of depressive episodes makes to self-reported personality dimension scores.

The effects of acute tryptophan depletion on neuropsychological function.

Serotonin (5-HT, 5-hydroxytryptamine) may have an important role in the maintenance of normal neuropsychological functioning. The method of acute tryptophan depletion (ATD) provides a pharmacological challenge by which central 5-HT levels can be temporarily decreased and effects on learning, memory and mood examined. Twenty healthy male volunteers were recruited to take part in this within-subject, double-blind, crossover study. Neuropsychological function was evaluated 4-6 h after ingestion of a control or 52 g tryptophan (TRP) depleting amino-acid drink. ATD significantly lowered levels of plasma total and free TRP (p < 0.001), but this did not affect mood or performance on tests of verbal and visuo-spatial learning and memory, attention or executive function. These results contradict previous findings; however, the degree of disruption of central 5-HT levels resulting from the use of the 52 g amino-acid protocol may be an important factor in explaining the lack of effect. By utilizing more specific probes of individual 5-HT receptor subtypes, future studies can fully explore the role of 5-HT in neuropsychological functioning and may elucidate the factors determining vulnerability to the effects of serotonergic dysfunction.

Absence of auditory 'global interference' in autism.

There has been considerable recent interest in the cognitive style of individuals with Autism Spectrum Disorder (ASD). One theory, that of weak central coherence, concerns an inability to combine stimulus details into a coherent whole. Here we test this theory in the case of sound patterns, using a new definition of the details (local structure) and the coherent whole (global structure). Thirteen individuals with a diagnosis of autism or Asperger's syndrome and 15 control participants were administered auditory tests, where they were required to match local pitch direction changes between two auditory sequences. When the other local features of the sequence pairs were altered (the actual pitches and relative time points of pitch direction change), the control participants obtained lower scores compared with when these details were left unchanged. This can be attributed to interference from the global structure, defined as the combination of the local auditory details. In contrast, the participants with ASD did not obtain lower scores in the presence of such mismatches. This was attributed to the absence of interference from an auditory coherent whole. The results are consistent with the presence of abnormal interactions between local and global auditory perception in ASD.

Neuroticism as a predictor of mood change: the effects of tryptophan depletion.

BACKGROUND: Acute tryptophan depletion (ATD) results in a transient lowering of mood in patients recovered from depression and in healthy volunteers with a family history of affective disorders. The personality trait of neuroticism is strongly associated with depression. AIMS: To assess whether neuroticism predicts mood change in response to ATD in healthy volunteers. METHOD: Healthy volunteers who scored at the top and bottom fifth percentiles of neuroticism scores (17 and 15 respectively) were selected. In a double-blind, crossover study they received a tryptophan-free or a control drink. Mood and cognition were assessed. RESULTS: Neuroticism did not predict the amount of mood change following ATD but did moderate performance on the verbal fluency test. A family history of affective disorder (n=5) predicted mood change but not cognitive function following ATD. CONCLUSIONS: Neuroticism moderates aspects of cognitive function, but in this study it was not strongly related with mood change via serotonin.

Structural studies on ceramides as lithiated adducts by low energy collisional-activated dissociation tandem mass spectrometry with electrospray ionization.

We applied electrospray ionization (ESI) tandem quadrupole mass spectrometry to establish the fragmentation pathways of ceramides under low energy collisional-activated dissociation (CAD) by studying more than thirty compounds in nine subclasses. The product-ion spectra of the [M + Li]+ ions of ceramides contain abundant fragment ions that identify the fatty acyl substituent and the long-chain base (LCB) of the molecules, and thus, the structure of ceramides can be easily determined. Fragment ions specific to each ceramide subclasses are also observed. These feature ions permit differentiation among different ceramide subclasses. The ion series arising from the classical C-C bond cleavages that were reported in the fast-atom bombardment (FAB)-high energy tandem mass spectrometry is not observable; however, the product-ion spectra contain multiple fragment ions informative for structural characterization and isomer identification. We also investigated the tandem mass spectra of the fragment ions generated by in-source CAD (pseudo-MS3) and of the deuterium-labeling molecular species obtained by H/D exchange to support the ion structure assignments and the proposed fragmentation pathways that lead to the ion formation.