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Interesting TED Talks: Faith Jegede: “What I’ve learned from my autistic brothers”

10/11/2012 1 comment

Faith Jegede tells the moving and funny story of growing up with her two brothers, both autistic — and both extraordinary. In this talk from the TED Talent Search, she reminds us to pursue a life beyond what is normal.

Writer Faith Jegede draws on her experiences growing up with two autistic brothers in order to spread awareness and understanding about this increasingly common diagnosis (from TED)

 

 

I was pleasantly surprised by this. Some very interesting points about “normality” that are often forgotten by scientists/clinicians/researchers/etc.

Female-To-Male Transsexual People and Autistic Traits

27/05/2012 1 comment

The ‘extreme male brain’ theory suggests females with Autism Spectrum Conditions are hyper-masculinized in certain aspects of behaviour.  Jones and colleagues (2007) predicted that females with Gender Identity Disorder would have elevated  Autism Spectrum Quotient (AQ) scores.

AQ scores from five groups were compared: the first group consisted of 61 transmen (female-to-male transsexual people, the second of 198 transwomen (male-to-female transsexual people), the third one of 76 typical males, the fourth of 98 typical females, and the fifth of 125 individuals with Asperger Syndrome (AS).

Autism Spectrum Conditions (ASC) are characterized by difficulties in social interaction and communication, alongside restricted interests and repetitive behavior (APA 1994). The diagnosis of ASC is more common in males. The Extreme Male Brain (EMB) theory of autism proposed by Baron-Cohen and Hammer in 1997 attempted to explain this . According to the EMB individuals with an ASC display an extreme of the typical male pattern of cognition and behaviour.

Studies on females with ASC have found that they are hyper-masculinized in specific aspects of behaviour and cognition. Also, women with ASC report higher rates of tomboyism in childhood (Ingudomnukul et al., 2007).  Also, female-to-male (FM) transsexuals (referred to as ‘transmen’) follow a handedness pattern more similar to genetic males (less exclusively right-handed) (Green & Young, 2001) and the same has been found among women with ASC (Soper et al., 1986).

Jones et al. used the AQ to test the specific prediction from the EMB theory that transmen will have more autistic traits than typical women, and that a higher proportion will score in the ASC range for autistic traits. Their scores were compared to maleto-female transsexual people (‘transwomen’).

The AQ is a self-report questionnaire published by Baron-Cohen and colleagues in 2001 and consists of 50 item. It assesses social skills, communication skills, imagination abilities, attention switching, and attention to details.

Scores on the AQ can be used to categorise individuals as having the ‘broader autism phenotype’ (BAP: defined as AQ 23-28), ‘medium autism phenotype’ (MAP: defined as AQ 29-34) or ‘narrow autism phenotype’ (NAP: defined  as AQ 35+) (Wheelwright et al. 2010).  The transmen had significantly more autistic traits than control men and their mean AQ score lied in the BAP range. Approximately 30% of the transmen group had an AQ in the MAP or NAP range. Transmen had a 11-fold increase in the rate of NAP relative to typical males.

This study confirms clinical case studies and reports in adolescents and children that genetic females with Gender Identity Disorder (GID) have an increased number of autistic traits. The results of this study show that transmen relative to control women exhibit more autistic traits.  In addition to that, transmen had more autistic traits than control men, and their mean AQ score lies in the Broader Autism Phenotype (BAP) range.

The authors speculated:

that this increased number of autistic traits is likely to have made the transmen (in their childhood and adolescence) less able to assimilate in a female peer group, instead gravitating towards males. This may also have led to difficulties socializing in a female peer group, and a feeling of belonging more in a male group, thus increasing the probability of GID.

Very interesting findings but what I’ve been thinking while reading the paper was the possible effects of hormone treatment on the AQ scores. Jones et al. had an answer to that:

…a proportion of the transsexual groups were taking hormone treatments and for obvious ethical reasons it was not possible to control for this factor but it is of interest that analysis comparing those on or off testosterone treatment did not lead to significantly different AQ scores.

They go on suggesting that current sex steroid levels do not seem to affect AQ, which seem to depend mostly on foetal levels of sex steroids.

ResearchBlogging.orgJones RM, Wheelwright S, Farrell K, Martin E, Green R, Di Ceglie D, & Baron-Cohen S (2011). Brief report: female-to-male transsexual people and autistic traits. Journal of autism and developmental disorders, 42 (2), 301-6 PMID: 21448752

So… who likes sports?

There’s no doubt that watching sports is a very popular pastime.

In 2010 alone, there were over 40,500 h of live sporting events on broadcast and cable TV (Neilsen Company, 2011)

However, little is know about the personality  traits and the identity of people who like watching sports*.

Appelbaum and colleagues gathered  broad demographic, physiological, clinical, psychological, and pastime-preference information from a sample of 293 individuals to see what factors most reliably predicted sport spectating habits. First, they examined possible relationships between watching sports and physiological measures. Saliva was collected and baseline testosterone and cortisol levels were measured. Moreover, 2D:4D digit ratio was calculated for each individual. This measurement is a proxy of prenatal androgen exposure and has been shown to correlate with particular disorders. Secondly, they administered self-report scales looking at ADHD (Jasper/Goldberg adult ADD/ADHD questionnaire) and autism traits (AQ; Autism Spectrum Quotient). Furthermore, they investigated the relationship between sports spectating and personality traits. The NEO personality inventory (NEO-PI-R), which measures the “BigFive” personality traits, and the Barratt Impulsivity Scale (BIS-11) were used. Finally, Appelbaum et al. asked their participants about the pastime activities. The pastime involvement questionnaire asked participants how many hours a week they spend on a number of activities such as reading, playing sports, watching television and movies, and listening to music.

As expected gender and age significantly accounted for the variability in the results. Young males reported spending more time watching sports.  High levels of sports spectating were correlated with higher levels of extraversion, excitement seeking and gregariousness on the personality questionnaires. The participants who reported spending more hours watching sports also engaged more in specific pastime activities, such as participating in sports and exercise, watching TV/movies, and playing video games. No differences were observed in the self-report scales. More specifically, no differences in ADHD or autism symptoms were found between people who watch sports and people who don’t. Likewise, the authors didn’t find any relationship between digit ratio and sports watching.

No relationship was found between baseline concentrations of cortisol or testosterone and sports spectating. This came as a surprise to the authors who list a number of previous studies that identified higher concentrations of testosterone and cortisol in people who like sports. Now, before jumping to conclusions, take into account that the sport spectators in this study is not your average sports fan! Previous literature has identified two related concepts; fans and spectators. Even though those groups have some overlapping qualities, there are some key differences.

…a fan is typically associated with an emotional link to a sport or team, while a spectator is a more neutral descriptor of an individual who consumes sports (Wann & Dolan, 2001).

In this study, they were interested only in sports spectators (defined by the hours they spend watching sports). This could possibly explain why no relationship was found between sports watching and cortisol concentration.

Also, I think that there must be differences between spectators of different types of sports (e.g. rugby, tennis, snooker). The authors didn’t examined this, but it’d be interesting to see a study looking at differences in sports preferences between people who enjoy watching sports.

ResearchBlogging.orgGregory Appelbaum, L., Cain, M., Darling, E., Stanton, S., Nguyen, M., & Mitroff, S. (2011). What is the identity of a sports spectator? Personality and Individual Differences DOI: 10.1016/j.paid.2011.10.048

* Academics are probably not very keen on sports?

Prospective Memory in ASD

25/03/2010 3 comments

ResearchBlogging.orgProspective Memory (PM or ProM- I’ll be using the term PM) is defined as a number of functions that enable a person to carry out an intended act after a delay (Burgess et al., 2001). A significant number (50–80%) of all everyday memory problems are, at least in part, PM problems (Kliegel & Martin, 2003). However, PM is one of the least studied forms of memory in cognitive neuroscience.

PM is divided into a retrospective and a prospective component (Einstein & McDaniel, 1990). The retrospective component involves the retention of the action to be performed and the prospective entails the retrieval of the action, after the identification of the encoded cue. Both frontal lobe areas and the medial temporal lobes (MTL) are thought to play a role in PM. One area constantly associated with PM tasks from various lesions and neuroimaging studies (Simons et al., 2006; Miller & Cohen, 2001) is the frontopolar and superior rostral aspects of the frontal lobes (approximating BA10).

A number of cognitive abilities that have been associated with rostral PFC seem to be impaired in ASD (Hill, 2004; also see older post on Executive Functions in ASD.)

Even though evidence suggests that PM could be impaired in ASD, only a limited number of studies have been done to examine this. Mackinlay et al. (2006) investigated PM in children with ASD and found that they had difficulties in planning, carrying out and switching between different tasks.

Recently, Altgassen et al. (2009) found reduced performance in ASD as compared to controls in a time-based PM task and that was attributed to poor task monitoring and task organization. Monitoring, like many executive functions, also is associated with frontal lobe function (Shallice & Burgess, 1991).

Only one study (Altgassen et al., 2009b) has looked into event-based PM on children with ASD. The participants were 19 high-functioning children and adolescents with ASD and 19 typically developing controls. They were asked to work simultaneously on an ongoing and a PM task. The ongoing task was a visuo-spatial working memory task and for the PM task, they were to press the certain key whenever the background colour of the screen changed to yellow. Dependent measures were accuracy and reaction times. They also measured subjective everyday executive functioning by using The DEX questionnaire, which was filled by the parents of the subjects. No significant differences were found between the two groups in any of the measures apart from the subjective everyday ratings. The parents of the participants with ASD rated their children’s performance as poorer than controls’ parents.

Here’s the explanation that Altgassen et al. (2009b) give about the deficits found in time-based PM, but not in event-based PM:

…in comparison to time-based tasks or complex multitasking paradigms simple, event-based PM tasks are very structured, and similarly to cued (retrospective) recall provide (here: visual) cues that may support retrieval of the intended action and put lower demands on self-initiated strategy application which may decrease executive control demands and thus enable individuals with ASD to preserved event-based PM
performance [23]…

Interestingly, studies show that people with ASD seem to have deficits mostly in ill-structured tasks, while they perform near or at control levels at well-structured tests (White et al., 2009). In this paper

the ASD group tended to create fewer spontaneous strategies and exhibit more idiosyncratic behavior, which particularly disadvantaged them on the more open-ended tasks.

It would be very interesting to see if future studies will replicate Altgassen et al.’s results using a bigger sample or a more difficult task requiring higher working memory load.

Altgassen, M., Schmitz-Hübsch, M., & Kliegel, M. (2009). Event-based prospective memory performance in autism spectrum disorder Journal of Neurodevelopmental Disorders, 2 (1), 2-8 DOI: 10.1007/s11689-009-9030-y

Executive Functions in ASD

braincopyThere are three key theories that attempt to explain the links between brain and behaviour in Autistic spectrum disorders (ASD): the Theory of Mind Deficit Hypothesis (for a review see Baron-Cohen, 2001), the Weak Central Coherence (Happé & Frith, 2006) and that of Executive Dysfunction (Hill, 2004).

Executive functions is an umbrella term for a number of cognitive and behavioural capacities such as planning, working memory, inhibition, mental flexibility, multitasking, initiation and monitoring of action (Gilbert & Burgess, 2008). Executive functions are usually impaired in patients with frontal lobe damage and in many neurodevelopmental disorders like ADHD, OCD, schizophrenia and ASD.  These disorders are likely to involve deficits in the frontal lobes.

Autistic people seem to be impaired only in some tests of executive functions, especially those involving multitasking (“Six Element Test”, Hill & Bird, 2006), planning (“Tower of London”, Ozonoff et al, 1991) and Inhibition (“Go/No-Go task” ,  Ozonoff & Strayer, 1997). Deficits have also been shown in planning and abstract problem solving tasks (Hill & Bird, 2006). On other tests their performance is equal or superior to control groups (Minshew, Goldstein & Siegel, 1997). It’s worth noting that ASD individuals are mostly impaired in newer tests rather than classical tests of executive functions (Hill & Bird, 2006, Gilbert et al., 2008). These findings could be due to the heterogeneity of different tests of executive function (Gilbert et al., 2008).

Most of the tasks in which ASD individuals show deficits are thought to be mediated by the frontal lobes. A number of studies have identified several several cortical, subcortical abnormalities and functional differences (Kawakubo et al., 2009; Schmitz et al., 2005).

The theory of cortical underconnectivity  posits a deficit in integration of information at the neural and cognitive levels (Just et al., 2006). Findings from neuroimaging studies such as the thinning of the corpus callosum and the reduced connectivity, especially with the frontal areas and also the fusiform face area in ASD people support the theory of underconnectivity (Hughes, 2007). Recently, increased activation in medial rostral prefrontal cortex (BA 10) during tasks of stimulus-oriented versus stimulus-independent attention has been found in people with ASD (Gilbert et al., 2008). Previous studies has shown the importance of rPFC in selection between stimulus-oriented and stimulus-independent thought (Gilbert, Frith & Burgess, 2005; Ramnani & Owen, 2004). On the same task the control group showed greater activity primarily in bilateral occipital cortex. According to Gilbert et al.:

“This suggests that the control group were able to modulate activity in early visual cortex according to the attentional demands of the task to a greater degree than the ASD group. The stimuli were matched between the two conditions, suggesting attentional modulation rather than an effect of stimulus-category. This finding is consistent with the suggestion of functional underconnectivity in ASD”

Further Readings

Happé, F., & Frith, U. (1996). The neuropsychology of autism.Brain, 19, 1377-1400.

White, S., O’Reilly, H., & Frith, U. (2009). Big heads, small details and autism. Neuropsychologia, 47(5), 1274-1281.‎

Mundy, P. (2003). The Neural Basis of Social Impairments in Autism: The Role of the Dorsal Medial-Frontal Cortex and Anterior Cingulate System. Journal of Child Psychology & Psychiatry, 44, 793-809

Happé, F., Booth, R., Charlton, R. & Hughes, C. (2006) Executive function deficits in Autism Spectrum Disorders and Attention-Deficit/Hyperactivity Disorder: Examining profiles across domains and ages. Brain and Cognition.

Baron-Cohen, S., & Swettenham, J. (1998) Theory of mind in autism: Its relationship to executive function and central coherence. In D.J. Cohen & F.R. Volkmar (Eds.), Handbook of autism and pervasive developmental disorders (2nd ed., pp. 880–893). New York: Wiley.

Martin, I. and McDonald, S. (2003). Weak coherence, no theory of mind, or executive dysfunction? solving the puzzle of pragmatic language disorders. Brain and language, 85(3):451-466.

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