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Cake Is Better Than Sex: The Case of Asexuality

10/07/2012 5 comments

Recently, a “new” sexual orientation has started getting attention in the media, asexuality (or nonsexuality) (e.g., see recent article on the Metro)

But what is asexuality? No, we are not talking about the asexual reproduction of invertebrates and other lower-level vertebrates. Unfortunately, there is only a limited number of studies on asexuality. In fact, some psychologists still doubt its existence or see it as sexual dysfunction. In the UK about 1% of the population self-identify as asexual (Bogaert, 2004). A few definitions have been given for asexuality: Storms (1980) defines asexuality as the absence of sexual orientation. This is similar to the definition given by Bogaert (2004), who describes asexuality as the lack of basic attraction towards others. The definition adopted by the largest international online community of asexual individuals, the Asexual Visibility and Education Network (AVEN) is broader than the ones mentioned above. AVEN defines asexuality as the lack of sexual attraction. A quick look at the forums at AVEN reveals that there is a great level of variability between individuals who self-identify as asexuals. Some are characterised by a lack of romantic orientation, as well as sexual attraction. Other, however, experience romantic attraction and identify as hetero-romantic (romantically attracted to people from the opposite sex), homo-romantic asexuals (romantically attracted to people from the same sex), or bi-romantic asexuals (attracted to individuals from both sexes).

Orientation or… disorder?

Could some of the people who self-identify as asexual individuals have some hormonal imbalance or a disorder behind their lack of sexual attraction?

Some initial findings show that asexuality is not associated with higher rates of psychopathology (Brotto et al., 2010). However, a subset might fit the criteria for Schizoid Personality Disorder. Asexuality seems to be more common among adults with autism spectrum disorder (ASD) (Gilmour et al., 2012).

A recent study by Brotto & Yule (2011)  challenged the view that asexuality should be characterised as a sexual dysfunction. They did this by comparing genital (vaginal pulse amplitude; VPA) and subjective sexual arousal in asexual and non-asexual women.

Thirty-eight women between the ages of 19 and 55 years (10 heterosexual, 10 bisexual, 11 homosexual, and 7 asexual) viewed neutral and erotic audiovisual stimuli while VPA and self-reported sexual arousal and affect were measured. There were no significant group differences in the increased VPA and self-reported sexual arousal response to the erotic film between the groups. Asexuals showed significantly less positive affect, sensuality-sexual attraction, and self-reported autonomic arousal to the erotic film compared to the other groups; however, there were no group differences in negative affect or anxiety. Genital-subjective sexual arousal concordance was significantly positive for the asexual women and non-significant for the other three groups, suggesting higher levels of interoceptive awareness among asexuals. Taken together, the findings suggest normal subjective and physiological sexual arousal capacity in asexual women and challenge the view that asexuality should be characterized as a sexual dysfunction. (Brotto & Yule, 2011)

Is asexuality a new orientation?

In a sex obsessed society  the idea of individuals who don’t experience sexual attraction sounds alien. However, there is evidence from early studies by Kinsey (1948) that a small percentage of the population, a category he called “X” exhibited behaviour consistent with modern definitions of asexuality. The first known publication focused on asexuality was by Johnson in 1977. So, the answer is probably no. It was probably always around but it was the internet that gave asexual individuals the chance to meet others like them from all over the world.

Some theories suggest that asexuality is a product of modern society. In particular, Przybylo (2011) views asexuality as:

“both a product of and reaction against our sexusocial, disoriented postmodern here and now. This article also addresses the question of whether or not, and on what terms, asexuality may be considered a resistance against sexusociety”

References

Bogaert A.F. (2004) Asexuality: Its Prevalence and Associated Factors in a National Probability Sample. Journal of Sex Research, 41, 279-287

Brotto, L. A., Knudson, G., Inskip, J., Rhodes, K., & Erskine, Y. (2010). Asexuality: A mixed methods approach. Archives of Sexual Behavior, 39, 599-618.

Brotto, L. A., & Yule, M. A. (2011). Physiological and Subjective Sexual Arousal in Self-Identified Asexual Women, Archives of Sexual Behavior, 40, 699-712

Gilmour, L., Schalomon, P. M., and Smith, V. (2012). Sexuality in a community based sample of adults with autism spectrum disorder. Research in Autism Spectrum Disorders, 6(1):313-318.

Johnson, M. T. (1977). Asexual and Autoerotic Women: Two invisible groups. in ed. Gorchros H.L. and Gochros J.S. The Sexually Oppressed. New York: Associated Press.

Kinsey, Alfred C. (1948). Sexual Behavior in the Human Male. W.B. Saunders.

Przybylo, E. (2011) Crisis and safety: The asexual in sexusociety. Sexualities, 14, 444-461.

Storms, M. D. (1980). Theories of sexual orientation. Journal of Personality and Social Psychology, 38, 783–792.

Brain Disease and Creativity

31/05/2012 2 comments

Readers of this blog probably know I’m very interested in creativity. Recently, I came across a very interesting  review paper on artistry in brain disease by Schott.  Even though, many studies focus on the loss of various abilities as result of brain injury or disease, this review is focused on cases where brain disease resulted in enhanced artistic creativity in people with an interest in art or emergence of artistic creativity in art naive patients. Pictures created spontaneously by patient with brain disease sometimes present an excellent opportunity for studying that disease and revealing underlying mechanisms of cerebral dysfunction. It can also provide some useful information about creative processes in the healthy brain.

Dementia and stroke are very common. However, cases of patients who exhibit enhanced artistic output in these and other neurological disorders are rare or very rare. Miller et al. (2000) showed that enhanced artistry is probably more common but it is often under-reported, since new or preserved visual or musical ability was found in 17% of 69 patients with frontotemporal dementia.
In fact, frontotemporal dementia seems to be the brain disease more closely associated with increased creativity. Miller et al. (1996) were the first to report a patient with frontotemporal dementia that had developed new artistic creativity in the face of advancing dementia. A number of papers (Tanabe et al., 1996; Snowden et al., 1996), as well as Miller at al.’s seminal letter in the Lancet published in the same year brought more attention to the subject of preserved or increased artistic creativity in the presence of brain disease. Miller et al. (1996) described a 68-year-old male with a 12-year history of frontotemporal dementia,who, at the age of 56 years, started to paint having had no previous interest in art.

Patients with Alzheimer’s disease have also been reported to exhibit enhance artistic creativity. Professional painter, Danae Chambers, whose dementia started at around the age of 49 years (Fornazzari, 2005) is a striking example. Even though she was diagnosed with Alzheimer’s disease and her MRI scan revealed mild to moderate brain atrophy, there was no effect on her talent and creativity. However, it should be noted that typically during the progression of the disease stylistic changes leading to frank deterioration and eventual cessation of painting have been reported, especially in professional artists (see Crutch and Rossor, 2006).

In the case of autism there have been several cases of even very young autistics who could produce impressive works of art. A famous example is Stephen Wiltshire, who was able to draw astonishingly faithful architectural representations at the age of 7 years (Sacks, 1995).

According to Schott unexpected artistic creativity experienced by many patients has many features that suggest compulsive behaviour. Moreover, emergence of artistry after brain disease reflects innate rather than learned skills.

The brain correlates of emergent artistic creativity are rather obscure. It appears that dysfunction of the anterior temporal lobes is important if not crucial for the production of unexpectedly enhanced artistry, but the findings are often inconsistent. In some cases frontal lobe involvement is present too (Seeley et al., 2008).  Thus creative drive is thought to increase not only with abnormalities of temporal lobe function and ‘release’ of frontal lobe-mediated creativity, but also by involvement of the dopaminergic mesolimbic system (Flaherty, 2005)

One might wonder; is this emergence of artistic talent observed in patients with various brain diseases really creativity?

De Souza et al. (2010) then concluded: ‘The emergence of artistic talent in patients with fvFTLD is explained by the release of involuntary behaviors, rather than by the development of creative thinking’, and also recommended avoiding consideration of ‘pseudo-creative production, or the emergence of “artistic talent”, as a mastered mental production’.

The author, however, disagrees and concludes:

…the notion of pseudo-creation and identification of ‘artistic talent’ create more difficulties than enlightenment; rather, they emphatically confirm the importance of patients’ pictures. The evidence for creativity surely lies in the creation itself rather than in perfusion patterns or psychological tests.

ResearchBlogging.orgSchott, G. (2012). Pictures as a neurological tool: lessons from enhanced and emergent artistry in brain disease Brain, 135 (6), 1947-1963 DOI: 10.1093/brain/awr314

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?

Songs sound less sad when you’re older

22/06/2011 1 comment

Music is a powerful tool of expressing and inducing emotions. Lima and colleagues aimed at investigating whether and how emotion recognition in music changes as a function of ageing. Their study revealed that older participants showed decreased responses to music expressing negative emotions, while their perception of happy emotions remained stable.

Emotion plays an important role in music. Even infants have been found to be capable of identifying emotions in musical excerpts (Nawrot, 2003). However, recognition of emotion in music has received little attention so far. A new study by Lima and Castro published in Cognition and Emotion examined the effects of ageing on the recognition of emotions in music. Previous studies looking at emotion recognition in other modalities have revealed that increasing age is associated with a decline in the recognition of some emotions but not others (for more information see meta-analysis by Ruffman et al. (2008)). Laukka and Juslin (2007) examined the effects of ageing on emotion recognition in music comparing young adults (around 24) and older adults (older than 65). Their results identified that older adults had more difficulty recognizing fear and sadness in both music and speech prosody, whereas no differences were observed for anger, happiness and neutrality.

The sample used by Lima et al. was of 114 healthy adults (67 female). They were aged between 17 and 84 years, and were divided into three groups with 38 participants each: younger(mean age=21.8 years), middle-aged (mean age=44.5 years) and older adults (mean age=67.2 years). Each group listened to 56 short musical excerpts that expressed happiness, sadness, fear/threat and peacefulness. Each category was consisted of 14 stimuli.

The results revealed significant age-related changes associated with specific emotions. More specifically, the authors identified a progressive decline in responsiveness to sad and scary music. No difference was found in happy music. Differences between age groups were also observed in the pattern of misclassifications for sad and peaceful music. Younger participants perceived more sadness in peaceful music, older participants perceived more peacefulness. This could be due to the structural features of peaceful and sad songs, which are both characterised by slow tempo. Future studies could further investigate this. In addition to that, Lima et al. took into account the years of musical training that the participants had. This analysis revealed a positive association between music training and the categorisation of musical emotions.

One possible explanation for the main findings of this study suggests that the decline in the recognition of particular emotions might reflect the age-related neuropsychological decline in brain regions (such as the amygdala) involved in emotion processing. Previous studies have showed that distinct brain regions are involved in the perception of different emotions (Mitterschiffthaler et al., 2007). Another possible explanation is the age-related positivity bias (Mather & Carstensen, 2005; Carstensen & Mikels, 2005). Age-related positivity bias suggests that people get older, they experience fewer negative emotions.

Future studies could attempt to identify particular brain regions involved in emotion recognition at different ages. Furthermore, since the age-related positivity bias might not be universal (older Chinese participants looked away from happy facial expressions and not from negative ones, see Fung et al., 2008), it’d be very interesting to investigate the effects of ageing on emotion recognition in music in participants from different cultures.

ResearchBlogging.orgLima CF, & Castro SL (2011). Emotion recognition in music changes across the adult life span. Cognition & emotion, 25 (4), 585-98 PMID: 21547762

Carstensen, L., & Mikels, J. (2005). At the Intersection of Emotion and Cognition. Aging and the Positivity Effect Current Directions in Psychological Science, 14 (3), 117-121 DOI: 10.1111/j.0963-7214.2005.00348.x

Ruffman T, Henry JD, Livingstone V, & Phillips LH (2008). A meta-analytic review of emotion recognition and aging: implications for neuropsychological models of aging. Neuroscience and biobehavioral reviews, 32 (4), 863-81 PMID: 18276008

Laukka, P., & Juslin, P. (2007). Similar patterns of age-related differences in emotion recognition from speech and music Motivation and Emotion, 31 (3), 182-191 DOI: 10.1007/s11031-007-9063-z

Mather M, & Carstensen LL (2005). Aging and motivated cognition: the positivity effect in attention and memory. Trends in cognitive sciences, 9 (10), 496-502 PMID: 16154382

Mitterschiffthaler, M., Fu, C., Dalton, J., Andrew, C., & Williams, S. (2007). A functional MRI study of happy and sad affective states induced by classical music Human Brain Mapping, 28 (11), 1150-1162 DOI: 10.1002/hbm.20337

Nawrot, E. (2003). The Perception of Emotional Expression in Music: Evidence from Infants, Children and Adults Psychology of Music, 31 (1), 75-92 DOI: 10.1177/0305735603031001325

Fung HH, Lu AY, Goren D, Isaacowitz DM, Wadlinger HA, & Wilson HR (2008). Age-related positivity enhancement is not universal: older Chinese look away from positive stimuli. Psychology and aging, 23 (2), 440-6 PMID: 18573017

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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